@article{grundy_shah_nguyen_diederichsen_celik_desimone_mccloskey_balsara_2020, title={Impact of Frictional Interactions on Conductivity, Diffusion, and Transference Number in Ether- and Perfluoroether-Based Electrolytes}, volume={167}, ISSN={["1945-7111"]}, DOI={10.1149/1945-7111/abb34e}, abstractNote={There is growing interest in fluorinated electrolytes due to their high-voltage stability. We use full electrochemical characterization based on concentrated solution theory to investigate the underpinnings of conductivity and transference number in tetraglyme/LiTFSI mixtures (H4) and a fluorinated analog, C8-DMC, mixed with LiFSI (F4). Conductivity is significantly lower in F4 than in H4, and F4 exhibits negative cation transference numbers, while that of H4 is positive at most salt concentrations. By relating Stefan-Maxwell diffusion coefficients, which quantify ion-solvent and cation-anion frictional interactions, to conductivity and transference number, we determine that at high salt concentrations, the origin of differences in transference number is differences in anion-solvent interactions. We also define new Nernst-Einstein-like equations relating conductivity to Stefan-Maxwell diffusion coefficients. In H4 at moderate to high salt concentrations, we find that all molecular interactions must be included. However, we demonstrate another regime, in which conductivity is controlled by cation-anion interactions. The applicability of this assumption is quantified by a pre-factor, β + − , which is similar to the “ionicity” pre-factor that is often included in the Nernst-Einstein equation. In F4, β + − is unity at all salt concentrations, indicating that ionic conductivity is entirely controlled by the Stefan-Maxwell diffusion coefficient quantifying cation-anion frictional interactions.}, number={12}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Grundy, Lorena S. and Shah, Deep B. and Nguyen, Hien Q. and Diederichsen, Kyle M. and Celik, Hasan and DeSimone, Joseph M. and McCloskey, Bryan D. and Balsara, Nitash P.}, year={2020}, month={Jan} } @article{chintapalli_timachova_olson_mecham_desimone_balsara_2020, title={Lithium Salt Distribution and Thermodynamics in Electrolytes Based on Short Perfluoropolyether-block-Poly(ethylene oxide) Copolymers}, volume={53}, ISSN={["1520-5835"]}, DOI={10.1021/acs.macromol.9b01637}, abstractNote={Wide-angle X-ray scattering (WAXS) was used to study the distribution of salt in short-chain disordered block copolymer electrolytes with concentration fluctuations on the length scale of 1 nm. The...}, number={4}, journal={MACROMOLECULES}, author={Chintapalli, Mahati and Timachova, Ksenia and Olson, Kevin R. and Mecham, Sue J. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2020}, month={Feb}, pages={1142–1153} } @article{perry_tian_sengottuvel_harrison_gorentla_kapadia_cheng_luft_ting_desimone_et al._2020, title={Pulmonary Delivery of Nanoparticle-Bound Toll-like Receptor 9 Agonist for the Treatment of Metastatic Lung Cancer}, volume={14}, ISSN={["1936-086X"]}, DOI={10.1021/acsnano.0c02207}, abstractNote={CpG oligodeoxynucleotides (ODNs) are potent toll-like receptor (TLR) 9 agonists and have shown promise as anti-cancer agents in preclinical studies and clinical trials. Binding of CpG to TLR9 initiates a cascade of innate and adaptive immune responses, beginning with activation of dendritic cells, and resulting in a range of secondary effects that include the secretion of pro-inflammatory cytokines, activation of natural killer (NK) cells, and expansion of T cell populations. Recent literature suggests that local delivery of CpG in tumors results in superior antitumor effects as compared to systemic delivery. In this study, we utilized PRINT (particle replication in non-wetting templates) nanoparticles as a vehicle to deliver CpG into murine lungs through orotracheal instillations. In two orthotopic metastasis models of non-small cell lung cancer (NSCLC) - 344SQ (lung adenocarcinoma) and KAL-LN2E1 (lung squamous carcinoma), local delivery of PRINT-CpG into the lungs effectively promoted substantial tumor regression and also limited systemic toxicities associated with soluble CpG. Furthermore, cured mice were completely resistant to tumor re-challenge. Additionally, nano-delivery showed extended retention of CpG within the lungs as well as elevated anti-tumor cytokines. These results demonstrate that PRINT-CpG is a potent nanoplatform for local treatment of lung cancer that has collateral therapeutic effects on systemic disease, an encouraging toxicity profile, and may have the potential to treat lung metastasis of other cancer types.}, number={6}, journal={ACS NANO}, author={Perry, Jillian L. and Tian, Shaomin and Sengottuvel, Nisitha and Harrison, Emily B. and Gorentla, Balachandra K. and Kapadia, Chintan H. and Cheng, Ning and Luft, J. Christopher and Ting, Jenny P-Y and DeSimone, Joseph M. and et al.}, year={2020}, month={Jun}, pages={7200–7215} } @article{oh_aboian_yi_maslyn_loo_jiang_parkinson_wilson_moore_yee_et al._2019, title={3D Printed Absorber for Capturing Chemotherapy Drugs before They Spread through the Body}, volume={5}, ISSN={["2374-7951"]}, DOI={10.1021/acscentsci.8b00700}, abstractNote={Despite efforts to develop increasingly targeted and personalized cancer therapeutics, dosing of drugs in cancer chemotherapy is limited by systemic toxic side effects. We have designed, built, and deployed porous absorbers for capturing chemotherapy drugs from the bloodstream after these drugs have had their effect on a tumor, but before they are released into the body where they can cause hazardous side effects. The support structure of the absorbers was built using 3D printing technology. This structure was coated with a nanostructured block copolymer with outer blocks that anchor the polymer chains to the 3D printed support structure and a middle block that has an affinity for the drug. The middle block is polystyrenesulfonate which binds to doxorubicin, a widely used and effective chemotherapy drug with significant toxic side effects. The absorbers are designed for deployment during chemotherapy using minimally invasive image-guided endovascular surgical procedures. We show that the introduction of the absorbers into the blood of swine models enables the capture of 64 ± 6% of the administered drug (doxorubicin) without any immediate adverse effects. Problems related to blood clots, vein wall dissection, and other biocompatibility issues were not observed. This development represents a significant step forward in minimizing toxic side effects of chemotherapy.}, number={3}, journal={ACS CENTRAL SCIENCE}, author={Oh, Hee Jeung and Aboian, Mariam S. and Yi, Michael Y. J. and Maslyn, Jacqueline A. and Loo, Whitney S. and Jiang, Xi and Parkinson, Dilworth Y. and Wilson, Mark W. and Moore, Terilyn and Yee, Colin R. and et al.}, year={2019}, month={Mar}, pages={419–427} } @article{shah_nguyen_grundy_olson_mecham_desimone_balsara_2019, title={Difference between approximate and rigorously measured transference numbers in fluorinated electrolytes}, volume={21}, ISSN={["1463-9084"]}, DOI={10.1039/c9cp00216b}, abstractNote={Fluorinated electrolytes are highly non-ideal and Newman's concentrated solution theory must be used to fully characterize ion-transport.}, number={15}, journal={PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, author={Shah, Deep B. and Nguyen, Hien Q. and Grundy, Lorena S. and Olson, Kevin R. and Mecham, Sue J. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2019}, month={Apr}, pages={7857–7866} } @article{kapadia_tian_perry_luft_desimone_2019, title={Role of Linker Length and Antigen Density in Nanoparticle Peptide Vaccine}, volume={4}, ISSN={["2470-1343"]}, DOI={10.1021/acsomega.8b03391}, abstractNote={Multiple studies have been published emphasizing the significant role of nanoparticle (NP) carriers in antigenic peptide-based subunit vaccines for the induction of potent humoral and cellular responses. Various design parameters of nanoparticle subunit vaccines such as linker chemistry, the proximity of antigenic peptide to NPs, and the density of antigenic peptides on the surface of NPs play an important role in antigen presentation to dendritic cells (DCs) and in subsequent induction of CD8+ T cell response. In this current study, we evaluated the role of peptide antigen proximity and density on DC uptake, antigen cross-presentation, in vitro T cell proliferation, and in vivo induction of CD8+ T cells. To evaluate the role of antigen proximity, CSIINFEKL peptides were systematically conjugated to poly(ethylene glycol) (PEG) hydrogels through N-hydroxysuccinimide–PEG–maleimide linkers of varying molecular weights: 2k, 5k, and 10k. We observed that the peptides conjugated to NPs via the 2k and 5k PEG linkers resulted in higher uptake in bone marrow-derived DCs (BMDCs) and increased p-MHC-I formation on the surface of bone marrow-derived DCs (BMDCs) as compared to the 10k PEG linker formulation. However, no significant differences in vitro T cell proliferation and induction of in vivo CD8+ T cells were found among linker lengths. To study the effect of antigen density, CSIINFEKL peptides were conjugated to PEG hydrogels via 5k PEG linkers at various densities. We found that high antigen density NPs presented the highest p-MHC-I on the surface of BMDCs and induced higher proliferation of T cells, whereas NPs with low peptide density resulted in higher DC cell uptake and elevated frequency of IFN-γ producing CD8+ T cells in mice as compared to the medium- and high-density formulations. Altogether, findings for these experiments highlighted the importance of linker length and peptide antigen density on DC cell uptake, antigen presentation, and induction of in vivo CD8+ T cell response.}, number={3}, journal={ACS OMEGA}, author={Kapadia, Chintan H. and Tian, Shaomin and Perry, Jillian L. and Luft, J. Christopher and Desimone, Joseph M.}, year={2019}, month={Mar}, pages={5547–5555} } @article{bloomquist_mecham_paradzinsky_janusziewicz_warner_luft_mecham_wang_desimone_2018, title={Controlling release from 3D printed medical devices using CLIP and drug-loaded liquid resins}, volume={278}, ISSN={["1873-4995"]}, DOI={10.1016/j.jconrel.2018.03.026}, abstractNote={Mass customization along with the ability to generate designs using medical imaging data makes 3D printing an attractive method for the fabrication of patient-tailored drug and medical devices. Herein we describe the application of Continuous Liquid Interface Production (CLIP) as a method to fabricate biocompatible and drug-loaded devices with controlled release properties, using liquid resins containing active pharmaceutical ingredients (API). In this work, we characterize how the release kinetics of a model small molecule, rhodamine B-base (RhB), are affected by device geometry, network crosslink density, and the polymer composition of polycaprolactone- and poly (ethylene glycol)-based networks. To demonstrate the applicability of using API-loaded liquid resins with CLIP, the UV stability was evaluated for a panel of clinically-relevant small molecule drugs. Finally, select formulations were tested for biocompatibility, degradation and encapsulation of docetaxel (DTXL) and dexamethasone-acetate (DexAc). Formulations were shown to be biocompatible over the course of 175 days of in vitro degradation and the clinically-relevant drugs could be encapsulated and released in a controlled fashion. This study reveals the potential of the CLIP manufacturing platform to serve as a method for the fabrication of patient-specific medical and drug-delivery devices for personalized medicine.}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Bloomquist, Cameron J. and Mecham, Michael B. and Paradzinsky, Mark D. and Janusziewicz, Rima and Warner, Samuel B. and Luft, J. Christopher and Mecham, Sue J. and Wang, Andrew Z. and DeSimone, Joseph M.}, year={2018}, month={May}, pages={9–23} } @article{wilson_luft_desimone_2018, title={Formulation of High-Performance Dry Powder Aerosols for Pulmonary Protein Delivery}, volume={35}, ISSN={["1573-904X"]}, DOI={10.1007/s11095-018-2452-z}, abstractNote={{"Label"=>"PURPOSE", "NlmCategory"=>"OBJECTIVE"} Pulmonary delivery of biologics is of great interest, as it can be used for the local treatment of respiratory diseases or as a route to systemic drug delivery. To reach the full potential of inhaled biologics, a formulation platform capable of producing high performance aerosols without altering protein native structure is required. {"Label"=>"METHODS", "NlmCategory"=>"METHODS"} A formulation strategy using Particle Replication in Non-wetting Templates (PRINT) was developed to produce protein dry powders with precisely engineered particle morphology. Stability of the incorporated proteins was characterized and the aerosol properties of the protein dry powders was evaluated in vitro with an Andersen Cascade Impactor (ACI). {"Label"=>"RESULTS", "NlmCategory"=>"RESULTS"} Model proteins bovine serum albumin (BSA) and lysozyme were micromolded into 1 μm cylinders composed of more than 80% protein, by mass. Extensive characterization of the incorporated proteins found no evidence of alteration of native structures. The BSA formulation produced a mass median aerodynamic diameter (MMAD) of 1.77 μm ± 0.06 and a geometric standard deviation (GSD) of 1.51 ± 0.06 while the lysozyme formulation had an MMAD of 1.83 μm ± 0.12 and a GSD of 1.44 ± 0.03. {"Label"=>"CONCLUSION", "NlmCategory"=>"CONCLUSIONS"} Protein dry powders manufactured with PRINT could enable high-performance delivery of protein therapeutics to the lungs.}, number={10}, journal={PHARMACEUTICAL RESEARCH}, author={Wilson, Erin M. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2018}, month={Oct} } @article{byrne_jajja_adrian t. o'neill_schorzman_keeler_luft_zamboni_desimone_yeh_2018, title={Impact of formulation on the iontophoretic delivery of the FOLFIRINOX regimen for the treatment of pancreatic cancer}, volume={81}, ISSN={["1432-0843"]}, DOI={10.1007/s00280-018-3570-3}, abstractNote={Effective treatment of patients with locally advanced pancreatic cancer is a significant unmet clinical need. One major hurdle that exists is inadequate drug delivery due to the desmoplastic stroma and poor vascularization that is characteristic of pancreatic cancer. The local iontophoretic delivery of chemotherapies provides a novel way of improving treatment. With the growing practice of highly toxic combination therapies in the treatment of pancreatic cancer, the use of iontophoresis for local delivery can potentiate the anti-cancer effects of these therapies while sparing unwanted toxicity. The objective of this study was to investigate the impact of formulation on the electro-transport of the FOLFIRINOX regimen for the development of a new treatment for pancreatic cancer. Three formulations of the FOLFIRINOX regimen (5-fluorouracil, leucovorin, irinotecan, and oxaliplatin) were generated at a fixed pH of 6.0 and were referred to as formulation A (single drug solution with all four drugs combined), formulation B (two drug solutions with two drugs per solution), and formulation C (four individual drug solutions). Anodic iontophoresis of the three different formulations was evaluated in orthotopic patient-derived xenografts of pancreatic cancer. Iontophoretic transport of the FOLFIRINOX drugs was characterized according to organ exposure after a single device treatment in vivo. We report that the co-iontophoresis of two drug solutions, leucovorin + oxaliplatin and 5-fluorouracil + irinotecan, resulted in the highest levels of cytotoxic drugs in the tumor compared to drugs delivered individually or combined into one solution. There was no significant difference in plasma, pancreas, kidney, and liver exposure to the cytotoxic drugs delivered by the three different formulations. In addition, we found that reducing the duration of iontophoretic treatment from 10 to 5 min per solution resulted in a significant decrease in drug concentrations. Underlying the difference in drug transport of the formulations was electrolyte concentrations, which includes both active and inactive components. Electrolyte concentrations can hinder or improve drug electro-transport. Overall, balancing electrolyte concentration is needed for optimal electro-transport.}, number={6}, journal={CANCER CHEMOTHERAPY AND PHARMACOLOGY}, author={Byrne, James D. and Jajja, Mohammad R. N. and Adrian T. O'Neill and Schorzman, Allison N. and Keeler, Amanda W. and Luft, J. Christopher and Zamboni, William C. and DeSimone, Joseph M. and Yeh, Jen Jen}, year={2018}, month={Jun}, pages={991–998} } @article{coffman_metz_brackbill_paul_miley_desimone_luft_silva_tian_2018, title={Optimization of Surface Display of DENV2 E Protein on a Nanoparticle to Induce Virus Specific Neutralizing Antibody Responses}, volume={29}, ISSN={["1520-4812"]}, DOI={10.1021/acs.bioconjchem.8b00090}, abstractNote={The dengue virus (DENV) causes over 350 million infections, resulting in ∼25,000 deaths per year globally. An effective dengue vaccine requires generation of strong and balanced neutralizing antibodies against all four antigenically distinct serotypes of DENV. The leading live-attenuated tetravalent dengue virus vaccine platform has shown partial efficacy, with an unbalanced response across the four serotypes in clinical trials. DENV subunit vaccine platforms are being developed because they provide a strong safety profile and are expected to avoid the unbalanced immunization issues associated with live multivalent vaccines. Subunit vaccines often lack immunogenicity, requiring either a particulate or adjuvanted formulation. Particulate formulations adsorbing monomeric DENV-E antigen to the particle surface incite a strong immune response, but have no control of antigen presentation. Highly neutralizing epitopes are displayed by DENV-E quaternary structures. To control the display of DENV-E and produce quaternary structures, particulate formulations that covalently attach DENV-E to the particle surface are needed. Here we develop a surface attached DENV2-E particulate formulation, as well as analysis tools, using PEG hydrogel nanoparticles created with particle replication in nonwetting templates (PRINT) technology. We found that adding Tween-20 to the conjugation buffer controls DENV-E adsorption to the particle surface during conjugation, improving both protein stability and epitope display. Immunizations with the anionic but not the cationic DENV2-E conjugated particles were able to produce DENV-specific and virus neutralizing antibody in mice. This work optimized the display of DENV-E conjugated to the surface of a nanoparticle through EDC/NHS chemistry, establishing a platform that can be expanded upon in future work to fully control the display of DENV-E.}, number={5}, journal={BIOCONJUGATE CHEMISTRY}, author={Coffman, Jason E. and Metz, Stefan W. and Brackbill, Alex and Paul, Molly and Miley, Michael J. and DeSimone, Joseph and Luft, J. Christopher and Silva, Aravinda and Tian, Shaomin}, year={2018}, month={May}, pages={1544–1552} } @article{caudill_perry_tian_luft_desimone_2018, title={Spatially controlled coating of continuous liquid interface production microneedles for transdermal protein delivery}, volume={284}, ISSN={["1873-4995"]}, DOI={10.1016/j.jconrel.2018.05.042}, abstractNote={Microneedle patches, arrays of micron-scale projections that penetrate skin in a minimally invasive manner, are a promising tool for transdermally delivering therapeutic proteins. However, current microneedle fabrication techniques are limited in their ability to fabricate microneedles rapidly and with a high degree of control over microneedle design parameters. We have previously demonstrated the ability to fabricate microneedle patches with a range of compositions and geometries using the novel additive manufacturing technique Continuous Liquid Interface Production (CLIP). Here, we establish a method for dip coating CLIP microneedles with protein cargo in a spatially controlled manner. Microneedle coating mask devices were fabricated with CLIP and utilized to coat polyethylene glycol-based CLIP microneedles with model proteins bovine serum albumin, ovalbumin, and lysozyme. The design of the coating mask device was used to control spatial deposition and loading of coated protein cargo on the microneedles. CLIP microneedles rapidly released coated protein cargo both in solution and upon insertion into porcine skin. The model enzyme lysozyme was shown to retain its activity throughout the CLIP microneedle coating process, and permeation of bovine serum albumin across full thickness porcine skin was observed after application with coated CLIP microneedles. Protein-coated CLIP microneedles were applied to live mice and showed sustained retention of protein cargo in the skin over 72 h. These results demonstrate the utility of a versatile coating platform for preparation of precisely coated microneedles for transdermal therapeutic delivery.}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Caudill, Cassie L. and Perry, Jillian L. and Tian, Shaomin and Luft, J. Christopher and DeSimone, Joseph M.}, year={2018}, month={Aug}, pages={122–132} } @misc{byrne_yeh_desimone_2018, title={Use of iontophoresis for the treatment of cancer}, volume={284}, ISSN={["1873-4995"]}, DOI={10.1016/j.jconrel.2018.06.020}, abstractNote={Despite major advancements in cancer treatments, there are still many limitations to therapy including off-target effects, drug resistance, and control of cancer-related symptoms. There are opportunities for local drug delivery devices to intervene at various stages of cancer to provide curative and palliative benefit. Iontophoretic devices that deliver drugs locally to a region of interest have been adapted for the treatment of cancer. These devices have shown promise in pre-clinical and clinical studies for retinoblastoma, skin, bladder, and pancreatic cancers. Herein, we review iontophoretic devices used in the management of cancer.}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Byrne, James D. and Yeh, Jen Jen and DeSimone, Joseph M.}, year={2018}, month={Aug}, pages={144–151} } @article{min_roche_tian_eblan_mckinnon_caster_chai_herring_zhang_zhang_et al._2017, title={Antigen-capturing nanoparticles improve the abscopal effect and cancer immunotherapy}, volume={12}, ISSN={["1748-3395"]}, DOI={10.1038/nnano.2017.113}, abstractNote={Immunotherapy holds tremendous promise for improving cancer treatment. To administer radiotherapy with immunotherapy has been shown to improve immune responses and can elicit the 'abscopal effect'. Unfortunately, response rates for this strategy remain low. Herein we report an improved cancer immunotherapy approach that utilizes antigen-capturing nanoparticles (AC-NPs). We engineered several AC-NP formulations and demonstrated that the set of protein antigens captured by each AC-NP formulation is dependent on the NP surface properties. We showed that AC-NPs deliver tumour-specific proteins to antigen-presenting cells (APCs) and significantly improve the efficacy of αPD-1 (anti-programmed cell death 1) treatment using the B16F10 melanoma model, generating up to a 20% cure rate compared with 0% without AC-NPs. Mechanistic studies revealed that AC-NPs induced an expansion of CD8}, number={9}, journal={NATURE NANOTECHNOLOGY}, author={Min, Yuanzeng and Roche, Kyle C. and Tian, Shaomin and Eblan, Michael J. and McKinnon, Karen P. and Caster, Joseph M. and Chai, Shengjie and Herring, Laura E. and Zhang, Longzhen and Zhang, Tian and et al.}, year={2017}, month={Sep}, pages={877-+} } @article{devaux_villaluenga_bhatt_shah_chen_thelen_desimone_balsara_2017, title={Crosslinked perfluoropolyether solid electrolytes for lithium ion transport}, volume={310}, ISSN={["1872-7689"]}, DOI={10.1016/j.ssi.2017.08.007}, abstractNote={Perfluoropolyethers (PFPE) are commercially available non-flammable short chain polymeric liquids. End-functionalized PFPE chains solvate lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt and these mixtures can be used as electrolytes for lithium (Li) batteries. Here we synthesize and characterize a new class of solid PFPE electrolytes. The electrolytes are made by either thermal or UV crosslinking PFPE chains with urethane methacrylate end-groups. For the synthesis of thermally crosslinked electrolytes, polyhedral oligomeric silsesquioxane (POSS) with organic acrylopropyl groups was used as crosslinker agent, while for UV cured electrolytes a photoinitiatior was used. We present thermal, morphological, and electrical data of the solid electrolytes. We compare these properties with those of the two parent liquids (PFPE with urethane methacrylate end-groups and POSS with acrylopropyl groups) mixed with LiTFSI. The solubility limit of LiTFSI in the PFPE-based solids is higher than that in the liquids. The conductivity data are analyzed using the Vogel–Tamman–Fulcher equation. The concentration of effective charge carriers is a strong function of the nature of the solvent (solid versus liquid) whereas the activation energy is neither a strong function of the nature of the solvent nor salt concentration.}, journal={SOLID STATE IONICS}, author={Devaux, Didier and Villaluenga, Irune and Bhatt, Mahesh and Shah, Deep and Chen, X. Chelsea and Thelen, Jacob L. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2017}, month={Nov}, pages={71–80} } @article{shah_olson_karny_mecham_desimone_balsara_2017, title={Effect of Anion Size on Conductivity and Transference Number of Perfluoroether Electrolytes with Lithium Salts}, volume={164}, ISSN={["1945-7111"]}, DOI={10.1149/2.0301714jes}, abstractNote={Author(s): Shah, DB; Olson, KR; Karny, A; Mecham, SJ; DeSimone, JM; Balsara, NP | Abstract: Mixtures of perfluoropolyethers (PFPE) and lithium salts with fluorinated anions are a new class of electrolytes for lithium batteries. Unlike conventional electrolytes wherein electron-donating oxygen groups interact primarily with the lithium cations, the properties of PFPE-based electrolytes appear to be dependent on interactions between the fluorinated anions and the fluorinated backbones. We study these interactions by examining a family of lithium salts wherein the size of the fluorinated anion is systematically increased: lithium bis(fluorosulfonyl)imide (LiFSI), bis(trifluoromethanesulfonyl)imide (LiTFSI) salts and lithium bis(pentafluoroethanesulfonyl)imide (LiBETI). Two short chain perfluoroethers (PFE), one with three repeat units, C6-DMC, and another with four repeat units, C8-DMC were studied; both systems have dimethyl carbonate end groups.We find that LiFSI provides the highest conductivity in both C6-DMC and C8-DMC. These systems also present the lowest interfacial resistance against lithium metal electrodes. The steady-state transference number (t+ss) was above 0.6 for all of the electrolytes and was an increasing function of anion size. The product of conductivity and the steady-state transference number, a convenient measure of the efficacy of the electrolytes for lithium battery applications, exhibited a maximum at about 20 wt% salt in all electrolytes. Amongst the systems studied, LiFSI/PFE mixtures were the most efficacious electrolytes.}, number={14}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Shah, Deep B. and Olson, Kevin R. and Karny, Adar and Mecham, Sue J. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2017}, pages={A3511–A3517} } @article{chintapalli_timachova_olson_banaszak_thelen_mecham_desimone_balsara_2017, title={Incipient microphase separation in short chain perfluoropolyether-block-poly(ethylene oxide) copolymers}, volume={13}, ISSN={["1744-6848"]}, DOI={10.1039/c7sm00738h}, abstractNote={Incipient microphase separation is observed by wide angle X-ray scattering (WAXS) in short chain multiblock copolymers consisting of perfluoropolyether (PFPE) and poly(ethylene oxide) (PEO) segments. Two PFPE-PEO block copolymers were studied; one with dihydroxyl end groups and one with dimethyl carbonate end groups. Despite having a low degree of polymerization (N ∼ 10), these materials exhibited significant scattering intensity, due to disordered concentration fluctuations between their PFPE-rich and PEO-rich domains. The disordered scattering intensity was fit to a model based on a multicomponent random phase approximation to determine the value of the interaction parameter, χ, and the radius of gyration, Rg. Over the temperature range 30-90 °C, the values of χ were determined to be very large (∼2-2.5), indicating a high degree of immiscibility between the PFPE and PEO blocks. In PFPE-PEO, due to the large electron density contrast between the fluorinated and non-fluorinated block and the high value of χ, disordered scattering was detected at intermediate scattering angles, (q ∼ 2 nm-1) for relatively small polymer chains. Our ability to detect concentration fluctuations was enabled by both a relatively large value of χ and significant scattering contrast.}, number={22}, journal={SOFT MATTER}, author={Chintapalli, Mahati and Timachova, Ksenia and Olson, Kevin R. and Banaszak, Michal and Thelen, Jacob L. and Mecham, Sue J. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2017}, month={Jun}, pages={4047–4056} } @article{timachova_chintapalli_olson_mecham_desimone_balsara_2017, title={Mechanism of ion transport in perfluoropolyether electrolytes with a lithium salt}, volume={13}, ISSN={["1744-6848"]}, DOI={10.1039/c7sm00794a}, abstractNote={Perfluoropolyethers (PFPEs) are polymer electrolytes with fluorinated carbon backbones that have high flash points and have been shown to exhibit moderate conductivities and high cation transference numbers when mixed with lithium salts.}, number={32}, journal={SOFT MATTER}, author={Timachova, Ksenia and Chintapalli, Mahati and Olson, Kevin R. and Mecham, Sue J. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2017}, month={Aug}, pages={5389–5396} } @article{perry_reuter_luft_pecot_zamboni_desimone_2017, title={Mediating Passive Tumor Accumulation through Particle Size, Tumor Type, and Location}, volume={17}, ISSN={["1530-6992"]}, DOI={10.1021/acs.nanolett.7b00021}, abstractNote={As the enhanced permeation and retention (EPR) effect continues to be a controversial topic in nanomedicine, we sought to examine EPR as a function of nanoparticle size, tumor model, and tumor location, while also evaluating tumors for EPR mediating factors such as microvessel density, vascular permeability, lymphatics, stromal content, and tumor-associated immune cells. Tumor accumulation was evaluated for 55 × 60, 80 × 180, and 80 × 320 nm PRINT particles in four subcutaneous flank tumor models (SKOV3 human ovarian, 344SQ murine nonsmall cell lung, A549 human nonsmall cell lung, and A431 human epidermoid cancer). Each tumor model revealed specific particle accumulation trends with evident particle size dependence. Immuno-histochemistry staining revealed differences in tumor microvessel densities that correlated with overall tumor accumulation. Immunofluorescence images displayed size-mediated tumor penetration with signal from the larger particles concentrated close to the blood vessels, while signal from the smaller particle was observed throughout the tissue. Differences were also observed for the 55 × 60 nm particle tumor penetration across flank tumor models as a function of stromal content. The 55 × 60 nm particles were further evaluated in three orthotopic, metastatic tumor models (344SQ, A549, and SKOV3), revealing preferential accumulation in primary tumors and metastases over healthy tissue. Moreover, we observed higher tumor accumulation in the orthotopic lung cancer models than in the flank lung cancer models, whereas tumor accumulation was constant for both orthotopic and flank ovarian cancer models, further demonstrating the variability in the EPR effect as a function of tumor model and location.}, number={5}, journal={NANO LETTERS}, author={Perry, Jillian L. and Reuter, Kevin G. and Luft, J. Christopher and Pecot, Chad V. and Zamboni, William and DeSimone, Joseph M.}, year={2017}, month={May}, pages={2879–2886} } @article{desimone_2016, title={Co-opting Moore's law: Therapeutics, vaccines and interfacially active particles manufactured via PRINT®}, volume={240}, ISSN={0168-3659}, url={http://dx.doi.org/10.1016/j.jconrel.2016.07.019}, DOI={10.1016/j.jconrel.2016.07.019}, abstractNote={Nanoparticle properties such as size, shape, deformability, and surface chemistry all play a role in nanomedicine drug delivery. While many studies address the behavior of particle systems in a biological setting, revealing how these properties work together presents unique challenges on the nanoscale. Particle replication in non-wetting templates (PRINT®) is one molding technique that allows for fabrication of "calibration quality" micro and nanoparticles with independent control over their physical parameters. As the only technology in the world capable of independently optimizing and robustly manufacturing GMP compliant precision particles of virtually any size, shape, and composition, the PRINT technology has the capability to engineer the future of healthcare.}, journal={Journal of Controlled Release}, publisher={Elsevier BV}, author={DeSimone, Joseph M.}, year={2016}, month={Oct}, pages={541–543} } @article{devaux_chang_villaluenga_chen_chintapalli_desimone_balsara_2016, title={Conductivity of carbonate- and perfluoropolyether-based electrolytes in porous separators}, volume={323}, ISSN={["1873-2755"]}, DOI={10.1016/j.jpowsour.2016.05.039}, abstractNote={In lithium batteries, a porous separator filled with an electrolyte is placed in between the electrodes. Properties of the separator such as porosity and wettability strongly influence the conductivity of the electrolyte-separator composite. This study focuses on three commercial separators: a single layer polypropylene (Celgard 2500), a trilayer polypropylene-polyethylene-polypropylene (PP-PE-PP), and a porous polytetrafluoroethylene (PTFE). Electron microscopy was used to characterize the pore structure, and these experiments reveal large differences in pore morphology. The separators were soaked in both carbonate- and perfluoropolyether-based electrolytes. The conductivity of the neat electrolytes (σ0) varied from 6.46 × 10−6 to 1.76 × 10−2 S cm−1. The porosity and wettability of the separator affect the electrolyte uptake that in turn affect the conductivity of electrolyte-separator composites. The conductivity of the electrolyte-separator composites (σ) was found to follow a master equation, σ = 0.51·σ0·ϕc3.2±0.2, where ϕc is the volume fraction of the electrolyte in each separator.}, journal={JOURNAL OF POWER SOURCES}, author={Devaux, Didier and Chang, Yu H. and Villaluenga, Irune and Chen, X. Chelsea and Chintapalli, Mahati and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2016}, month={Aug}, pages={158–165} } @article{bowerman_byrne_chu_schorzman_keeler_sherwood_perry_luft_darr_deal_et al._2017, title={Docetaxel-Loaded PLGA Nanoparticles Improve Efficacy in Taxane-Resistant Triple-Negative Breast Cancer}, volume={17}, ISSN={["1530-6992"]}, DOI={10.1021/acs.nanolett.6b03971}, abstractNote={Novel treatment strategies, including nanomedicine, are needed for improving management of triple-negative breast cancer. Patients with triple-negative breast cancer, when considered as a group, have a worse outcome after chemotherapy than patients with breast cancers of other subtypes, a finding that reflects the intrinsically adverse prognosis associated with the disease. The aim of this study was to improve the efficacy of docetaxel by incorporation into a novel nanoparticle platform for the treatment of taxane-resistant triple-negative breast cancer. Rod-shaped nanoparticles encapsulating docetaxel were fabricated using an imprint lithography based technique referred to as Particle Replication in Nonwetting Templates (PRINT). These rod-shaped PLGA-docetaxel nanoparticles were tested in the C3(1)-T-antigen (C3Tag) genetically engineered mouse model (GEMM) of breast cancer that represents the basal-like subtype of triple-negative breast cancer and is resistant to therapeutics from the taxane family. This GEMM recapitulates the genetics of the human disease and is reflective of patient outcome and, therefore, better represents the clinical impact of new therapeutics. Pharmacokinetic analysis showed that delivery of these PLGA-docetaxel nanoparticles increased docetaxel circulation time and provided similar docetaxel exposure to tumor compared to the clinical formulation of docetaxel, Taxotere. These PLGA-docetaxel nanoparticles improved tumor growth inhibition and significantly increased median survival time. This study demonstrates the potential of nanotechnology to improve the therapeutic index of chemotherapies and rescue therapeutic efficacy to treat nonresponsive cancers.}, number={1}, journal={NANO LETTERS}, author={Bowerman, Charles J. and Byrne, James D. and Chu, Kevin S. and Schorzman, Allison N. and Keeler, Amanda W. and Sherwood, Candice A. and Perry, Jillian L. and Luft, James C. and Darr, David B. and Deal, Allison M. and et al.}, year={2017}, month={Jan}, pages={242–248} } @article{sambade_deal_schorzman_luft_bowerman_chu_karginova_swearingen_zamboni_desimone_et al._2016, title={Efficacy and pharmacokinetics of a modified acid-labile docetaxel-PRINT® nanoparticle formulation against non-small-cell lung cancer brain metastases}, volume={11}, ISSN={1743-5889 1748-6963}, url={http://dx.doi.org/10.2217/nnm-2016-0147}, DOI={10.2217/nnm-2016-0147}, abstractNote={ Aim: Particle Replication in Nonwetting Templates (PRINT®) PLGA nanoparticles of docetaxel and acid-labile C2-dimethyl-Si-Docetaxel were evaluated with small molecule docetaxel as treatments for non-small-cell lung cancer brain metastases. Materials & methods: Pharmacokinetics, survival, tumor growth and mice weight change were efficacy measures against intracranial A549 tumors in nude mice. Treatments were administered by intravenous injection. Results: Intracranial tumor concentrations of PRINT-docetaxel and PRINT-C2-docetaxel were 13- and sevenfold greater, respectively, than SM-docetaxel. C2-docetaxel conversion to docetaxel was threefold higher in intracranial tumor as compared with nontumor tissues. PRINT-C2-docetaxel increased median survival by 35% with less toxicity as compared with other treatments. Conclusion: The decreased toxicity of the PRINT-C2-docetaxel improved treatment efficacy against non-small-cell lung cancer brain metastasis. }, number={15}, journal={Nanomedicine}, publisher={Future Medicine Ltd}, author={Sambade, Maria and Deal, Allison and Schorzman, Allison and Luft, J Christopher and Bowerman, Charles and Chu, Kevin and Karginova, Olga and Swearingen, Amanda Van and Zamboni, William and DeSimone, Joseph and et al.}, year={2016}, month={Aug}, pages={1947–1955} } @article{byrne_jajja_schorzman_keeler_luft_zamboni_desimone_yeh_2016, title={Iontophoretic device delivery for the localized treatment of pancreatic ductal adenocarcinoma}, volume={113}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1600421113}, abstractNote={Significance Drug delivery to pancreatic tumors is impaired by a unique desmoplastic response and poor tumor vascularization. A drug delivery device capable of overcoming these barriers could provide substantial benefit for patients with pancreatic cancer. In this study, we show that local iontophoretic delivery of folinic acid (leucovorin), fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) resulted in better tumor response and tolerability compared with i.v. FOLFIRINOX. Given the low systemic exposure of FOLFIRINOX using iontophoretic delivery, it may be possible to use in combination with systemic delivery to treat micrometastatic disease. Local iontophoretic delivery of cytotoxic agents should be considered as a neoadjuvant approach to improve resection rates and outcome in patients with localized and locally advanced pancreatic cancer.}, number={8}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Byrne, James D. and Jajja, Mohammad R. N. and Schorzman, Allison N. and Keeler, Amanda W. and Luft, J. Christopher and Zamboni, William C. and DeSimone, Joseph M. and Yeh, Jen Jen}, year={2016}, month={Feb}, pages={2200–2205} } @article{janusziewicz_tumbleston_quintanilla_mecham_desimone_2016, title={Layerless fabrication with continuous liquid interface production}, volume={113}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1605271113}, abstractNote={Despite the increasing popularity of 3D printing, also known as additive manufacturing (AM), the technique has not developed beyond the realm of rapid prototyping. This confinement of the field can be attributed to the inherent flaws of layer-by-layer printing and, in particular, anisotropic mechanical properties that depend on print direction, visible by the staircasing surface finish effect. Continuous liquid interface production (CLIP) is an alternative approach to AM that capitalizes on the fundamental principle of oxygen-inhibited photopolymerization to generate a continual liquid interface of uncured resin between the growing part and the exposure window. This interface eliminates the necessity of an iterative layer-by-layer process, allowing for continuous production. Herein we report the advantages of continuous production, specifically the fabrication of layerless parts. These advantages enable the fabrication of large overhangs without the use of supports, reduction of the staircasing effect without compromising fabrication time, and isotropic mechanical properties. Combined, these advantages result in multiple indicators of layerless and monolithic fabrication using CLIP technology.}, number={42}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Janusziewicz, Rima and Tumbleston, John R. and Quintanilla, Adam L. and Mecham, Sue J. and DeSimone, Joseph M.}, year={2016}, month={Oct}, pages={11703–11708} } @article{olson_wong_chintapalli_timachova_janusziewicz_daniel_mecham_sheiko_balsara_desimone_2016, title={Liquid perfluoropolyether electrolytes with enhanced ionic conductivity for lithium battery applications}, volume={100}, ISSN={["1873-2291"]}, DOI={10.1016/j.polymer.2016.08.020}, abstractNote={We prepared nonflammable liquid polymer electrolytes for lithium-ion batteries by mixing ethoxylated perfluoropolyethers (PFPEs) with LiN(SO2CF3)2 salt. Interestingly, we identified the presence of chain coupling in the PFPE polymers and their functionalized derivatives, resulting in a mixture of PFPEs with varying molecular weights. The distribution of molecular weights, along with PFPE's multiple functionalities, allows systematic manipulation of structure to enhance electrochemical and physical properties. Furthermore, the electrolytes exhibited a wide thermal stability window (5% degradation temperature >180 °C). Despite substantial increases in viscosity upon loading the PFPEs with lithium salt, the conductivity (σ ≈ 5 × 10−5 S cm−1 at 28 °C) of the novel electrolytes was about an order of magnitude higher than that of our previously reported PFPE electrolytes. Ethoxylated derivatives of PFPE electrolytes exhibit elevated conductivity compared to non-ethoxylated derivatives, demonstrating our capability to enhance the conductive properties of the PFPE platform by attaching various functional groups to the polymer backbone.}, journal={POLYMER}, author={Olson, Kevin R. and Wong, Dominica H. C. and Chintapalli, Mahati and Timachova, Ksenia and Janusziewicz, Rima and Daniel, William F. M. and Mecham, Sue and Sheiko, Sergei and Balsara, Nitash P. and DeSimone, Joseph M.}, year={2016}, month={Sep}, pages={126–133} } @article{fromen_rahhal_robbins_kai_shen_luft_desimone_2016, title={Nanoparticle surface charge impacts distribution, uptake and lymph node trafficking by pulmonary antigen-presenting cells}, volume={12}, ISSN={["1549-9642"]}, DOI={10.1016/j.nano.2015.11.002}, abstractNote={Engineered nanoparticles have the potential to expand the breadth of pulmonary therapeutics, especially as respiratory vaccines. Notably, cationic nanoparticles have been demonstrated to produce superior local immune responses following pulmonary delivery; however, the cellular mechanisms of this increased response remain unknown. To this end, we investigated the cellular response of lung APCs following pulmonary instillation of anionic and cationic charged nanoparticles. While nanoparticles of both surface charges were capable of trafficking to the draining lymph node and were readily internalized by alveolar macrophages, both CD11b and CD103 lung dendritic cell (DC) subtypes preferentially associated with cationic nanoparticles. Instillation of cationic nanoparticles resulted in the upregulation of Ccl2 and Cxc10, which likely contributes to the recruitment of CD11b DCs to the lung. In total, these cellular mechanisms explain the increased efficacy of cationic formulations as a pulmonary vaccine carrier and provide critical benchmarks in the design of pulmonary vaccine nanoparticles. Advance in nanotechnology has allowed the production of precise nanoparticles as vaccines. In this regard, pulmonary delivery has the most potential. In this article, the authors investigated the interaction of nanoparticles with various types of lung antigen presenting cells in an attempt to understand the cellular mechanisms. The findings would further help the future design of much improved vaccines for clinical use.}, number={3}, journal={NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE}, author={Fromen, Catherine A. and Rahhal, Tojan B. and Robbins, Gregory R. and Kai, Marc P. and Shen, Tammy W. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2016}, month={Apr}, pages={677–687} } @article{rogers_desimone_2016, title={Novel materials}, volume={113}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.1614927113}, DOI={10.1073/pnas.1614927113}, abstractNote={Materials have central roles in all fields of engineering; they define, through structures and devices, our interfaces to the physical and the virtual world. The emergence of new materials catalyzes transformative advances in civilizations, to an extent that eras of human development are often defined by the prevailing materials used in engineered systems, from the Stone, Bronze, and Iron Ages to the present times, aptly referred to as the Silicon or the Polymer Age. From an academic standpoint, the fundamental phenomena that define complex relationships between chemical compositions, structures, and properties in advanced materials serve as the basis for some of the most intellectually stimulating and dynamic areas of research in the physical sciences. This work has additional appeal because it is intrinsically interdisciplinary and combines essential aspects of traditional fields of study in physics, chemistry, and even biology, to an increasing extent, together with engineering processes and control strategies. Progress in materials science and in the engineering application of new materials is essential to the pursuit of solutions to societal grand challenges. Examples span those related to the development of sustainable sources of energy, from high-power magnets for wind turbines to designer semiconductors for solar cells; to the invention of technologies that improve human health, from metal alloys for lightweight prosthetics to polymer matrices for controlled drug release; to progress in intra- and interplanetary travel within realms of objective and virtual reality alike, from high-efficiency batteries for emissions-free vehicles, to carbon composites for fuel-efficient spacecraft, to atomically thin films for high-speed integrated circuits. This Special Feature on Novel Materials presents a collection of perspectives articles, short reviews, and original research papers designed to capture some of the breadth and excitement in recent materials research. This representative set of topics intersects critical areas in electronics, biology, advanced manufacturing, and chemical … [↵][1]1To whom correspondence may be addressed. Email: jrogers{at}northwestern.edu or desimone{at}email.unc.edu. [1]: #xref-corresp-1-1}, number={42}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Rogers, John A. and DeSimone, Joseph M.}, year={2016}, month={Oct}, pages={11667–11669} } @article{desimone_mecham_farrell_2016, title={Organic Polymer Chemistry in the Context of Novel Processes}, volume={2}, ISSN={["2374-7951"]}, DOI={10.1021/acscentsci.6b00195}, abstractNote={This article was written to shed light on a series of what some have stated are not so obvious connections that link polymer synthesis in supercritical CO2 to cancer treatment and vaccines, nonflammable polymer electrolytes for lithium ion batteries, and 3D printing. In telling this story, we also attempt to show the value of versatility in applying one’s primary area of expertise to address pertinent questions in science and in society. In this Outlook, we attempted to identify key factors to enable a versatile and nimble research effort to take shape in an effort to influence diverse fields and have a tangible impact in the private sector through the translation of discoveries into the marketplace.}, number={9}, journal={ACS CENTRAL SCIENCE}, author={DeSimone, Joseph M. and Mecham, Sue J. and Farrell, Crista L.}, year={2016}, month={Sep}, pages={588–597} } @article{metz_tian_hoekstra_yi_stone_horvath_miley_desimone_luft_silva_2016, title={Precisely Molded Nanoparticle Displaying DENV-E Proteins Induces Robust Serotype-Specific Neutralizing Antibody Responses}, volume={10}, ISSN={["1935-2735"]}, DOI={10.1371/journal.pntd.0005071}, abstractNote={Dengue virus (DENV) is the causative agent of dengue fever and dengue hemorrhagic fever. The virus is endemic in over 120 countries, causing over 350 million infections per year. Dengue vaccine development is challenging because of the need to induce simultaneous protection against four antigenically distinct DENV serotypes and evidence that, under some conditions, vaccination can enhance disease due to specific immunity to the virus. While several live-attenuated tetravalent dengue virus vaccines display partial efficacy, it has been challenging to induce balanced protective immunity to all 4 serotypes. Instead of using whole-virus formulations, we are exploring the potentials for a particulate subunit vaccine, based on DENV E-protein displayed on nanoparticles that have been precisely molded using Particle Replication in Non-wetting Template (PRINT) technology. Here we describe immunization studies with a DENV2-nanoparticle vaccine candidate. The ectodomain of DENV2-E protein was expressed as a secreted recombinant protein (sRecE), purified and adsorbed to poly (lactic-co-glycolic acid) (PLGA) nanoparticles of different sizes and shape. We show that PRINT nanoparticle adsorbed sRecE without any adjuvant induces higher IgG titers and a more potent DENV2-specific neutralizing antibody response compared to the soluble sRecE protein alone. Antigen trafficking indicate that PRINT nanoparticle display of sRecE prolongs the bio-availability of the antigen in the draining lymph nodes by creating an antigen depot. Our results demonstrate that PRINT nanoparticles are a promising platform for delivering subunit vaccines against flaviviruses such as dengue and Zika.}, number={10}, journal={PLOS NEGLECTED TROPICAL DISEASES}, author={Metz, Stefan W. and Tian, Shaomin and Hoekstra, Gabriel and Yi, Xianwen and Stone, Michelle and Horvath, Katie and Miley, Michael J. and DeSimone, Joseph and Luft, Chris J. and Silva, Aravinda M.}, year={2016}, month={Oct} } @article{rahhal_fromen_wilson_kai_shen_luft_desimone_2016, title={Pulmonary Delivery of Butyrylcholinesterase as a Model Protein to the Lung}, volume={13}, ISSN={["1543-8384"]}, DOI={10.1021/acs.molpharmaceut.6b00066}, abstractNote={Pulmonary delivery has great potential for delivering biologics to the lung if the challenges of maintaining activity, stability, and ideal aerosol characteristics can be overcome. To study the interactions of a biologic in the lung, we chose butyrylcholinesterase (BuChE) as our model enzyme, which has application for use as a bioscavenger protecting against organophosphate exposure or for use with pseudocholinesterase deficient patients. In mice, orotracheal administration of free BuChE resulted in 72 h detection in the lungs and 48 h in the broncheoalveolar lavage fluid (BALF). Free BuChE administered to the lung of all mouse backgrounds (Nude, C57BL/6, and BALB/c) showed evidence of an acute cytokine (IL-6, TNF-α, MIP2, and KC) and cellular immune response that subsided within 48 h, indicating relatively safe administration of this non-native biologic. We then developed a formulation of BuChE using Particle Replication in Non-Wetting Templates (PRINT). Aerosol characterization demonstrated biologically active BuChE 1 μm cylindrical particles with a mass median aerodynamic diameter of 2.77 μm, indicative of promising airway deposition via dry powder inhalers (DPI). Furthermore, particulate BuChE delivered via dry powder insufflation showed residence time of 48 h in the lungs and BALF. The in vivo residence time, immune response, and safety of particulate BuChE delivered via a pulmonary route, along with the cascade impaction distribution of dry powder PRINT BuChE, showed promise in the ability to deliver active enzymes with ideal deposition characteristics. These findings provide evidence for the feasibility of optimizing the use of BuChE in the clinic; PRINT BuChE particles can be readily formulated for use in DPIs, providing a convenient and effective treatment option.}, number={5}, journal={MOLECULAR PHARMACEUTICS}, author={Rahhal, Tojan B. and Fromen, Catherine A. and Wilson, Erin M. and Kai, Marc P. and Shen, Tammy W. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2016}, month={May}, pages={1626–1635} } @article{kapadia_tian_perry_luft_desimone_2016, title={Reduction Sensitive PEG Hydrogels for Codelivery of Antigen and Adjuvant To Induce Potent CTLs}, volume={13}, ISSN={1543-8384 1543-8392}, url={http://dx.doi.org/10.1021/acs.molpharmaceut.6b00288}, DOI={10.1021/acs.molpharmaceut.6b00288}, abstractNote={Educating our immune system via vaccination is an attractive approach to combat infectious diseases. Eliciting antigen specific cytotoxic T cells (CTLs), CD8+ effector T cells, is essential in controlling intracellular infectious diseases such as influenza (Flu), tuberculosis (TB), hepatitis, and HIV/AIDS, as well as tumors. However, vaccination utilizing subunit peptides to elicit a potent CD8+ T cell response with antigenic peptides is typically ineffective due to poor immunogenicity. Here we have engineered a reduction sensitive nanoparticle (NP) based subunit vaccine for intracellular delivery of an antigenic peptide and immunostimulatory adjuvant. We have co-conjugated an antigenic peptide (ovalbumin-derived CTL epitope [OVA257-264: SIINFEKL]) and an immunostimulatory adjuvant (CpG ODNs, TLR9 agonist) to PEG hydrogel NPs via a reduction sensitive linker. Bone-marrow derived dendritic cells (BMDCs) treated with the SIINFEKL conjugated NPs efficiently cross-presented the antigenic peptide via MHC-I surface receptor and induced proliferation of OT-I T cells. CpG ODN-conjugated NPs induced maturation of BMDCs as evidenced by the overexpression of CD80 and CD40 costimulatory receptors. Moreover, codelivery of NP conjugated SIINFEKL and CpG ODN significantly increased the frequency of IFN-γ producing CD8+ effector T cells in mice (∼6-fold improvement over soluble antigen and adjuvant). Furthermore, the NP subunit vaccine-induced effector T cells were able to kill up to 90% of the adoptively transferred antigenic peptide-loaded target cell. These results demonstrate that the reduction sensitive NP subunit vaccine elicits a potent CTL response and provide compelling evidence that this approach could be utilized to engineer particulate vaccines to deliver tumor or pathogen associated antigenic peptides to harness the immune system to fight against cancer and infectious diseases.}, number={10}, journal={Molecular Pharmaceutics}, publisher={American Chemical Society (ACS)}, author={Kapadia, Chintan H. and Tian, Shaomin and Perry, Jillian L. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2016}, month={Sep}, pages={3381–3394} } @article{chintapalli_timachova_olson_mecham_devaux_desimone_balsara_2016, title={Relationship between Conductivity, Ion Diffusion, and Transference Number in Perfluoropolyether Electrolytes}, volume={49}, ISSN={["1520-5835"]}, DOI={10.1021/acs.macromol.6b00412}, abstractNote={Connecting continuum-scale ion transport properties such as conductivity and cation transference number to microscopic transport properties such as ion dissociation and ion self-diffusivities is an unresolved challenge in characterizing polymer electrolytes. Better understanding of the relationship between microscopic and continuum scale transport properties would enable the rational design of improved electrolytes for applications such as lithium batteries. We present measurements of continuum and microscopic ion transport properties of nonflammable liquid electrolytes consisting of binary mixtures of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and perfluoropolyethers (PFPE) with different end groups: diol, dimethyl carbonate, ethoxy–diol, and ethoxy–dimethyl carbonate. The continuum properties, conductivity and cation transference number, were measured by ac impedance spectroscopy and potentiostatic polarization, respectively. The ion self-diffusivities were measured by pulsed field gradient nuc...}, number={9}, journal={MACROMOLECULES}, author={Chintapalli, Mahati and Timachova, Ksenia and Olson, Kevin R. and Mecham, Sue J. and Devaux, Didier and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2016}, month={May}, pages={3508–3515} } @article{johnson_caudill_tumbleston_bloomquist_moga_ermoshkin_shirvanyants_mecham_luft_desimone_2016, title={Single-Step Fabrication of Computationally Designed Microneedles by Continuous Liquid Interface Production}, volume={11}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0162518}, abstractNote={Microneedles, arrays of micron-sized needles that painlessly puncture the skin, enable transdermal delivery of medications that are difficult to deliver using more traditional routes. Many important design parameters, such as microneedle size, shape, spacing, and composition, are known to influence efficacy, but are notoriously difficult to alter due to the complex nature of microfabrication techniques. Herein, we utilize a novel additive manufacturing (“3D printing”) technique called Continuous Liquid Interface Production (CLIP) to rapidly prototype sharp microneedles with tuneable geometries (size, shape, aspect ratio, spacing). This technology allows for mold-independent, one-step manufacturing of microneedle arrays of virtually any design in less than 10 minutes per patch. Square pyramidal CLIP microneedles composed of trimethylolpropane triacrylate, polyacrylic acid and photopolymerizable derivatives of polyethylene glycol and polycaprolactone were fabricated to demonstrate the range of materials that can be utilized within this platform for encapsulating and controlling the release of therapeutics. These CLIP microneedles effectively pierced murine skin ex vivo and released the fluorescent drug surrogate rhodamine.}, number={9}, journal={PLOS ONE}, author={Johnson, Ashley R. and Caudill, Cassie L. and Tumbleston, John R. and Bloomquist, Cameron J. and Moga, Katherine A. and Ermoshkin, Alexander and Shirvanyants, David and Mecham, Sue J. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2016}, month={Sep} } @article{roode_brighton_bo_perry_parrott_kersey_luft_bear_desimone_davis_2016, title={Subtumoral analysis of PRINT nanoparticle distribution reveals targeting variation based on cellular and particle properties}, volume={12}, ISSN={1549-9634}, url={http://dx.doi.org/10.1016/j.nano.2015.12.382}, DOI={10.1016/j.nano.2015.12.382}, abstractNote={The biological activity of nanoparticle-directed therapies critically depends on cellular targeting. We examined the subtumoral fate of Particle Replication in Non-Wetting Templates (PRINT) nanoparticles in a xenografted melanoma tumor model by multi-color flow cytometry and in vivo confocal tumor imaging. These approaches were compared with the typical method of whole-organ quantification by radiolabeling. In contrast to radioactivity based detection which demonstrated a linear dose-dependent accumulation in the organ, flow cytometry revealed that particle association with cancer cells became dose-independent with increased particle doses and that the majority of the nanoparticles in the tumor were associated with cancer cells despite a low fractional association. In vivo imaging demonstrated an inverse relationship between tumor cell association and other immune cells, likely macrophages. Finally, variation in particle size nonuniformly affected subtumoral association. This study demonstrates the importance of subtumoral targeting when assessing nanoparticle activity within tumors. Particle Replication in Non-Wetting Templates (PRINT) technology allows the production of nanoparticles with uniform size. The authors in the study utilized PRINT-produced nanoparticles to investigate specific tumor uptake by multi-color flow cytometry and in vivo confocal tumor imaging. This approach allowed further in-depth correlation between nanoparticle properties and tumor cells and should improve future design.}, number={4}, journal={Nanomedicine: Nanotechnology, Biology and Medicine}, publisher={Elsevier BV}, author={Roode, Luke E. and Brighton, Hailey and Bo, Tao and Perry, Jillian L. and Parrott, Matthew C. and Kersey, Farrell and Luft, J. Chris and Bear, James E. and DeSimone, Joseph M. and Davis, Ian J.}, year={2016}, month={May}, pages={1053–1062} } @article{robbins_roberts_guo_reuter_shen_sempowski_mckinnon_su_desimone_ting_2015, title={Analysis of human innate immune responses to PRINT fabricated nanoparticles with cross validation using a humanized mouse model}, volume={11}, ISSN={1549-9634}, url={http://dx.doi.org/10.1016/j.nano.2014.11.010}, DOI={10.1016/j.nano.2014.11.010}, abstractNote={Ideal nanoparticle (NP)-based drug and vaccine delivery vectors should be free of inherent cytotoxic or immunostimulatory properties. Therefore, determining baseline immune responses to nanomaterials is of utmost importance when designing human therapeutics. We characterized the response of human immune cells to hydrogel NPs fabricated using Particle Replication in Non-wetting Templates (PRINT) technology. We found preferential NP uptake by primary CD14+ monocytes, which was significantly reduced upon PEGylation of the NP surface. Multiplex cytokine analysis of NP treated primary human peripheral blood mononuclear cells suggests that PRINT based hydrogel NPs do not evoke significant inflammatory responses nor induce cytotoxicity or complement activation. We furthered these studies using an in vivo humanized mouse model and similarly found preferential NP uptake by human CD14+ monocytes without systemic inflammatory cytokine responses. These studies suggest that PRINT hydrogel particles form a desirable platform for vaccine and drug delivery as they neither induce inflammation nor toxicity. The authors here fabricated hydrogel nanorods using the PRINT (Particle Replication In Nonwetting Templates) fabrication process. They tested the interaction of human immune cells with these particles and found no immunoreactivity. This finding would suggest that monodisperse PRINT particles of identical shape and size could serve a variety of clinical applications.}, number={3}, journal={Nanomedicine: Nanotechnology, Biology and Medicine}, publisher={Elsevier BV}, author={Robbins, Gregory R. and Roberts, Reid A. and Guo, Haitao and Reuter, Kevin and Shen, Tammy and Sempowski, Gregory D. and McKinnon, Karen P. and Su, Lishan and DeSimone, Joseph M. and Ting, Jenny P.-Y.}, year={2015}, month={Apr}, pages={589–599} } @article{phanse_dunphy_perry_airs_paquette_carlson_xu_luft_desimone_beaty_et al._2015, title={Biodistribution and Toxicity Studies of PRINT Hydrogel Nanoparticles in Mosquito Larvae and Cells}, volume={9}, ISSN={["1935-2735"]}, DOI={10.1371/journal.pntd.0003735}, abstractNote={Mosquito-borne diseases continue to remain major threats to human and animal health and impediments to socioeconomic development. Increasing mosquito resistance to chemical insecticides is a great public health concern, and new strategies/technologies are necessary to develop the next-generation of vector control tools. We propose to develop a novel method for mosquito control that employs nanoparticles (NPs) as a platform for delivery of mosquitocidal dsRNA molecules to silence mosquito genes and cause vector lethality. Identifying optimal NP chemistry and morphology is imperative for efficient mosquitocide delivery. Toward this end, fluorescently labeled polyethylene glycol NPs of specific sizes, shapes (80 nm x 320 nm, 80 nm x 5000 nm, 200 nm x 200 nm, and 1000 nm x 1000 nm) and charges (negative and positive) were fabricated by Particle Replication in Non-Wetting Templates (PRINT) technology. Biodistribution, persistence, and toxicity of PRINT NPs were evaluated in vitro in mosquito cell culture and in vivo in Anopheles gambiae larvae following parenteral and oral challenge. Following parenteral challenge, the biodistribution of the positively and negatively charged NPs of each size and shape was similar; intense fluorescence was observed in thoracic and abdominal regions of the larval body. Positively charged NPs were more associated with the gastric caeca in the gastrointestinal tract. Negatively charged NPs persisted through metamorphosis and were observed in head, body and ovaries of adults. Following oral challenge, NPs were detected in the larval mid- and hindgut. Positively charged NPs were more efficiently internalized in vitro than negatively charged NPs. Positively charged NPs trafficked to the cytosol, but negatively charged NPs co-localized with lysosomes. Following in vitro and in vivo challenge, none of the NPs tested induced any cytotoxic effects.}, number={5}, journal={PLOS NEGLECTED TROPICAL DISEASES}, author={Phanse, Yashdeep and Dunphy, Brendan M. and Perry, Jillian L. and Airs, Paul M. and Paquette, Cynthia C. H. and Carlson, Jonathan O. and Xu, Jing and Luft, J. Christopher and DeSimone, Joseph M. and Beaty, Barry J. and et al.}, year={2015}, month={May} } @article{paquette_phanse_perry_sanchez-vargas_airs_dunphy_xu_carlson_luft_desimone_et al._2015, title={Biodistribution and Trafficking of Hydrogel Nanoparticles in Adult Mosquitoes}, volume={9}, ISSN={["1935-2735"]}, DOI={10.1371/journal.pntd.0003745}, abstractNote={Background Nanotechnology offers great potential for molecular genetic investigations and potential control of medically important arthropods. Major advances have been made in mammalian systems to define nanoparticle (NP) characteristics that condition trafficking and biodistribution of NPs in the host. Such information is critical for effective delivery of therapeutics and molecules to cells and organs, but little is known about biodistribution of NPs in mosquitoes. Methodology/Principal Findings PRINT technology was used to construct a library of fluorescently labeled hydrogel NPs of defined size, shape, and surface charge. The biodistribution (organ, tissue, and cell tropisms and trafficking kinetics) of positively and negatively charged 200 nm x 200 nm, 80 nm x 320 nm, and 80 nm x 5000 nm NPs was determined in adult Anopheles gambiae mosquitoes as a function of the route of challenge (ingestion, injection or contact) using whole body imaging and fluorescence microscopy. Mosquitoes readily ingested NPs in sugar solution. Whole body fluorescence imaging revealed substantial NP accumulation (load) in the alimentary tracts of the adult mosquitoes, with the greatest loads in the diverticula, cardia and foregut. Positively and negatively charged NPs differed in their biodistribution and trafficking. Following oral challenge, negatively charged NPs transited the alimentary tract more rapidly than positively charged NPs. Following contact challenge, negatively charged NPs trafficked more efficiently in alimentary tract tissues. Following parenteral challenge, positively and negatively charged NPs differed in tissue tropisms and trafficking in the hemocoel. Injected NPs were also detected in cardia/foregut, suggesting trafficking of NPs from the hemocoel into the alimentary tract. Conclusions/Significance Herein we have developed a tool box of NPs with the biodistribution and tissue tropism characteristics for gene structure/function studies and for delivery of vector lethal cargoes for mosquito control.}, number={5}, journal={PLOS NEGLECTED TROPICAL DISEASES}, author={Paquette, Cynthia C. H. and Phanse, Yashdeep and Perry, Jillian L. and Sanchez-Vargas, Irma and Airs, Paul M. and Dunphy, Brendan M. and Xu, Jing and Carlson, Jonathan O. and Luft, J. Christopher and DeSimone, Joseph M. and et al.}, year={2015}, month={May} } @inbook{perry_kai_reuter_bowerman_christopher luft_desimone_2015, title={Calibration-Quality Cancer Nanotherapeutics}, ISBN={9783319165547 9783319165554}, ISSN={0927-3042}, url={http://dx.doi.org/10.1007/978-3-319-16555-4_12}, DOI={10.1007/978-3-319-16555-4_12}, abstractNote={Nanoparticle properties such as size, shape, deformability, and surface chemistry all play a role in nanomedicine drug delivery in cancer. While many studies address the behavior of particle systems in a biological setting, revealing how these properties work together presents unique challenges on the nanoscale. "Calibration-quality" control over such properties is needed to draw adequate conclusions that are independent of parameter variability. Furthermore, active targeting and drug loading strategies introduce even greater complexities via their potential to alter particle pharmacokinetics. Ultimately, the investigation and optimization of particle properties should be carried out in the appropriate preclinical tumor model. In doing so, translational efficacy improves as clinical tumor properties increase. Looking forward, the field of nanomedicine will continue to have significant clinical impacts as the capabilities of nanoparticulate drug delivery are further enhanced.}, booktitle={Cancer Treatment and Research}, publisher={Springer International Publishing}, author={Perry, Jillian L. and Kai, Marc P. and Reuter, Kevin G. and Bowerman, Charles and Christopher Luft, J. and DeSimone, Joseph M.}, year={2015}, pages={275–291} } @article{villaluenga_wujcik_tong_devaux_wong_desimone_balsara_2016, title={Compliant glass-polymer hybrid single ion-conducting electrolytes for lithium batteries}, volume={113}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1520394112}, abstractNote={Significance This study describes hybrid single ion-conducting electrolytes based on inorganic sulfide glasses and perfluoropolyether polymers for lithium batteries. Herein, it is shown that hybrid electrolytes provide a compelling alternative to the traditional glass, ceramic, or polymer battery electrolytes. These electrolytes present high transference numbers, unprecedented ionic conductivities at room temperature, and excellent electrochemical stability, and they limit the dissolution of lithium polysulfides. The results in this work represent a significant step toward addressing the challenges of enabling the next generation cathodes, such as lithium nickel manganese cobalt oxide and sulfur.}, number={1}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Villaluenga, Irune and Wujcik, Kevin H. and Tong, Wei and Devaux, Didier and Wong, Dominica H. C. and DeSimone, Joseph M. and Balsara, Nitash P.}, year={2016}, month={Jan}, pages={52–57} } @article{tumbleston_shirvanyants_ermoshkin_janusziewicz_johnson_kelly_chen_pinschmidt_rolland_ermoshkin_et al._2015, title={Continuous liquid interface production of 3D objects}, volume={347}, ISSN={["1095-9203"]}, DOI={10.1126/science.aaa2397}, abstractNote={Fast, continuous, 3D printing Although three-dimensional (3D) printing is now possible using relatively small and low-cost machines, it is still a fairly slow process. This is because 3D printers require a series of steps to cure, replenish, and reposition themselves for each additive cycle. Tumbleston et al. devised a process to effectively grow solid structures out of a liquid bath. The key to the process is the creation of an oxygen-containing “dead zone” between the solid part and the liquid precursor where solidification cannot occur. The precursor liquid is then renewed by the upward movement of the growing solid part. This approach made structures tens of centimeters in size that could contain features with a resolution below 100 µm. Science , this issue p. 1349 }, number={6228}, journal={SCIENCE}, author={Tumbleston, John R. and Shirvanyants, David and Ermoshkin, Nikita and Janusziewicz, Rima and Johnson, Ashley R. and Kelly, David and Chen, Kai and Pinschmidt, Robert and Rolland, Jason P. and Ermoshkin, Alexander and et al.}, year={2015}, month={Mar}, pages={1349–1352} } @article{shen_fromen_kai_luft_rahhal_robbins_desimone_2015, title={Distribution and Cellular Uptake of PEGylated Polymeric Particles in the Lung Towards Cell-Specific Targeted Delivery}, volume={32}, ISSN={0724-8741 1573-904X}, url={http://dx.doi.org/10.1007/s11095-015-1701-7}, DOI={10.1007/s11095-015-1701-7}, abstractNote={We evaluated the role of a poly(ethylene glycol) (PEG) surface coating to increase residence times and alter the cellular fate of nano- and microparticles delivered to the lung. Three sizes of PRINT hydrogel particles (80 × 320 nm, 1.5 and 6 μm donuts) with and without a surface PEG coating were instilled in the airways of C57/b6 mice. At time points of 1, 7, and 28 days, BALF and whole lungs were evaluated for the inflammatory cytokine Il-6 and chemokine MIP-2, histopathology, cellular populations of macrophages, dendritic cells (DCs), and granulocytes, and particulate uptake within these cells through flow cytometry, ELISAs, and fluorescent imaging. Particles of all sizes and surface chemistries were readily observed in the lung with minimal inflammatory response at all time points. Surface modification with PEGylation was found to significantly increase lung residence times and homogeneous lung distribution, delaying macrophage clearance of all sizes, with the largest increase in residence time observed for 80 × 320 nm particles. Additionally, it was observed that DCs were recruited to the airway following administration of unPEGylated particles and preferentially associated with these particles. Pulmonary drug delivery vehicles designed with a PEG surface coating can be used to delay particle uptake and promote cell-specific targeting of therapeutics.}, number={10}, journal={Pharmaceutical Research}, publisher={Springer Science and Business Media LLC}, author={Shen, Tammy W. and Fromen, Catherine A. and Kai, Marc P. and Luft, J. Christopher and Rahhal, Tojan B. and Robbins, Gregory R. and DeSimone, Joseph M.}, year={2015}, month={May}, pages={3248–3260} } @article{kai_keeler_perry_reuter_luft_sara k. o'neal_zamboni_desimone_2015, title={Evaluation of drug loading, pharmacokinetic behavior, and toxicity of a cisplatin-containing hydrogel nanoparticle}, volume={204}, ISSN={["1873-4995"]}, DOI={10.1016/j.jconrel.2015.03.001}, abstractNote={Cisplatin is a cytotoxic drug used as a first-line therapy for a wide variety of cancers. However, significant renal and neurological toxicities limit its clinical use. It has been documented that drug toxicities can be mitigated through nanoparticle formulation, while simultaneously increasing tumor accumulation through the enhanced permeation and retention effect. Circulation persistence is a key characteristic for exploiting this effect, and to that end we have developed long-circulating, PEGylated, polymeric hydrogels using the Particle Replication In Non-wetting Templates (PRINT®) platform and complexed cisplatin into the particles (PRINT-Platin). Sustained release was demonstrated, and drug loading correlated to surface PEG density. A PEG Mushroom conformation showed the best compromise between particle pharmacokinetic (PK) parameters and drug loading (16 wt.%). While the PK profile of PEG Brush was superior, the loading was poor (2 wt.%). Conversely, the drug loading in non-PEGylated particles was better (20 wt.%), but the PK was not desirable. We also showed comparable cytotoxicity to cisplatin in several cancer cell lines (non-small cell lung, A549; ovarian, SKOV-3; breast, MDA-MB-468) and a higher MTD in mice (10 mg/kg versus 5 mg/kg). The pharmacokinetic profiles of drug in plasma, tumor, and kidney indicate improved exposure in the blood and tumor accumulation, with concurrent renal protection, when cisplatin was formulated in a nanoparticle. PK parameters were markedly improved: a 16.4-times higher area-under-the-curve (AUC), a reduction in clearance (CL) by a factor of 11.2, and a 4.20-times increase in the volume of distribution (Vd). Additionally, non-small cell lung and ovarian tumor AUC was at least twice that of cisplatin in both models. These findings suggest the potential for PRINT-Platin to improve efficacy and reduce toxicity compared to current cisplatin therapies.}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Kai, Marc P. and Keeler, Amanda W. and Perry, Jillian L. and Reuter, Kevin G. and Luft, J. Christopher and Sara K. O'Neal and Zamboni, William C. and DeSimone, Joseph M.}, year={2015}, month={Apr}, pages={70–77} } @article{byrne_jajja_adrian t. o'neill_bickford_keeler_hyder_wagner_deal_little_moffitt_et al._2015, title={Local iontophoretic administration of cytotoxic therapies to solid tumors}, volume={7}, ISSN={["1946-6242"]}, DOI={10.1126/scitranslmed.3009951}, abstractNote={Local administration of cytotoxic drugs using iontophoresis results in drug accumulation and therapeutic efficacy in mouse models of pancreatic and breast cancer and favorable PK in a large animal model.}, number={273}, journal={SCIENCE TRANSLATIONAL MEDICINE}, author={Byrne, James D. and Jajja, Mohammad R. N. and Adrian T. O'Neill and Bickford, Lissett R. and Keeler, Amanda W. and Hyder, Nabeel and Wagner, Kyle and Deal, Allison and Little, Ryan E. and Moffitt, Richard A. and et al.}, year={2015}, month={Feb} } @article{kapadia_perry_tian_luft_desimone_2015, title={Nanoparticulate immunotherapy for cancer}, volume={219}, ISSN={["1873-4995"]}, DOI={10.1016/j.jconrel.2015.09.062}, abstractNote={Although surgery, radiation therapy, and chemotherapy have significantly improved as treatments for cancer, they can rarely control metastatic disease and cures remain scarce. Promising recent developments suggest that cancer immunotherapy may become a powerful new therapy that clinicians can offer cancer patients. The opportunity to orchestrate the body's own immune system to target, fight, and eradicate cancer cells without destroying healthy cells makes this an extremely attractive treatment modality. Our increased knowledge in anti-tumor immunity and the immunosuppressive tumor microenvironment (TME) has provided many therapeutic strategies to battle cancer. That combined with advancements in the field of particulate delivery systems provide a mechanism to deliver these immunotherapeutics to their specific targeted cells and the TME. In this review we will focus on the current status of immunotherapy and the potential advantages of utilizing nanocarriers within the field.}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Kapadia, Chintan H. and Perry, Jillian L. and Tian, Shaomin and Luft, J. Christopher and DeSimone, Joseph M.}, year={2015}, month={Dec}, pages={167–180} } @article{sharpe_malinowski_sorana_luft_bowerman_desimone_johnson_2015, title={Preparation and biological evaluation of synthetic and polymer-encapsulated congeners of the antitumor agent pactamycin: Insight into functional group effects and biological activity}, volume={23}, ISSN={["1464-3391"]}, DOI={10.1016/j.bmc.2015.02.022}, abstractNote={The synthesis and biological analysis of a number of novel congeners of the aminocyclopentitol pactamycin is described. Specific attention was paid to the preparation of derivatives at crucial synthetic branch points of the parent structure, and biological assays revealed a number of insights into the source of pactamycin’s biological activity. Additionally, the encapsulation of pactamycin and select derivatives into the PRINT© nanoparticle technology was investigated as a proof-of-concept, and evidence of bioactivity modulation through nanoparticle delivery is demonstrated. This work has provided heretofore unrealized access to a large number of novel compounds for further evaluation.}, number={8}, journal={BIOORGANIC & MEDICINAL CHEMISTRY}, author={Sharpe, Robert J. and Malinowski, Justin T. and Sorana, Federico and Luft, J. Christopher and Bowerman, Charles J. and DeSimone, Joseph M. and Johnson, Jeffrey S.}, year={2015}, month={Apr}, pages={1849–1857} } @article{mueller_tian_desimone_2015, title={Rapid and Persistent Delivery of Antigen by Lymph Node Targeting PRINT Nanoparticle Vaccine Carrier To Promote Humoral Immunity}, volume={12}, ISSN={["1543-8384"]}, DOI={10.1021/mp500589c}, abstractNote={Nanoparticle delivery of subunit vaccines may increase vaccine efficacy, leading to a wide variety of safe and effective vaccines beyond those available through dosing inactivated or live, attenuated whole pathogens. Here we present a versatile vaccine delivery platform based on PRINT hydrogels made of biocompatible hydroxy-poly(ethylene glycol) (PEG) that is able to activate the complement system by the alternative pathway. These lymph node targeting nanoparticles (NPs) promote the immunogenicity of a model antigen, ovalbumin, showing comparable adjuvant effect to alum. We demonstrate that an antigen-specific humoral response is correlated with antigen delivery to the draining lymph nodes, in particular, B cell rich regions of the lymph nodes. 80 × 180 nm cylindrical NPs were able to sustain prolonged antigen presentation to antigen presenting cells (APCs) and elicit a stronger immune response than nondraining 1 × 1 μm NPs or rapidly clearing soluble antigen. The 80 × 180 nm NPs also show high levels of uptake by key APCs and efficiently stimulate CD4(+) helper T cell proliferation in vivo, further promoting antibody production. These features together produce a significant humoral immune response, superior to that produced by free antigen alone. The simplicity of the chemistries used in antigen conjugation to PRINT NPs confers versatility to this antigen delivery platform, allowing for potential application to many infectious diseases.}, number={5}, journal={MOLECULAR PHARMACEUTICS}, author={Mueller, Sarah N. and Tian, Shaomin and DeSimone, Joseph M.}, year={2015}, month={May}, pages={1356–1365} } @article{ma_tian_baryza_luft_desimone_2015, title={Reductively Responsive Hydrogel Nanoparticles with Uniform Size, Shape, and Tunable Composition for Systemic siRNA Delivery in Vivo}, volume={12}, ISSN={["1543-8384"]}, DOI={10.1021/acs.molpharmaceut.5b00054}, abstractNote={To achieve the great potential of siRNA based gene therapy, safe and efficient systemic delivery in vivo is essential. Here we report reductively responsive hydrogel nanoparticles with highly uniform size and shape for systemic siRNA delivery in vivo. "Blank" hydrogel nanoparticles with high aspect ratio were prepared using continuous particle fabrication based on PRINT (particle replication in nonwetting templates). Subsequently, siRNA was conjugated to "blank" nanoparticles via a disulfide linker with a high loading ratio of up to 18 wt %, followed by surface modification to enhance transfection. This fabrication process could be easily scaled up to prepare large quantity of hydrogel nanoparticles. By controlling hydrogel composition, surface modification, and siRNA loading ratio, siRNA conjugated nanoparticles were highly tunable to achieve high transfection efficiency in vitro. FVII-siRNA conjugated nanoparticles were further stabilized with surface coating for in vivo siRNA delivery to liver hepatocytes, and successful gene silencing was demonstrated at both mRNA and protein levels.}, number={10}, journal={MOLECULAR PHARMACEUTICS}, author={Ma, Da and Tian, Shaomin and Baryza, Jeremy and Luft, J. Christopher and DeSimone, Joseph M.}, year={2015}, month={Oct}, pages={3518–3526} } @article{reuter_perry_kim_luft_liu_desimone_2015, title={Targeted PRINT Hydrogels: The Role of Nanoparticle Size and Ligand Density on Cell Association, Biodistribution, and Tumor Accumulation}, volume={15}, ISSN={["1530-6992"]}, DOI={10.1021/acs.nanolett.5b01362}, abstractNote={In this Letter, we varied targeting ligand density of an EGFR binding affibody on the surface of two different hydrogel PRINT nanoparticles (80 nm × 320 and 55 nm × 60 nm) and monitored effects on target-cell association, off-target phagocytic uptake, biodistribution, and tumor accumulation. Interestingly, variations in ligand density only significantly altered in vitro internalization rates for the 80 nm × 320 nm particle. However, in vivo, both particle sizes experienced significant changes in biodistribution and pharmacokinetics as a function of ligand density. Overall, nanoparticle size and passive accumulation were the dominant factors eliciting tumor sequestration.}, number={10}, journal={NANO LETTERS}, author={Reuter, Kevin G. and Perry, Jillian L. and Kim, Dongwook and Luft, J. Christopher and Liu, Rihe and DeSimone, Joseph M.}, year={2015}, month={Oct}, pages={6371–6378} } @article{roberts_eitas_byrne_johnson_short_mckinnon_reisdorf_luft_desimone_ting_2015, title={Towards programming immune tolerance through geometric manipulation of phosphatidylserine}, volume={72}, ISSN={["1878-5905"]}, DOI={10.1016/j.biomaterials.2015.08.040}, abstractNote={The possibility of engineering the immune system in a targeted fashion using biomaterials such as nanoparticles has made considerable headway in recent years. However, little is known as to how modulating the spatial presentation of a ligand augments downstream immune responses. In this report we show that geometric manipulation of phosphatidylserine (PS) through fabrication on rod-shaped PLGA nanoparticles robustly dampens inflammatory responses from innate immune cells while promoting T regulatory cell abundance by impeding effector T cell expansion. This response depends on the geometry of PS presentation as both PS liposomes and 1 micron cylindrical PS-PLGA particles are less potent signal inducers than 80 × 320 nm rod-shaped PS-PLGA particles for an equivalent dose of PS. We show that this immune tolerizing effect can be co-opted for therapeutic benefit in a mouse model of multiple sclerosis and an assay of organ rejection using a mixed lymphocyte reaction with primary human immune cells. These data provide evidence that geometric manipulation of a ligand via biomaterials may enable more efficient and tunable programming of cellular signaling networks for therapeutic benefit in a variety of disease states, including autoimmunity and organ rejection, and thus should be an active area of further research.}, journal={BIOMATERIALS}, author={Roberts, Reid A. and Eitas, Timothy K. and Byrne, James D. and Johnson, Brandon M. and Short, Patrick J. and McKinnon, Karen P. and Reisdorf, Shannon and Luft, J. Christopher and DeSimone, Joseph M. and Ting, Jenny P.}, year={2015}, month={Dec}, pages={1–10} } @article{kai_brighton_fromen_shen_luft_luft_keeler_robbins_ting_zamboni_et al._2016, title={Tumor Presence Induces Global Immune Changes and Enhances Nanoparticle Clearance}, volume={10}, ISSN={["1936-086X"]}, DOI={10.1021/acsnano.5b05999}, abstractNote={Long-circulating nanoparticles are essential for increasing tumor accumulation to provide therapeutic efficacy. While it is known that tumor presence can alter the immune system, very few studies have explored this impact on nanoparticle circulation. In this report, we demonstrate how the presence of a tumor can change the local and global immune system, which dramatically increases particle clearance. We found that tumor presence significantly increased clearance of PRINT hydrogel nanoparticles from the circulation, resulting in increased accumulation in the liver and spleen, due to an increase in M2-like macrophages. Our findings highlight the need to better understand interactions between immune status and nanoparticle clearance, and suggest that further consideration of immune function is required for success in preclinical and clinical nanoparticle studies.}, number={1}, journal={ACS NANO}, author={Kai, Marc P. and Brighton, Hailey E. and Fromen, Catherine A. and Shen, Tammy W. and Luft, J. Christopher and Luft, Yancey E. and Keeler, Amanda W. and Robbins, Gregory R. and Ting, Jenny P. Y. and Zamboni, William C. and et al.}, year={2016}, month={Jan}, pages={861–870} } @article{finniss_chu_bowerman_luft_haroon_desimone_2014, title={A versatile acid-labile linker for antibody-drug conjugates}, volume={5}, ISSN={["2040-2511"]}, DOI={10.1039/c4md00150h}, abstractNote={Silyl ether chemistry was used as the linker for an antibody drug conjugate to release a chemotherapeutic at low pH.}, number={9}, journal={MEDCHEMCOMM}, author={Finniss, Mathew C. and Chu, Kevin S. and Bowerman, Charles J. and Luft, J. Christopher and Haroon, Zishan A. and DeSimone, Joseph M.}, year={2014}, month={Sep}, pages={1355–1358} } @article{fromen_robbins_shen_kai_ting_desimone_2015, title={Controlled analysis of nanoparticle charge on mucosal and systemic antibody responses following pulmonary immunization}, volume={112}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1422923112}, abstractNote={Significance To our knowledge, no other nano-based vaccine delivery platform has directly assessed the effects of nanoparticle charge on pulmonary vaccination without affecting other physio/chemical particle characteristics and/or antigen loading. The Particle Replication in Non-Wetting Templates nanoparticle fabrication process is unique in that it allows for isolation of charge as the sole variable in these studies while maintaining all other physical and chemical parameters constant. We find that positively charged nanoparticles induce robust mucosal and systemic antibody responses following pulmonary administration, whereas negatively charged nanoparticles fail to do so. Therefore, our studies underscore the importance of considering nanoparticle charge as a critical design parameter when generating pulmonary-based vaccines and may have implications for particulate vaccination through other routes of administration.}, number={2}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Fromen, Catherine A. and Robbins, Gregory R. and Shen, Tammy W. and Kai, Marc P. and Ting, Jenny P. Y. and DeSimone, Joseph M.}, year={2015}, month={Jan}, pages={488–493} } @article{chen_xu_luft_tian_raval_desimone_2014, title={Design of Asymmetric Particles Containing a Charged Interior and a Neutral Surface Charge: Comparative Study on in Vivo Circulation of Polyelectrolyte Microgels}, volume={136}, ISSN={["0002-7863"]}, DOI={10.1021/ja503939n}, abstractNote={Lowering the modulus of hydrogel particles could enable them to bypass in vivo physical barriers that would otherwise filter particles with similar size but higher modulus. Incorporation of electrolyte moieties into the polymer network of hydrogel particles to increase the swelling ratio is a straightforward and quite efficient way to decrease the modulus. In addition, charged groups in hydrogel particles can also help secure cargoes. However, the distribution of charged groups on the surface of a particle can accelerate the clearance of particles. Herein, we developed a method to synthesize highly swollen microgels of precise size with near-neutral surface charge while retaining interior charged groups. A strategy was employed to enable a particle to be highly cross-linked with very small mesh size, and subsequently PEGylated to quench the exterior amines only without affecting the internal amines. Acidic degradation of the cross-linker allows for swelling of the particles to microgels with a desired size and deformability. The microgels fabricated demonstrated extended circulation in vivo compared to their counterparts with a charged surface, and could potentially be utilized in in vivo applications including as oxygen carriers or nucleic acid scavengers.}, number={28}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Chen, Kai and Xu, Jing and Luft, J. Christopher and Tian, Shaomin and Raval, Jay S. and DeSimone, Joseph M.}, year={2014}, month={Jul}, pages={9947–9952} } @article{desimone_farrell_2014, title={Driving Convergence with Human Diversity}, volume={6}, ISSN={["1946-6242"]}, DOI={10.1126/scitranslmed.3004486}, abstractNote={Convergent science will require human diversity—individuals with different backgrounds and life experiences—to drive it forward.}, number={238}, journal={SCIENCE TRANSLATIONAL MEDICINE}, author={DeSimone, Joseph M. and Farrell, Crista L.}, year={2014}, month={May} } @article{gharpure_chu_bowerman_miyake_pradeep_mangala_han_rupaimoole_armaiz-pena_rahhal_et al._2014, title={Metronomic docetaxel in PRINT® nanoparticles and EZH2 silencing have synergistic antitumor effect in ovarian cancer}, volume={13}, DOI={10.1158/1535-7163.MCT-13-0930}, abstractNote={Abstract The purpose of this study was to investigate the antitumor effects of a combination of metronomic doses of a novel delivery vehicle, PLGA-PRINT nanoparticles containing docetaxel, and antiangiogenic mEZH2 siRNA incorporated into chitosan nanoparticles. In vivo dose-finding studies and therapeutic experiments were conducted in well-established orthotopic mouse models of epithelial ovarian cancer. Antitumor effects were determined on the basis of reduction in mean tumor weight and number of metastatic tumor nodules in the animals. The tumor tissues from these in vivo studies were stained to evaluate the proliferation index (Ki67), apoptosis index (cleaved caspase 3), and microvessel density (CD31). The lowest dose of metronomic regimen (0.5 mg/kg) resulted in significant reduction in tumor growth. The combination of PLGA-PRINT-docetaxel and CH-mEZH2 siRNA showed significant antitumor effects in the HeyA8 and SKOV3ip1 tumor models (P < 0.05). Individual as well as combination therapies showed significant antiangiogenic, antiproliferative, and proapoptotic effects, and combination therapy had additive effects. Metronomic delivery of PLGA-PRINT-docetaxel combined with CH-mEZH2 siRNA has significant antitumor activity in preclinical models of ovarian cancer. Mol Cancer Ther; 13(7); 1750–7. ©2014 AACR.}, number={7}, journal={Molecular Cancer Therapeutics}, author={Gharpure, K.M. and Chu, K.S. and Bowerman, C. and Miyake, T. and Pradeep, S. and Mangala, S. and Han, Hee-Dong and Rupaimoole, R. and Armaiz-Pena, Guillermo N. and Rahhal, Tojan B. and et al.}, year={2014}, month={Jul}, pages={1750–1757} } @article{wong_thelen_fu_devaux_pandya_battaglia_balsara_desimone_2014, title={Nonflammable perfluoropolyether-based electrolytes for lithium batteries}, volume={111}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1314615111}, abstractNote={Significance This research article describes a unique class of nonflammable electrolytes for lithium-ion batteries that are based on functionalized perfluoropolyethers (PFPEs). It demonstrates that PFPEs may be used as a major component in operating batteries. These electrolytes not only are completely nonflammable, but they also exhibit unprecedented high transference numbers and low electrochemical polarization, indicative of longer battery life. The results in this work may represent a significant step toward a lithium-ion battery with improved safety and pave the way for the development of new electrolytes that can address the persisting challenges of current battery technologies.}, number={9}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Wong, Dominica H. C. and Thelen, Jacob L. and Fu, Yanbao and Devaux, Didier and Pandya, Ashish A. and Battaglia, Vincent S. and Balsara, Nitash P. and DeSimone, Joseph M.}, year={2014}, month={Mar}, pages={3327–3331} } @article{chu_finniss_schorzman_kuijer_luft_bowerman_napier_haroon_zamboni_desimone_2014, title={Particle Replication in Nonwetting Templates Nanoparticles with Tumor Selective Alkyl Silyl Ether Docetaxel Prodrug Reduces Toxicity}, volume={14}, ISSN={1530-6984 1530-6992}, url={http://dx.doi.org/10.1021/nl4046558}, DOI={10.1021/nl4046558}, abstractNote={Delivery systems designed to have triggered release after passively targeting the tumor may improve small molecule chemotherapeutic delivery. Particle replication in nonwetting templates was used to prepare nanoparticles to passively target solid tumors in an A549 subcutaneous xenograft model. An acid labile prodrug was delivered to minimize systemic free docetaxel concentrations and improve tolerability without compromising efficacy.}, number={3}, journal={Nano Letters}, publisher={American Chemical Society (ACS)}, author={Chu, Kevin S. and Finniss, Mathew C. and Schorzman, Allison N. and Kuijer, Jennifer L. and Luft, J. Christopher and Bowerman, Charles J. and Napier, Mary E. and Haroon, Zishan A. and Zamboni, William C. and DeSimone, Joseph M.}, year={2014}, month={Feb}, pages={1472–1476} } @article{wong_vitale_devaux_taylor_pandya_hallinan_thelen_mecham_lux_lapides_et al._2015, title={Phase Behavior and Electrochemical Characterization of Blends of Perfluoropolyether, Poly(ethylene glycol), and a Lithium Salt}, volume={27}, ISSN={["1520-5002"]}, DOI={10.1021/cm504228a}, abstractNote={Electrolytes consisting of low molecular weight perfluoropolyether (PFPE), poly(ethylene glycol) (PEG), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) blends were prepared and systematically studied for salt concentration and stoichiometry effects on the materials’ thermal and electrochemical properties. Herein we report that the tunable ratios of PFPE and PEG allow for precise control of crystalline melting and glass transition temperature properties. These blended liquid polymer electrolytes are inherently nonflammable and remain stable in the amorphous phase from approximately 150 °C down to −85 °C. The ionic conductivity of the electrolytes are on the order of 10–4 S/cm at 30 °C, which makes them suitable for rechargeable lithium batteries.}, number={2}, journal={CHEMISTRY OF MATERIALS}, author={Wong, Dominica H. C. and Vitale, Alessandra and Devaux, Didier and Taylor, Austria and Pandya, Ashish A. and Hallinan, Daniel T. and Thelen, Jacob L. and Mecham, Sue J. and Lux, Simon F. and Lapides, Alexander M. and et al.}, year={2015}, month={Jan}, pages={597–603} } @article{roberts_shen_allen_hasan_desimone_ting_2013, title={Analysis of the Murine Immune Response to Pulmonary Delivery of Precisely Fabricated Nano- and Microscale Particles}, volume={8}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0062115}, abstractNote={Nanomedicine has the potential to transform clinical care in the 21st century. However, a precise understanding of how nanomaterial design parameters such as size, shape and composition affect the mammalian immune system is a prerequisite for the realization of nanomedicine's translational promise. Herein, we make use of the recently developed Particle Replication in Non-wetting Template (PRINT) fabrication process to precisely fabricate particles across and the nano- and micro-scale with defined shapes and compositions to address the role of particle design parameters on the murine innate immune response in both in vitro and in vivo settings. We find that particles composed of either the biodegradable polymer poly(lactic-co-glycolic acid) (PLGA) or the biocompatible polymer polyethylene glycol (PEG) do not cause release of pro-inflammatory cytokines nor inflammasome activation in bone marrow-derived macrophages. When instilled into the lungs of mice, particle composition and size can augment the number and type of innate immune cells recruited to the lungs without triggering inflammatory responses as assayed by cytokine release and histopathology. Smaller particles (80×320 nm) are more readily taken up in vivo by monocytes and macrophages than larger particles (6 µm diameter), yet particles of all tested sizes remained in the lungs for up to 7 days without clearance or triggering of host immunity. These results suggest rational design of nanoparticle physical parameters can be used for sustained and localized delivery of therapeutics to the lungs.}, number={4}, journal={PLOS ONE}, author={Roberts, Reid A. and Shen, Tammy and Allen, Irving C. and Hasan, Warefta and DeSimone, Joseph M. and Ting, Jenny P. Y.}, year={2013}, month={Apr} } @article{galloway_murphy_desimone_di_herrmann_hunter_kindig_malinoski_rumley_stoltz_et al._2013, title={Development of a nanoparticle-based influenza vaccine using the PRINT® technology}, volume={9}, ISSN={1549-9634}, url={http://dx.doi.org/10.1016/j.nano.2012.11.001}, DOI={10.1016/j.nano.2012.11.001}, abstractNote={Historically it is known that presentation of vaccine antigens in particulate form, for a wide range of pathogens, has clear advantages over the presentation of soluble antigen alone [J.C. Aguilar, E.G. Rodriguez, Vaccine adjuvants revisited. Vaccine 25 (2007) 3752–3762, M. Singh, D. O'Hagan, Advances in vaccine adjuvants. Nature Biotechnology 17 (1999) 1075–1081]. Herein we describe a novel particle-based approach, which independently controls size, shape, and composition to control the delivery and presentation of vaccine antigen to the immune system. Highly uniform particles were produced using a particle molding technology called PRINT® (Particle Replication in Non-wetting Templates) which is an off-shoot of imprint lithography [J Am Chem Soc 127 (2005) 10096–10100, J Am Chem Soc 126 (2004) 2322–2323, Chem Soc Rev 35 (2006) 1095–1104, J Am Chem Soc 130 (2008) 5008–5009, J Am Chem Soc 130 (2008) 5438–5439, Polymer Reviews 47 (2007) 321–327, Acc Chem Res 41 (2008) 1685–1695, Acc Chem Res 44 (10) (2011) 990–998]. Cylindrical (diameter [d] = 80 nm, height [h] = 320 nm) poly (lactide-co-glycolide) (PLGA) based PRINT particles were designed to electrostatically bind commercial trivalent injectable influenza vaccine. In a variety of blended PLGA formulations, these particles were safe and showed enhanced responses to influenza hemagglutinin in murine models. Shape is one of the determining factors in interactions of nanoparticles with their biologic environment. PRINT technology is able to fabricate nearly uniform nanoparticles and this technology is tested here in murine models to effectively deliver influenza vaccine.}, number={4}, journal={Nanomedicine: Nanotechnology, Biology and Medicine}, publisher={Elsevier BV}, author={Galloway, Ashley L. and Murphy, Andrew and DeSimone, Joseph M. and Di, Jie and Herrmann, Jennifer P. and Hunter, Michael E. and Kindig, Jeffrey P. and Malinoski, Frank J. and Rumley, Megan A. and Stoltz, Daria M. and et al.}, year={2013}, month={May}, pages={523–531} } @misc{xu_wong_byrne_chen_bowerman_desimone_2013, title={Future of the Particle Replication in Nonwetting Templates (PRINT) Technology}, volume={52}, ISSN={["1521-3773"]}, DOI={10.1002/anie.201209145}, abstractNote={AbstractParticle replication in nonwetting templates (PRINT) is a continuous, roll‐to‐roll, high‐resolution molding technology which allows the design and synthesis of precisely defined micro‐ and nanoparticles. This technology adapts the lithographic techniques from the microelectronics industry and marries these with the roll‐to‐roll processes from the photographic film industry to enable researchers to have unprecedented control over particle size, shape, chemical composition, cargo, modulus, and surface properties. In addition, PRINT is a GMP‐compliant (GMP=good manufacturing practice) platform amenable for particle fabrication on a large scale. Herein, we describe some of our most recent work involving the PRINT technology for application in the biomedical and material sciences.}, number={26}, journal={ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, author={Xu, Jing and Wong, Dominica H. C. and Byrne, James D. and Chen, Kai and Bowerman, Charles and DeSimone, Joseph M.}, year={2013}, pages={6580–6589} } @article{dunn_byrne_perry_chen_desimone_2013, title={Generating Better Medicines for Cancer}, volume={2}, ISSN={["2161-1653"]}, DOI={10.1021/mz400116a}, abstractNote={The complexity of tumor biology warrants tailored drug delivery for overcoming the major challenges faced by cancer therapies. The versatility of the PRINT® (Particle Replication In Non-wetting Templates) process has enabled the preparation of shape- and size-specific particles with a wide range of chemical compositions and therapeutic cargos. Different particle matrices and drugs may be combined in a plug-and-play approach, such that physico-chemical characteristics of delivery vectors may be optimized for biocompatibility, cargo stability and release, circulation half-life, and efficacy. Thus, the engineering of particles for cancer therapy with specific biophysical behaviors and cellular responses has been demonstrated via the PRINT process.}, number={5}, journal={ACS MACRO LETTERS}, author={Dunn, Stuart S. and Byrne, James D. and Perry, Jillian L. and Chen, Kai and DeSimone, Joseph M.}, year={2013}, month={May}, pages={393–397} } @article{jones_roberts_robbins_perry_kai_chen_bo_napier_ting_desimone_et al._2013, title={Nanoparticle clearance is governed by Th1/Th2 immunity and strain background}, volume={123}, ISSN={["1558-8238"]}, DOI={10.1172/jci66895}, abstractNote={Extended circulation of nanoparticles in blood is essential for most clinical applications. Nanoparticles are rapidly cleared by cells of the mononuclear phagocyte system (MPS). Approaches such as grafting polyethylene glycol onto particles (PEGylation) extend circulation times; however, these particles are still cleared, and the processes involved in this clearance remain poorly understood. Here, we present an intravital microscopy-based assay for the quantification of nanoparticle clearance, allowing us to determine the effect of mouse strain and immune system function on particle clearance. We demonstrate that mouse strains that are prone to Th1 immune responses clear nanoparticles at a slower rate than Th2-prone mice. Using depletion strategies, we show that both granulocytes and macrophages participate in the enhanced clearance observed in Th2-prone mice. Macrophages isolated from Th1 strains took up fewer particles in vitro than macrophages from Th2 strains. Treating macrophages from Th1 strains with cytokines to differentiate them into M2 macrophages increased the amount of particle uptake. Conversely, treating macrophages from Th2 strains with cytokines to differentiate them into M1 macrophages decreased their particle uptake. Moreover, these results were confirmed in human monocyte-derived macrophages, suggesting that global immune regulation has a significant impact on nanoparticle clearance in humans.}, number={7}, journal={JOURNAL OF CLINICAL INVESTIGATION}, author={Jones, Stephen W. and Roberts, Reid A. and Robbins, Gregory R. and Perry, Jillian L. and Kai, Marc P. and Chen, Kai and Bo, Tao and Napier, Mary E. and Ting, Jenny P. Y. and DeSimone, Joseph M. and et al.}, year={2013}, month={Jul}, pages={3061–3073} } @article{chu_schorzman_finniss_bowerman_peng_luft_madden_wang_zamboni_desimone_2013, title={Nanoparticle drug loading as a design parameter to improve docetaxel pharmacokinetics and efficacy}, volume={34}, ISSN={["1878-5905"]}, DOI={10.1016/j.biomaterials.2013.07.038}, abstractNote={Nanoparticle (NP) drug loading is one of the key defining characteristics of an NP formulation. However, the effect of NP drug loading on therapeutic efficacy and pharmacokinetics has not been thoroughly evaluated. Herein, we characterized the efficacy, toxicity and pharmacokinetic properties of NP docetaxel formulations that have differential drug loading but are otherwise identical. Particle Replication in Non-wetting Templates (PRINT®), a soft-lithography fabrication technique, was used to formulate NPs with identical size, shape and surface chemistry, but with variable docetaxel loading. The lower weight loading (9%-NP) of docetaxel was found to have a superior pharmacokinetic profile and enhanced efficacy in a murine cancer model when compared to that of a higher docetaxel loading (20%-NP). The 9%-NP docetaxel increased plasma and tumor docetaxel exposure and reduced liver, spleen and lung exposure when compared to that of 20%-NP docetaxel.}, number={33}, journal={BIOMATERIALS}, author={Chu, Kevin S. and Schorzman, Allison N. and Finniss, Mathew C. and Bowerman, Charles J. and Peng, Lei and Luft, James C. and Madden, Andrew J. and Wang, Andrew Z. and Zamboni, William C. and DeSimone, Joseph M.}, year={2013}, month={Nov}, pages={8424–8429} } @article{petrosko_fromen_auyeung_desimone_mirkin_2013, title={Nanotechnology: An Enduring Bridge Between Engineering and Medicine}, journal={The Bridge: Linking Engineering and Society}, publisher={National Academy of Engineering}, author={Petrosko, S.H. and Fromen, C.A. and Auyeung, E. and DeSimone, J.M. and Mirkin, C.A.}, year={2013}, pages={7–15} } @inbook{byrne_hasan_blake_farrell_desimone_2013, place={New York}, title={PRINT Technology: A Versatile Platform for Novel Applications in Nanomedicine}, booktitle={Nanomaterials for Pharmaceutical Scientists}, publisher={Wiley}, author={Byrne, J.D. and Hasan, W. and Blake, S. and Farrell, C. and DeSimone, J.}, editor={Yin, S. and Wei, A.Editors}, year={2013} } @article{chu_hasan_rawal_walsh_enlow_luft_bridges_kuijer_napier_zamboni_et al._2013, title={Plasma, tumor and tissue pharmacokinetics of Docetaxel delivered via nanoparticles of different sizes and shapes in mice bearing SKOV-3 human ovarian carcinoma xenograft}, volume={9}, ISSN={1549-9634}, url={http://dx.doi.org/10.1016/j.nano.2012.11.008}, DOI={10.1016/j.nano.2012.11.008}, abstractNote={The particle fabrication technique PRINT® was used to fabricate monodisperse size and shape specific poly(lactide-co-glycolide) particles loaded with the chemotherapeutic Docetaxel. The pharmacokinetics of two cylindrical shaped particles with diameter=80nm; height=320nm (PRINT-Doc-80×320) and d=200nm; h=200nm (PRINT-Doc-200×200) were compared to Docetaxel in mice bearing human ovarian carcinoma SKOV-3 flank xenografts. The Docetaxel plasma exposure was ~20-fold higher for both particles compared to docetaxel. Additionally, the volume of distribution (Vd) of Docetaxel in PRINT formulations was ~18-fold (PRINT-Doc-80×320) and ~33-fold (PRINT-Doc-200×200) lower than Docetaxel. The prolonged duration of Docetaxel in plasma when dosed with PRINT formulations subsequently led to increased tumor exposure of Docetaxel from 0 to 168h (~53% higher for PRINT-Doc-80×320 and ~76% higher for PRINT-Doc-200×200 particles). PRINT-Doc-80×320 had lower exposures in the liver, spleen and lung compared with PRINT-Doc-200×200. Thus, the use of particles with smaller feature size may be preferred to decrease clearance by organs of the mononuclear phagocyte system.In this study, the plasma, tumor, and tissue pharmacokinetics of different Docetaxel nanoparticles of precise shape and size were characterized in mice with human ovarian carcinoma xenograft. It is concluded that the use of particles with smaller feature size may be preferred to decrease clearance by organs of the mononuclear phagocyte system.}, number={5}, journal={Nanomedicine: Nanotechnology, Biology and Medicine}, publisher={Elsevier BV}, author={Chu, Kevin S. and Hasan, Warefta and Rawal, Sumit and Walsh, Mark D. and Enlow, Elizabeth M. and Luft, J. Christopher and Bridges, Arlene S. and Kuijer, Jennifer L. and Napier, Mary E. and Zamboni, William C. and et al.}, year={2013}, month={Jul}, pages={686–693} } @article{xu_luft_yi_tian_owens_wang_johnson_berglund_smith_napier_et al._2013, title={RNA Replicon Delivery via Lipid-Complexed PRINT Protein Particles}, volume={10}, ISSN={["1543-8384"]}, DOI={10.1021/mp400190z}, abstractNote={Herein we report the development of a nonviral lipid-complexed PRINT (particle replication in nonwetting templates) protein particle system (LPP particle) for RNA replicon delivery with a view toward RNA replicon-based vaccination. Cylindrical bovine serum albumin (BSA) particles (diameter (d) 1 μm, height (h) 1 μm) loaded with RNA replicon and stabilized with a fully reversible disulfide cross-linker were fabricated using PRINT technology. Highly efficient delivery of the particles to Vero cells was achieved by complexing particles with a mixture of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) lipids. Our data suggest that (1) this lipid-complexed protein particle is a promising system for delivery of RNA replicon-based vaccines and (2) it is necessary to use a degradable cross-linker for successful delivery of RNA replicon via protein-based particles.}, number={9}, journal={MOLECULAR PHARMACEUTICS}, author={Xu, Jing and Luft, J. Christopher and Yi, Xianwen and Tian, Shaomin and Owens, Gary and Wang, Jin and Johnson, Ashley and Berglund, Peter and Smith, Jonathan and Napier, Mary E. and et al.}, year={2013}, month={Sep}, pages={3366–3374} } @article{moga_bickford_geil_dunn_pandya_wang_fain_archuleta_adrian t. o'neill_desimone_2013, title={Rapidly-Dissolvable Microneedle Patches Via a Highly Scalable and Reproducible Soft Lithography Approach}, volume={25}, ISSN={["1521-4095"]}, DOI={10.1002/adma.201300526}, abstractNote={Microneedle devices for transdermal drug delivery have recently become an attractive method to overcome the diffusion-limiting epidermis and effectively transport therapeutics to the body. Here, we demonstrate the fabrication of highly reproducible and completely dissolvable polymer microneedles on flexible water-soluble substrates. These biocompatible microneedles (made by using a soft lithography process known as PRINT) showed efficacy in piercing both murine and human skin samples and delivering a fluorescent drug surrogate to the tissue.}, number={36}, journal={ADVANCED MATERIALS}, author={Moga, Katherine A. and Bickford, Lissett R. and Geil, Robert D. and Dunn, Stuart S. and Pandya, Ashish A. and Wang, Yapei and Fain, John H. and Archuleta, Christine F. and Adrian T. O'Neill and DeSimone, Joseph M.}, year={2013}, month={Sep}, pages={5060–5066} } @article{morton_herlihy_shopsowitz_deng_chu_bowerman_desimone_hammond_2013, title={Scalable Manufacture of Built-to-Order Nanomedicine: Spray-Assisted Layer-by-Layer Functionalization of PRINT Nanoparticles}, volume={25}, ISSN={["1521-4095"]}, DOI={10.1002/adma.201302025}, abstractNote={Scalable methods, PRINT particle fabrication, and spray-assisted Layer-by-Layer deposition are combined to generate uniform and functional nanotechnologies with precise control over composition, size, shape, and surface functionality. A modular and tunable approach towards design of built-to-order nanoparticle systems, spray coating on PRINT particles is demonstrated to achieve technologies capable of targeted interactions with cancer cells for applications in drug delivery.}, number={34}, journal={ADVANCED MATERIALS}, author={Morton, Stephen W. and Herlihy, Kevin P. and Shopsowitz, Kevin E. and Deng, Zhou J. and Chu, Kevin S. and Bowerman, Charles J. and DeSimone, Joseph M. and Hammond, Paula T.}, year={2013}, month={Sep}, pages={4707–4713} } @article{fromen_shen_larus_mack_maynor_luft_desimone_2013, title={Synthesis and characterization of monodisperse uniformly shaped respirable aerosols}, volume={59}, ISSN={["1547-5905"]}, DOI={10.1002/aic.14157}, abstractNote={The top‐down, micromolding technique, referred to as Particle Replication in Nonwetting Templates (PRINT®), affords a new opportunity for the generation of inhalation therapeutics. Powders were fabricated with predetermined particle size and shape; when dispersed with a collision jet nebulizer, these particles resulted in monodisperse aerosols with geometric standard deviations well below 1.2. Dynamic shape factors for this novel set of uniformly shaped particles were determined by correcting the drag of nonspherical particles in the ultra‐Stokesian flow conditions of the aerodynamic particle sizer (APS). This convenient approach for shape factor determination agreed well with current literature approaches and allowed for the correction of APS results for particles with known volumes. Determined shape factor values of PRINT geometries were used to estimate the theoretical median aerodynamic diameters of individual aerosols, which were then compared to actual inhalation powders. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3184–3194, 2013}, number={9}, journal={AICHE JOURNAL}, author={Fromen, Catherine A. and Shen, Tammy W. and Larus, Abigail E. and Mack, Peter and Maynor, Benjamin W. and Luft, J. Christopher and DeSimone, Joseph M.}, year={2013}, month={Sep}, pages={3184–3194} } @article{desimone_goodenough_groves_bornscheuer_2012, title={Chevreul Medal for Uwe T. Bornscheuer}, volume={51}, ISSN={["1433-7851"]}, DOI={10.1002/anie.201204166}, abstractNote={Angewandte Chemie International EditionVolume 51, Issue 27 p. 6563-6563 News New Members of the National Academy of Sciences / Chevreul Medal: U. T. Bornscheuer First published: 13 June 2012 https://doi.org/10.1002/anie.201204166Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Graphical Abstract References 1aAngew. Chem. 2011, 123, 10194; Angew. Chem. Int. Ed. 2011, 50, 10018; 1bAngew. Chem. 2012, 5892; Angew. Chem. Int. Ed. 2012, 51, 5792; 1cAngew. Chem. 2011, 123, 7357; Angew. Chem. Int. Ed. 2011, 50, 7219. 2aJ. Wang, J. D. Byrne, M. E. Napier, J. M. DeSimone, Small 2011, 7, 1919; 2bM. J. Hampton, S. S. Williams, Z. Zhou, J. Nunes, D.-H. Ko, J. L. Templeton, E. T. Samulski, J. M. DeSimone, Adv. Mater. 2008, 20, 2667. 3J. B. Goodenough, Z. Anorg. Allg. Chem. 2012, DOI: . 4aR. N. Austin, K. Luddy, K. Erickson, M. Pender-Cudlip, E. Bertrand, D. Deng, R. S. Buzdygon, J. B. van Beilen, J. T. Groves, Angew. Chem. 2008, 120, 5310; Angew. Chem. Int. Ed. 2008, 47, 5232; 4bT. P. Umile, J. T. Groves, Angew. Chem. 2011, 123, 721; Angew. Chem. Int. Ed. 2011, 50, 695. 5aE. Fernández-Álvaro, R. Snajdrova, H. Jochens, T. Davids, D. Böttcher, U. T. Bornscheuer, Angew. Chem. 2011, 123, 8742; Angew. Chem. Int. Ed. 2011, 50, 8584; 5bH. B. Brundiek, A. S. Evitt, R. Kourist, U. T. Bornscheuer, Angew. Chem. 2012, 124, 425; Angew. Chem. Int. Ed. 2012, 51, 412. Volume51, Issue27July 2, 2012Pages 6563-6563 ReferencesRelatedInformation}, number={27}, journal={ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, author={DeSimone, J. M. and Goodenough, J. B. and Groves, J. T. and Bornscheuer, U. T.}, year={2012}, pages={6563–6563} } @article{kersey_merkel_perry_napier_desimone_2012, title={Effect of Aspect Ratio and Deformability on Nanoparticle Extravasation through Nanopores}, volume={28}, ISSN={["0743-7463"]}, DOI={10.1021/la301279v}, abstractNote={We describe the fabrication of filamentous hydrogel nanoparticles using a unique soft lithography based particle molding process referred to as PRINT (particle replication in nonwetting templates). The nanoparticles possess a constant width of 80 nm, and we varied their lengths ranging from 180 to 5000 nm. In addition to varying the aspect ratio of the particles, the deformability of the particles was tuned by varying the cross-link density within the particle matrix. Size characteristics such as hydrodynamic diameter and persistence length of the particles were analyzed using dynamic light scattering and electron microscopy techniques, respectively, while particle deformability was assessed by atomic force microscopy. Additionally, the ability of the particles to pass through membranes containing 0.2 μm pores was assessed by means of a simple filtration technique, and particle recovery was determined using fluorescence spectroscopy. The results show that particle recovery is mostly independent of aspect ratio at all cross-linker concentrations utilized, with the exception of 96 wt % PEG diacrylate 80 × 5000 nm particles, which showed the lowest percent recovery.}, number={23}, journal={LANGMUIR}, author={Kersey, Farrell R. and Merkel, Timothy J. and Perry, Jillian L. and Napier, Mary E. and DeSimone, Joseph M.}, year={2012}, month={Jun}, pages={8773–8781} } @misc{wang_byrne_napier_desimone_2012, title={Engineering nanomedicines using stimuli-responsive biomaterials}, volume={64}, ISSN={["1872-8294"]}, DOI={10.1016/j.addr.2012.01.003}, abstractNote={The ability to engineer particles has the potential to shift the paradigm in the creation of new medicines and diagnostics. Complete control over particle characteristics, such as size, shape, mechanical property, and surface chemistry, can enable rapid translation and facilitate the US Food and Drug Administration (FDA) approval of particle technologies for the treatment of cancer, infectious diseases, diabetes, and a host of other major illnesses. The incorporation of natural and artificial external stimuli to trigger the release of drugs enables exquisite control over the release profiles of drugs in a given environment. In this article, we examine several readily scalable top–down methods for the fabrication of shape-specific particles that utilize stimuli-responsive biomaterials for controlled drug delivery. Special attention is given to Particle Replication In Nonwetting Templates (PRINT®) technology and the application of novel triggered-release synthetic and natural polymers.}, number={11}, journal={ADVANCED DRUG DELIVERY REVIEWS}, author={Wang, Yapei and Byrne, James D. and Napier, Mary E. and DeSimone, Joseph M.}, year={2012}, month={Aug}, pages={1021–1030} } @article{parrott_finniss_luft_pandya_gullapalli_napier_desimone_2012, title={Incorporation and Controlled Release of Silyl Ether Prodrugs from PRINT Nanoparticles}, volume={134}, ISSN={["0002-7863"]}, DOI={10.1021/ja301710z}, abstractNote={Asymmetric bifunctional silyl ether (ABS) prodrugs of chemotherapeutics were synthesized and incorporated within 200 nm × 200 nm particles. ABS prodrugs of gemcitabine were selected as model compounds because of the difficulty to encapsulate a water-soluble drug within a hydrogel. The resulting drug delivery systems were degraded under acidic conditions and were found to release only the parent or active drug. Furthermore, changing the steric bulk of the alkyl substituents on the silicon atom could regulate the rate of drug release and, therefore, the intracellular toxicity of the gemcitabine-loaded particles. This yielded a family of novel nanoparticles that could be tuned to release drug over the course of hours, days, or months.}, number={18}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Parrott, Matthew C. and Finniss, Mathew and Luft, J. Chris and Pandya, Ashish and Gullapalli, Anuradha and Napier, Mary E. and Desimone, Joseph M.}, year={2012}, month={May}, pages={7978–7982} } @article{desimone_2012, title={Interview: From traditional polymer science to nanomedicine: the interplay between disciplines to drive innovation}, volume={7}, ISSN={1743-5889 1748-6963}, url={http://dx.doi.org/10.2217/nnm.12.89}, DOI={10.2217/nnm.12.89}, abstractNote={ Professor Joseph DeSimone speaks to Hannah Stanwix, Assistant Commissioning Editor Professor Joseph DeSimone attended Ursinus College (PA, USA) where he received his Bachelor of Science Degree in Chemistry. He completed his PhD in Chemistry in 1990 at Virginia Polytechnic Institute and State University (VA, USA). Professor DeSimone moved to the University of North Carolina at Chapel Hill (UNC-CH; NC, USA) where he was Assistant Professor of Chemistry until 1994. He was appointed Mary Ann Smith Professor of Chemistry at UNC-CH and Professor of Chemical Engineering at North Carolina State University (NC, USA) in 1995 and subsequently became William R Kenan Jr Distinguished Professor of Chemistry at UNC-CH in 1999. He is currently the Chancellor’s Eminent Professor of Chemistry at UNC-CH and the William R. Kenan Jr Distinguished Professor of Chemical Engineering at NC State. In 2004, Professor DeSimone founded Liquidia Technologies (NC, USA) which received the first ever equity investment by the Bill and Melinda Gates Foundation in a for-profit biotechnology company. He has received over 50 awards and accolades throughout his career, including the 2008 Lemelson-MIT Prize. Professor DeSimone has authored over 290 papers, as well as issuing 130 patents. }, number={8}, journal={Nanomedicine}, publisher={Future Medicine Ltd}, author={DeSimone, Joseph}, year={2012}, month={Aug}, pages={1125–1128} } @article{chen_merkel_pandya_napier_luft_daniel_sheiko_desimone_2012, title={Low Modulus Biomimetic Microgel Particles with High Loading of Hemoglobin}, volume={13}, ISSN={["1526-4602"]}, DOI={10.1021/bm3007242}, abstractNote={We synthesized extremely deformable red blood cell-like microgel particles and loaded them with bovine hemoglobin (Hb) to potentiate oxygen transport. With similar shape and size as red blood cells (RBCs), the particles were fabricated using the PRINT (particle replication in nonwetting templates) technique. Low cross-linking of the hydrogel resulted in very low mesh density for these particles, allowing passive diffusion of hemoglobin throughout the particles. Hb was secured in the particles through covalent conjugation of the lysine groups of Hb to carboxyl groups in the particles via EDC/NHS coupling. Confocal microscopy of particles bound to fluorescent dye-labeled Hb confirmed the uniform distribution of Hb throughout the particle interior, as opposed to the surface conjugation only. High loading ratios, up to 5 times the amount of Hb to polymer by weight, were obtained without a significant effect on particle stability and shape, though particle diameter decreased slightly with Hb conjugation. Analysis of the protein by circular dichroism (CD) spectroscopy showed that the secondary structure of Hb was unperturbed by conjugation to the particles. Methemoglobin in the particles could be maintained at a low level and the loaded Hb could still bind oxygen, as studied by UV-vis spectroscopy. Hb-loaded particles with moderate loading ratios demonstrated excellent deformability in microfluidic devices, easily deforming to pass through restricted pores half as wide as the diameter of the particles. The suspension of concentrated particles with a Hb concentration of 5.2 g/dL showed comparable viscosity to that of mouse blood, and the particles remained intact even after being sheared at a constant high rate (1000 1/s) for 10 min. Armed with the ability to control size, shape, deformability, and loading of Hb into RBC mimics, we will discuss the implications for artificial blood.}, number={9}, journal={BIOMACROMOLECULES}, author={Chen, Kai and Merkel, Timothy J. and Pandya, Ashish and Napier, Mary E. and Luft, J. Christopher and Daniel, Will and Sheiko, Sergei and DeSimone, Joseph M.}, year={2012}, month={Sep}, pages={2748–2759} } @article{perry_reuter_kai_herlihy_jones_luft_napier_bear_desimone_2012, title={PEGylated PRINT Nanoparticles: The Impact of PEG Density on Protein Binding, Macrophage Association, Biodistribution, and Pharmacokinetics}, volume={12}, ISSN={["1530-6992"]}, DOI={10.1021/nl302638g}, abstractNote={In this account, we varied PEGylation density on the surface of hydrogel PRINT nanoparticles and systematically observed the effects on protein adsorption, macrophage uptake, and circulation time. Interestingly, the density of PEGylation necessary to promote a long-circulating particle was dramatically less than what has been previously reported. Overall, our methodology provides a rapid screening technique to predict particle behavior in vivo and our results deliver further insight to what PEG density is necessary to facilitate long-circulation.}, number={10}, journal={NANO LETTERS}, author={Perry, Jillian L. and Reuter, Kevin G. and Kai, Marc P. and Herlihy, Kevin P. and Jones, Stephen W. and Luft, J. Chris and Napier, Mary and Bear, James E. and DeSimone, Joseph M.}, year={2012}, month={Oct}, pages={5304–5310} } @article{dunn_tian_blake_wang_galloway_murphy_pohlhaus_rolland_napier_desimone_2012, title={Reductively Responsive siRNA-Conjugated Hydrogel Nanoparticles for Gene Silencing}, volume={134}, ISSN={["1520-5126"]}, DOI={10.1021/ja300174v}, abstractNote={A critical need still remains for effective delivery of RNA interference (RNAi) therapeutics to target tissues and cells. Self-assembled lipid- and polymer-based systems have been most extensively explored for transfection with small interfering RNA (siRNA) in liver and cancer therapies. Safety and compatibility of materials implemented in delivery systems must be ensured to maximize therapeutic indices. Hydrogel nanoparticles of defined dimensions and compositions, prepared via a particle molding process that is a unique off-shoot of soft lithography known as particle replication in nonwetting templates (PRINT), were explored in these studies as delivery vectors. Initially, siRNA was encapsulated in particles through electrostatic association and physical entrapment. Dose-dependent gene silencing was elicited by PEGylated hydrogels at low siRNA doses without cytotoxicity. To prevent disassociation of cargo from particles after systemic administration or during postfabrication processing for surface functionalization, a polymerizable siRNA pro-drug conjugate with a degradable, disulfide linkage was prepared. Triggered release of siRNA from the pro-drug hydrogels was observed under a reducing environment while cargo retention and integrity were maintained under physiological conditions. Gene silencing efficiency and cytocompatibility were optimized by screening the amine content of the particles. When appropriate control siRNA cargos were loaded into hydrogels, gene knockdown was only encountered for hydrogels containing releasable, target-specific siRNAs, accompanied by minimal cell death. Further investigation into shape, size, and surface decoration of siRNA-conjugated hydrogels should enable efficacious targeted in vivo RNAi therapies.}, number={17}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Dunn, Stuart S. and Tian, Shaomin and Blake, Steven and Wang, Jin and Galloway, Ashley L. and Murphy, Andrew and Pohlhaus, Patrick D. and Rolland, Jason P. and Napier, Mary E. and DeSimone, Joseph M.}, year={2012}, month={May}, pages={7423–7430} } @article{xu_wang_luft_tian_owens_pandya_bergund_pohlhaus_maynor_smith_et al._2012, title={Rendering Protein-Based Particles Transiently Insoluble for Therapeutic Applications}, volume={134}, ISSN={["0002-7863"]}, DOI={10.1021/ja302363r}, abstractNote={Herein, we report the fabrication of protein (bovine serum albumin, BSA) particles which were rendered transiently insoluble using a novel, reductively labile disulfide-based cross-linker. After being cross-linked, the protein particles retain their integrity in aqueous solution and dissolve preferentially under a reducing environment. Our data demonstrates that cleavage of the cross-linker leaves no chemical residue on the reactive amino group. Delivery of a self-replicating RNA was achieved via the transiently insoluble PRINT protein particles. These protein particles can provide new opportunities for drug and gene delivery.}, number={21}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Xu, Jing and Wang, Jin J. and Luft, J. Christopher and Tian, Shaomin and Owens, Gary, Jr. and Pandya, Ashish A. and Bergund, Peter and Pohlhaus, Patrick and Maynor, Benjamin W. and Smith, Jonathan and et al.}, year={2012}, month={May}, pages={8774–8777} } @article{merkel_chen_jones_pandya_tian_napier_zamboni_desimone_2012, title={The effect of particle size on the biodistribution of low-modulus hydrogel PRINT particles}, volume={162}, ISSN={0168-3659}, url={http://dx.doi.org/10.1016/j.jconrel.2012.06.009}, DOI={10.1016/j.jconrel.2012.06.009}, abstractNote={There is a growing recognition that the deformability of particles used for drug delivery plays a significant role on their biodistribution and circulation profile. Understanding these effects would provide a crucial tool for the rational design of drug delivery systems. While particles resembling red blood cells (RBCs) in size, shape and deformability have extended circulation times and altered biodistribution profiles compared to rigid, but otherwise similar particles, the in vivo behavior of such highly deformable particles of varied size has not been explored. We report the fabrication of a series of discoid, monodisperse, low-modulus hydrogel particles with diameters ranging from 0.8 to 8.9 μm, spanning sizes smaller than and larger than RBCs. We injected these particles into healthy mice, and tracked their concentration in the blood and their distribution into major organs. These deformable particles all demonstrated some hold up in filtration tissues like the lungs and spleen, followed by release back into the circulation, characterized by decreases in particles in these tissues with concomitant increases in particle concentration in blood. Particles similar to red blood cells in size demonstrated longer circulation times, suggesting that this size and shape of deformable particle is uniquely suited to avoid clearance.}, number={1}, journal={Journal of Controlled Release}, publisher={Elsevier BV}, author={Merkel, Timothy J. and Chen, Kai and Jones, Stephen W. and Pandya, Ashish A. and Tian, Shaomin and Napier, Mary E. and Zamboni, William E. and DeSimone, Joseph M.}, year={2012}, month={Aug}, pages={37–44} } @article{wang_finlay_betts_merkel_luft_callow_callow_desimone_2011, title={Amphiphilic Co-networks with Moisture-Induced Surface Segregation for High-Performance Nonfouling Coatings}, volume={27}, ISSN={["0743-7463"]}, DOI={10.1021/la202427z}, abstractNote={Herein we report the design of a photocurable amphiphilic co-network consisting of perfluoropolyether and poly(ethylene glycol) segments that display outstanding nonfouling characteristics with respect to spores of green fouling alga Ulva when cured under high humidity conditions. The analysis of contact angle hysteresis revealed that the poly(ethylene glycol) density at the surface was enhanced when cured under high humidity. The nonfouling behavior of nonbiocidal surfaces against marine fouling is rare because such surfaces usually reduce the adhesion of organisms rather than inhibit colonization. We propose that the resultant surface segregation of these materials induced by high humidity may be a promising strategy for achieving nonfouling materials, and such an approach is more important than simply concentrating poly(ethylene glycol) moieties at an interface because the low surface energy has been maintained in our work.}, number={17}, journal={LANGMUIR}, author={Wang, Yapei and Finlay, John A. and Betts, Douglas E. and Merkel, Timothy J. and Luft, J. Christopher and Callow, Maureen E. and Callow, James A. and DeSimone, Joseph M.}, year={2011}, month={Sep}, pages={10365–10369} } @article{ko_tumbleston_henderson_euliss_desimone_lopez_samulski_2011, title={Biomimetic microlens array with antireflective “moth-eye” surface}, volume={7}, ISSN={1744-683X 1744-6848}, url={http://dx.doi.org/10.1039/c1sm05302g}, DOI={10.1039/c1sm05302g}, abstractNote={We report a replication route to non-planar, three dimensional microlens arrays with an antireflective surface nanopattern. Our methodology uses the surface topography of the Attacus atlas moth's compound eye and a soft lithographic technique to fabricate topographically faithful moulds that, in turn, are used to reproducibly replicate the original eye surface with nanoscale fidelity. In addition to antireflection, the resulting poly(urethane) replica with its “moth-eye” nanopattern also exhibits increased hydrophobicity relative to the unpatterned polymer. The materials flexibility of the perfluoropolyether mould fabricated viareplica moulding enables, for example, the embossing of antireflective nanopatterns in the photoactive materials of organic solar cells.}, number={14}, journal={Soft Matter}, publisher={Royal Society of Chemistry (RSC)}, author={Ko, Doo-Hyun and Tumbleston, John R. and Henderson, Kevin J. and Euliss, Larken E. and DeSimone, Joseph M. and Lopez, Rene and Samulski, Edward T.}, year={2011}, pages={6404} } @article{hasan_chu_gullapalli_dunn_enlow_luft_tian_napier_pohlhaus_rolland_et al._2012, title={Delivery of Multiple siRNAs Using Lipid-Coated PLGA Nanoparticles for Treatment of Prostate Cancer}, volume={12}, ISSN={["1530-6992"]}, DOI={10.1021/nl2035354}, abstractNote={Nanotechnology can provide a critical advantage in developing strategies for cancer management and treatment by helping to improve the safety and efficacy of novel therapeutic delivery vehicles. This paper reports the fabrication of poly(lactic acid-co-glycolic acid)/siRNA nanoparticles coated with lipids for use as prostate cancer therapeutics made via a unique soft lithography particle molding process called Particle Replication In Nonwetting Templates (PRINT). The PRINT process enables high encapsulation efficiency of siRNA into neutral and monodisperse PLGA particles (32-46% encapsulation efficiency). Lipid-coated PLGA/siRNA PRINT particles were used to deliver therapeutic siRNA in vitro to knockdown genes relevant to prostate cancer.}, number={1}, journal={NANO LETTERS}, author={Hasan, Warefta and Chu, Kevin and Gullapalli, Anuradha and Dunn, Stuart S. and Enlow, Elizabeth M. and Luft, J. Christopher and Tian, Shaomin and Napier, Mary E. and Pohlhaus, Patrick D. and Rolland, Jason P. and et al.}, year={2012}, month={Jan}, pages={287–292} } @article{merkel_desimone_2011, title={Dodging Drug-Resistant Cancer with Diamonds}, volume={3}, ISSN={["1946-6242"]}, DOI={10.1126/scitranslmed.3002137}, abstractNote={Nanodiamond-drug conjugates show antitumor activity in mouse models of chemoresistant breast and liver cancer.}, number={73}, journal={SCIENCE TRANSLATIONAL MEDICINE}, author={Merkel, Timothy J. and DeSimone, Joseph M.}, year={2011}, month={Mar} } @article{benhabbour_luft_kim_jain_wadhwa_parrott_liu_desimone_mumper_2012, title={In vitro and in vivo assessment of targeting lipid-based nanoparticles to the epidermal growth factor-receptor (EGFR) using a novel Heptameric ZEGFR domain}, volume={158}, ISSN={0168-3659}, url={http://dx.doi.org/10.1016/j.jconrel.2011.10.013}, DOI={10.1016/j.jconrel.2011.10.013}, abstractNote={Lipid-based oil-filled nanoparticles (NPs) with a high concentration of surface-chelated nickel (Ni-NPs) were successfully prepared using a Brij 78-NTA-Ni conjugate synthesized with Brij 78 (Polyoxyethylene (20) stearyl ether) and nitrilotriacetic acid (NTA). The facile incorporation of the Brij 78-NTA-Ni conjugate into the NP formulation allowed up to 90% Ni incorporation, which was a significant improvement over the previously used standard agent DOGS-NTA-Ni which led to ~ 6% Ni incorporation. The Ni-NPs were targeted to the highly epidermal growth factor receptor (EGFR)-overexpressing epidermoid carcinoma cells A431. This was accomplished using a novel high affinity histidine × 6-tagged EGFR-binding Z domain (heptameric ZEGFR domain). In vitro cell uptake studies showed enhanced internalization (up to 90%) of the targeted Ni-NPs in A431 cells with only ≤ 10% internalization of the untargeted Ni-NPs. ICP-MS analysis used to quantify the amount of Ni in the cells were in close agreement with flow cytometry studies, which showed a dose dependent increase in the amount of Ni with the targeted Ni-NPs. Cell uptake competition studies showed that internalization of the targeted Ni-NPs within the cells was competed off with free heptameric ZEGFR domain at concentrations of 8.75 ng/mL or higher. In vivo studies were carried out in nude mice bearing A431 tumors to determine the biodistribution and intracellular delivery. Near Infrared (NIR) optical imaging studies using Alexa750-labeled heptameric ZEGFR domain showed localization of 19% of the total detected fluorescence intensity in the tumor tissue, 28% in the liver and 42% in the kidneys 16 h post i.v. injection. ICP-MS analysis showed almost a two-fold increase in the amount of intracellular Ni with the targeted Ni-NPs. These new Ni-NPs could be a very useful tool for targeting and drug delivery to a wide range of EGFR positive cancers.}, number={1}, journal={Journal of Controlled Release}, publisher={Elsevier BV}, author={Benhabbour, S. Rahima and Luft, J. Christopher and Kim, Dongwook and Jain, Anekant and Wadhwa, Saurabh and Parrott, Matthew C. and Liu, Rihe and DeSimone, Joseph M. and Mumper, Russell J.}, year={2012}, month={Feb}, pages={63–71} } @article{wang_pitet_finlay_brewer_cone_betts_callow_callow_wendt_hillmyer_et al._2011, title={Investigation of the role of hydrophilic chain length in amphiphilic perfluoropolyether/poly(ethylene glycol) networks: towards high-performance antifouling coatings}, volume={27}, ISSN={0892-7014 1029-2454}, url={http://dx.doi.org/10.1080/08927014.2011.629344}, DOI={10.1080/08927014.2011.629344}, abstractNote={The facile preparation of amphiphilic network coatings having a hydrophobic dimethacryloxy-functionalized perfluoropolyether (PFPE-DMA; M w = 1500 g mol−1) crosslinked with hydrophilic monomethacryloxy functionalized poly(ethylene glycol) macromonomers (PEG-MA; M w = 300, 475, 1100 g mol−1), intended as non-toxic high-performance marine coatings exhibiting antifouling characteristics is demonstrated. The PFPE-DMA was found to be miscible with the PEG-MA. Photo-cured blends of these materials containing 10 wt% of PEG-MA oligomers did not swell significantly in water. PFPE-DMA crosslinked with the highest molecular weight PEG oligomer (ie PEG1100) deterred settlement (attachment) of algal cells and cypris larvae of barnacles compared to a PFPE control coating. Dynamic mechanical analysis of these networks revealed a flexible material. Preferential segregation of the PEG segments at the polymer/air interface resulted in enhanced antifouling performance. The cured amphiphilic PFPE/PEG films showed decreased advancing and receding contact angles with increasing PEG chain length. In particular, the PFPE/PEG1100 network had a much lower advancing contact angle than static contact angle, suggesting that the PEG1100 segments diffuse to the polymer/water interface quickly. The preferential interfacial aggregation of the larger PEG segments enables the coating surface to have a substantially enhanced resistance to settlement of spores of the green seaweed Ulva, cells of the diatom Navicula and cypris larvae of the barnacle Balanus amphitrite as well as low adhesion of sporelings (young plants) of Ulva, adhesion being lower than to a polydimethyl elastomer, Silastic T2.}, number={10}, journal={Biofouling}, publisher={Informa UK Limited}, author={Wang, Yapei and Pitet, Louis M. and Finlay, John A. and Brewer, Lenora H. and Cone, Gemma and Betts, Douglas E. and Callow, Maureen E. and Callow, James A. and Wendt, Dean E. and Hillmyer, Marc A. and et al.}, year={2011}, month={Nov}, pages={1139–1150} } @misc{wang_byrne_napier_desimone_2011, title={More Effective Nanomedicines through Particle Design}, volume={7}, ISSN={["1613-6829"]}, DOI={10.1002/smll.201100442}, abstractNote={AbstractNanomedicine is an emerging field that applies concepts in nanotechnology to develop novel diagnostics and therapies. Physical and chemical properties of particles, including size, shape, modulus, surface charge and surface chemistry, play an important role in determining particle–cell interactions, cellular trafficking mechanisms, biodistribution, and pharmacokinetics. This discussion focuses on both nanoparticles and microparticles since microparticles can also provide many insights for the development of drug carriers and possess advantages over nanoparticles in certain applications. This review covers recent major advancement in the nanomedicine field and also highlights studies using the PRINT technology.}, number={14}, journal={SMALL}, author={Wang, Jin and Byrne, James D. and Napier, Mary E. and DeSimone, Joseph M.}, year={2011}, month={Jul}, pages={1919–1931} } @misc{pillai_dunn_napier_desimone_2011, title={Novel Platforms for Vascular Carriers with Controlled Geometry}, volume={63}, ISSN={["1521-6551"]}, DOI={10.1002/iub.497}, abstractNote={AbstractThe first‐generation platforms for vascular drug delivery adopted spherical morphologies. These carriers relied primarily on the size dependence of the enhanced permeability and retention effect to passively target vasculature, resulting in inefficient delivery due to significant variation in endothelial permeability. Enhanced delivery typically requires active targeting via receptor‐mediated endocytosis by surface conjugation of targeting ligands. However, vascular carriers (VCs) still face numerous challenges en route to reaching their targets before delivery. The control of carrier shape offers opportunities to overcome in vivo barriers and enhance vascular drug delivery. Geometric features influence the ability of carrier particles to navigate physiological flow patterns, evade biological clearance mechanisms, sustain circulation, adhere to the vascular surface, and finally transport across or internalize into the endothelium. Although previous formulation strategies limited the fabrication of nonspherical carriers, numerous recent advances in both top‐down and bottom‐up fabrication techniques have enabled shape modulation as a key design element. As part of a series on vascular drug delivery, this review focuses on recent developments in novel vascular platforms with controlled geometry that enhance or modulate delivery functions. Starting with an overview of controlled geometry platforms, we review their shape‐dependent functional characteristics for each stage of their vascular journey in vivo. We sequentially explore carrier geometries that evade reticuloendothelial system uptake, display enhanced circulation persistence and margination dynamics in flow, encourage adhesion to the vascular surface or extravasation through endothelium, and impact extravascular transport and cell internalization. The eventual biodistribution of VCs results from the culmination of their successive navigation of all these barriers and is profoundly influenced by their morphology. To enhance delivery efficacy, carrier designs synergistically combining controlled geometry with standard drug delivery strategies such as targeting moieties, surface decorations, and bulk material properties are discussed. Finally, we speculate on possibilities for innovation, harnessing shape as a design parameter for the next generation of vascular drug delivery platforms. © 2011 IUBMB IUBMB Life, 2011}, number={8}, journal={IUBMB LIFE}, author={Pillai, Jonathan D. and Dunn, Stuart S. and Napier, Mary E. and DeSimone, Joseph M.}, year={2011}, month={Aug}, pages={596–606} } @article{perry_herlihy_napier_desimone_2011, title={PRINT: A Novel Platform Toward Shape and Size Specific Nanoparticle Theranostics}, volume={44}, ISSN={0001-4842 1520-4898}, url={http://dx.doi.org/10.1021/ar2000315}, DOI={10.1021/ar2000315}, abstractNote={Nanotheranostics represents the next generation of medicine, fusing nanotechnology, therapeutics, and diagnostics. By integrating therapeutic and imaging agents into one nanoparticle, this new treatment strategy has the potential not only to detect and diagnose disease but also to treat and monitor the therapeutic response. This capability could have a profound impact in both the research setting as well as in a clinical setting. In the research setting, such a capability will allow research scientists to rapidly assess the performance of new therapeutics in an effort to iterate their designs for increased therapeutic index and efficacy. In the clinical setting, theranostics offers the ability to determine whether patients enrolling in clinical trials are responding, or are expected to respond, to a given therapy based on the hypothesis associated with the biological mechanisms being tested. If not, patients can be more quickly removed from the clinical trial and shifted to other therapeutic options. To be effective, these theranostic agents must be highly site specific. Optimally, they will carry relevant cargo, demonstrate controlled release of that cargo, and include imaging probes with a high signal-to-noise ratio. There are many biological barriers in the human body that challenge the efficacy of nanoparticle delivery vehicles. These barriers include, but are not limited to, the walls of blood vessels, the physical entrapment of particles in organs, and the removal of particles by phagocytic cells. The rapid clearance of circulating particles during systemic delivery is a major challenge; current research seeks to define key design parameters that govern the performance of nanocarriers, such as size, surface chemistry, elasticity, and shape. The effect of particle size and surface chemistry on in vivo biodistribution of nanocarriers has been extensively studied, and general guidelines have been established. Recently it has been documented that shape and elasticity can have a profound effect on the behavior of delivery vehicles. Thus, having the ability to independently control shape, size, matrix, surface chemistry, and modulus is crucial for designing successful delivery agents. In this Account, we describe the use of particle replication in nonwetting templates (PRINT) to fabricate shape- and size-specific microparticles and nanoparticles. A particular strength of the PRINT method is that it affords precise control over shape, size, surface chemistry, and modulus. We have demonstrated the loading of PRINT particles with chemotherapeutics, magnetic resonance contrast agents, and fluorophores. The surface properties of the PRINT particles can be easily modified with "stealth" poly(ethylene glycol) chains to increase blood circulation time, with targeting moieties for targeted delivery or with radiolabels for nuclear imaging. These particles have tremendous potential for applications in nanomedicine and diagnostics.}, number={10}, journal={Accounts of Chemical Research}, publisher={American Chemical Society (ACS)}, author={Perry, Jillian L. and Herlihy, Kevin P. and Napier, Mary E. and DeSimone, Joseph M.}, year={2011}, month={Oct}, pages={990–998} } @article{wang_betts_finlay_brewer_callow_callow_wendt_desimone_2011, title={Photocurable Amphiphilic Perfluoropolyether/Poly(ethylene glycol) Networks for Fouling-Release Coatings}, volume={44}, ISSN={["1520-5835"]}, DOI={10.1021/ma102271t}, abstractNote={We demonstrate a facile way of cross-linking hydrophobic perfluoropolyethers, PFPEs, with a series of hydrophilic poly(ethylene glycol)s, PEGs, to prepare a range of amphiphilic networks for use as fouling-release coatings. The PFPE matrix of the networks endows the coating with a low surface energy while the PEG is added to weaken fouling adhesion. It is therefore envisioned that the coating surfaces of these optically transparent and mechanically robust films will display hydrophobicity leading to nonfouling and fouling release characteristics. Two kinds of functionalized PEG oligomers have been cross-linked with reactive, dimethacryloxy-functionalized PFPE oligomers to form a range of amphiphilic networks: (i) a monomethacryloxy-functionalized PEG macromonomer (454 g/mol) (PEG454−MA) which was used to yield blends with flexible PEG chains on the surface as well as in bulk and (ii) a dimethacryloxy-functionalized PEG (550 g/mol) (PEG550−DMA) which results in PEG chains that are relatively more restricte...}, number={4}, journal={MACROMOLECULES}, author={Wang, Yapei and Betts, Douglas E. and Finlay, John A. and Brewer, Lenora and Callow, Maureen E. and Callow, James A. and Wendt, Dean E. and DeSimone, Joseph M.}, year={2011}, month={Feb}, pages={878–885} } @article{enlow_luft_napier_desimone_2011, title={Potent Engineered PLGA Nanoparticles by Virtue of Exceptionally High Chemotherapeutic Loadings}, volume={11}, ISSN={["1530-6992"]}, DOI={10.1021/nl104117p}, abstractNote={Herein we report the fabrication of engineered poly(lactic acid-co-glycolic acid) nanoparticles via the PRINT (particle replication in nonwetting templates) process with high and efficient loadings of docetaxel, up to 40% (w/w) with encapsulation efficiencies >90%. The PRINT process enables independent control of particle properties leading to a higher degree of tailorability than traditional methods. Particles with 40% loading display better in vitro efficacy than particles with lower loadings and the clinical formulation of docetaxel, Taxotere.}, number={2}, journal={NANO LETTERS}, author={Enlow, Elizabeth M. and Luft, J. Christopher and Napier, Mary E. and DeSimone, Joseph M.}, year={2011}, month={Feb}, pages={808–813} } @article{parrott_desimone_2011, title={Relieving PEGylation}, volume={4}, ISSN={1755-4330 1755-4349}, url={http://dx.doi.org/10.1038/nchem.1230}, DOI={10.1038/nchem.1230}, abstractNote={A new type of protein–polymer conjugate provides improved stability without detrimentally affecting bioactivity, and thus offers great potential for the development of new peptide-based drugs.}, number={1}, journal={Nature Chemistry}, publisher={Springer Nature}, author={Parrott, Matthew C. and DeSimone, Joseph M.}, year={2011}, month={Dec}, pages={13–14} } @article{brown_zhang_forman_maynor_betts_desimone_jaeger_2011, title={Shear thickening and jamming in densely packed suspensions of different particle shapes}, volume={84}, ISSN={1539-3755 1550-2376}, url={http://dx.doi.org/10.1103/physreve.84.031408}, DOI={10.1103/physreve.84.031408}, abstractNote={We investigated the effects of particle shape on shear thickening in densely packed suspensions. Rods of different aspect ratios and nonconvex hooked rods were fabricated. Viscosity curves and normal stresses were measured using a rheometer for a wide range of packing fractions for each shape. Suspensions of each shape exhibit qualitatively similar discontinuous shear thickening. The logarithmic slope of the stress vs shear rate increases dramatically with packing fraction and diverges at a critical packing fraction φ(c) which depends on particle shape. The packing fraction dependence of the viscosity curves for different convex shapes can be collapsed when the packing fraction is normalized by φ(c). Intriguingly, viscosity curves for nonconvex particles do not collapse on the same set as convex particles, showing strong shear thickening over a wider range of packing fraction. The value of φ(c) is found to coincide with the onset of a yield stress at the jamming transition, suggesting the jamming transition also controls shear thickening. The yield stress is found to correspond with trapped air in the suspensions, and the scale of the stress can be attributed to interfacial tension forces which dramatically increase above φ(c) due to the geometric constraints of jamming. Using this connection we show that the jamming transition can be identified by simply looking at the surface of suspensions. The relationship between shear and normal stresses is found to be linear in both the shear thickening and jammed regimes, indicating that the shear stresses come from friction. In the limit of zero shear rate, normal stresses pull the rheometer plates together due to the surface tension of the liquid below φ(c), but push the rheometer plates apart due to jamming above φ(c).}, number={3}, journal={Physical Review E}, publisher={American Physical Society (APS)}, author={Brown, Eric and Zhang, Hanjun and Forman, Nicole A. and Maynor, Benjamin W. and Betts, Douglas E. and DeSimone, Joseph M. and Jaeger, Heinrich M.}, year={2011}, month={Sep} } @article{wang_wang_sheiko_betts_desimone_2012, title={Tuning Multiphase Amphiphilic Rods to Direct Self-Assembly}, volume={134}, ISSN={["0002-7863"]}, DOI={10.1021/ja2066187}, abstractNote={New methods to direct the self-assembly of particles are highly sought after for multiple applications, including photonics, electronics, and drug delivery. Most techniques, however, are limited to chemical patterning on spherical particles, limiting the range of possible structures. We developed a lithographic technique for fabrication of chemically anisotropic rod-like particles in which we can specify both the size and shape of particles and implement multiple diverse materials to control interfacial interactions. Multiphase rod-like particles, including amphiphilic diblock, triblock, and multiblock were fabricated in the same template mold having a tunable hydrophilic/hydrophobic ratio. Self-assembly of diblock or triblock rods at a water/oil interface led to the formation of bilayer or ribbon-like structures.}, number={13}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Wang, Jie-Yu and Wang, Yapei and Sheiko, Sergei S. and Betts, Douglas E. and DeSimone, Joseph M.}, year={2012}, month={Apr}, pages={5801–5806} } @article{merkel_jones_herlihy_kersey_shields_napier_luft_wu_zamboni_wang_et al._2011, title={Using mechanobiological mimicry of red blood cells to extend circulation times of hydrogel microparticles}, volume={108}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1010013108}, abstractNote={It has long been hypothesized that elastic modulus governs the biodistribution and circulation times of particles and cells in blood; however, this notion has never been rigorously tested. We synthesized hydrogel microparticles with tunable elasticity in the physiological range, which resemble red blood cells in size and shape, and tested their behavior in vivo. Decreasing the modulus of these particles altered their biodistribution properties, allowing them to bypass several organs, such as the lung, that entrapped their more rigid counterparts, resulting in increasingly longer circulation times well past those of conventional microparticles. An 8-fold decrease in hydrogel modulus correlated to a greater than 30-fold increase in the elimination phase half-life for these particles. These results demonstrate a critical design parameter for hydrogel microparticles.}, number={2}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Merkel, Timothy J. and Jones, Stephen W. and Herlihy, Kevin P. and Kersey, Farrell R. and Shields, Adam R. and Napier, Mary and Luft, J. Christopher and Wu, Huali and Zamboni, William C. and Wang, Andrew Z. and et al.}, year={2011}, month={Jan}, pages={586–591} } @misc{jeong_napier_desimone_2010, title={Challenging nature's monopoly on the creation of well-defined nanoparticles}, volume={5}, ISSN={["1748-6963"]}, DOI={10.2217/nnm.10.34}, abstractNote={ Nature has selected and fine-tuned the physical and chemical properties of natural objects, such as size, shape, mechanical properties and surface chemistry, at the molecular level in order to modulate biological functions. A new particle fabrication process, particle replication in nonwetting templates (PRINT®), has recently begun to attempt to emulate nature’s ability to control those physical and chemical traits. The PRINT technology, which combines modern soft lithography with the unique properties of perfluoropolyether molds, enables the production of nanoparticles with unprecedented control of size, shape, chemical composition, deformability and surface functionality. This scalable ‘top-down’ fabrication process allows for the generation of well-defined nanostructures without the need for molecular assembly. The ability to flexibly engineer various matrix materials offers unique opportunities for the development of nanomedicines with desired functionality. The strength and versatility of PRINT makes it a powerful platform in nanomedicine for elucidating the role of physical and chemical properties of nanodelivery vehicles on the behavior and fate at the cellular, tissue and whole organism level. Utilizing the PRINT technology, we are generating well-defined nanomedicines with tailored properties for preclinical studies against a variety of human diseases. }, number={4}, journal={NANOMEDICINE}, author={Jeong, Wonhee and Napier, Mary E. and DeSimone, Joseph M.}, year={2010}, month={Jun}, pages={633–639} } @article{ahmed_desimone_roberts_2010, title={Continuous precipitation polymerization of vinylidene fluoride in supercritical carbon dioxide: A model for understanding the molecular-weight distribution}, volume={65}, ISSN={["1873-4405"]}, DOI={10.1016/j.ces.2009.08.039}, abstractNote={Abstract Poly(vinylidene fluoride) (PVDF) that is synthesized by precipitation polymerization in supercritical carbon dioxide (scCO2) has a bimodal molecular weight distribution (MWD) and a very broad polydispersity index (PDI) under certain reaction conditions. Different models have been formulated to account for this behavior. This paper presents a homogenous model for a continuous stirred-tank reactor (CSTR) that includes the change of the termination reaction from kinetic control to diffusion control as the chain length of the polymeric radicals increases, and accounts for the change in the termination rate constant with macroradical chain length in the diffusion-controlled region. The model also includes the chain transfer to polymer reaction. Comparison of the model output with experimental data demonstrates that changes of the MWD, including the development of a bimodal distribution, with such reaction conditions as monomer concentration and average residence time are successfully predicted. In addition, the model can capture the occurrence of gelation, which appears to be responsible for a region of inoperability that was observed in the polymerization experiments. The success of this homogeneous model is consistent with recent research demonstrating that the CO2-rich phase is the main locus of polymerization for the precipitation polymerization of vinylidene fluoride and vinylidene fluoride/hexafluoropropylene mixtures in scCO2, at the conditions that have been studied to date.}, number={2}, journal={CHEMICAL ENGINEERING SCIENCE}, author={Ahmed, Tamer S. and DeSimone, Joseph M. and Roberts, George W.}, year={2010}, month={Jan}, pages={651–659} } @article{hampton_templeton_desimone_2010, title={Direct Patterning of CdSe Quantum Dots into Sub-100 nm Structures}, volume={26}, ISSN={["0743-7463"]}, DOI={10.1021/la904787k}, abstractNote={Ordered, two-dimensional cadmium selenide (CdSe) arrays have been fabricated on indium-doped tin oxide (ITO) electrodes using the pattern replication in nonwetting templates (PRINT) process. CdSe quantum dots (QDs) with an average diameter of 2.7 nm and a pyridine surface ligand were used for patterning. The PRINT technique utilizes a perfluoropolyether (PFPE) elastomeric mold that is tolerant of most organic solvents, thus allowing solutions of CdSe QDs in 4-picoline to be used for patterning without significant deformation of the mold. Nanometer-scale diffraction gratings have been successfully replicated with CdSe QDs.}, number={5}, journal={LANGMUIR}, author={Hampton, Meredith J. and Templeton, Joseph L. and DeSimone, Joseph M.}, year={2010}, month={Mar}, pages={3012–3015} } @article{brown_forman_orellana_zhang_maynor_betts_desimone_jaeger_2010, title={Generality of shear thickening in dense suspensions}, volume={9}, ISSN={1476-1122 1476-4660}, url={http://dx.doi.org/10.1038/nmat2627}, DOI={10.1038/nmat2627}, abstractNote={Suspensions are of wide interest and form the basis for many smart fluids. For most suspensions, the viscosity decreases with increasing shear rate, that is, they shear thin. Few are reported to do the opposite, that is, shear thicken, despite the longstanding expectation that shear thickening is a generic type of suspension behaviour. Here we resolve this apparent contradiction. We demonstrate that shear thickening can be masked by a yield stress and can be recovered when the yield stress is decreased below a threshold. We show the generality of this argument and quantify the threshold in rheology experiments where we control yield stresses arising from a variety of sources, such as attractions from particle surface interactions, induced dipoles from applied electric and magnetic fields, as well as confinement of hard particles at high packing fractions. These findings open up possibilities for the design of smart suspensions that combine shear thickening with electro- or magnetorheological response.}, number={3}, journal={Nature Materials}, publisher={Springer Science and Business Media LLC}, author={Brown, Eric and Forman, Nicole A. and Orellana, Carlos S. and Zhang, Hanjun and Maynor, Benjamin W. and Betts, Douglas E. and DeSimone, Joseph M. and Jaeger, Heinrich M.}, year={2010}, month={Jan}, pages={220–224} } @article{wang_merkel_chen_fromen_betts_desimone_2011, title={Generation of a Library of Particles Having Controlled Sizes and Shapes via the Mechanical Elongation of Master Templates}, volume={27}, ISSN={["0743-7463"]}, DOI={10.1021/la1045095}, abstractNote={Herein we describe a versatile and readily scalable approach for the fabrication of particles with a variety of shapes and sizes from a single master template by augmenting the particle replication in nonwetting templates (PRINT) method with mechanical elongation. Repetition of the elongation steps in one direction leads to the fabrication of linear particles with high aspect ratio (AR), over 40 times greater than in the original master, while a range of particle shapes can be obtained by repeating the elongation procedure while changing the stretching direction, generating diamond, rectangular, curved parallelogram particles from a single cubic master.}, number={2}, journal={LANGMUIR}, author={Wang, Yapei and Merkel, Timothy J. and Chen, Kai and Fromen, Catherine Ann and Betts, Douglas E. and DeSimone, Joseph M.}, year={2011}, month={Jan}, pages={524–528} } @article{nunes_ertas_du_desimone_2010, title={Hierarchical Control of Polymer Composite Nano- and Micro-Structure with Lithography}, volume={22}, ISSN={["1520-5002"]}, DOI={10.1021/cm100931r}, abstractNote={We have developed a novel composite film fabrication process that utilizes the soft lithographic approach, Particle Replication in Nonwetting Templates (PRINT). This process was found to be a very viable approach to the fabrication of well-structured, multifunctional polymer composite thin films. Particle aggregation was completely eliminated as discretely molded particles with specific shape, size and composition were maintained in well-defined arrays determined by the silicon master template. Both all-organic and polymer-ceramic composites have been generated using this technique with particle inclusions ranging in size from 200 nm to 20 μm. The composition of the composite was well-controlled with both cross-linked and thermoplastic polymeric continuous phases, as well as particle compositions ranging from cross-linked polymeric resins to the inorganic oxide, barium titanate.}, number={13}, journal={CHEMISTRY OF MATERIALS}, author={Nunes, Janine K. and Ertas, Merve and Du, Libin and DeSimone, Joseph M.}, year={2010}, month={Jul}, pages={4069–4075} } @article{hu_pitet_hillmyer_desimone_2010, title={High Modulus, Low Surface Energy, Photochemically Cured Materials from Liquid Precursors}, volume={43}, ISSN={["1520-5835"]}, DOI={10.1021/ma101180k}, abstractNote={A new strategy has been developed to achieve durable, low surface tension fluorinated polymeric materials by copolymerizing a tetramethacryloxy-modified perfluoropolyether (PFPE) macro- monomer and a fluorinated difunctional cross-linker, 1H,1H,6H,6H-perfluoro-1,6-hexyl diacrylate (PFHDA), into very highly cross-linked materials that possess a very high modulus as well as a very low surface energy. The miscibility of the two fluorinated components has been studied by measuring the cloud- point temperatures. Partially miscible mixtures yielded optically transparent samples after curing at low PFHDA contents (e.g., <40 wt %), and cloudy samples were obtained at high PFHDA contents when cured at room temperature. However, it was possible to achieve optically transparent samples with high PFHDA contents by increasing the cure temperature. The miscibility of these materials has been further studied by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and atomic force microscopy (AFM). By incorporating PFHDA into the cross-linked system, a low surface energy, very high modulus(upto458MPa)thermosetcould beachieved whichis importantformanyapplicationsincludingas hard, abrasion-resistant coating materials.}, number={24}, journal={MACROMOLECULES}, author={Hu, Zhaokang and Pitet, Louis M. and Hillmyer, Marc A. and DeSimone, Joseph M.}, year={2010}, month={Dec}, pages={10397–10405} } @article{williams_retterer_lopez_ruiz_samulski_desimone_2010, title={High-Resolution PFPE-based Molding Techniques for Nanofabrication of High-Pattern Density, Sub-20 nm Features: A Fundamental Materials Approach}, volume={10}, ISSN={["1530-6992"]}, DOI={10.1021/nl100326q}, abstractNote={Several perfluoropolyether (PFPE)-based elastomers for high-resolution replica molding applications are explored. The modulus of the elastomeric materials was increased through synthetic and additive approaches while maintaining relatively low surface tension values (<25 mN/m). Using large area (>4 in.(2)) master templates, we experimentally show the relationship between mold resolution and material properties such as modulus and surface tension for materials used in this study. A composite mold approach was used to form flexible molds out of stiff, high modulus materials that allow for replication of sub-20 nm post structures. Sub-100 nm line grating master templates, formed using e-beam lithography, were used to determine the experimental stability of the molding materials. It was observed that as the feature spacing decreased, high modulus PFPE tetramethacrylate (TMA) composite molds were able to effectively replicate the nanograting structures without cracking or tear-out defects that typically occur with high modulus elastomers.}, number={4}, journal={NANO LETTERS}, author={Williams, Stuart S. and Retterer, Scott and Lopez, Rene and Ruiz, Ricardo and Samulski, Edward T. and DeSimone, Joseph M.}, year={2010}, month={Apr}, pages={1421–1428} } @article{knight_goldstein_brennaman_cardolaccia_pandya_desimone_meyer_2011, title={Influence of the Fluid-to-Film Transition on Photophysical Properties of MLCT Excited States in a Polymerizable Dimethacrylate Fluid}, volume={115}, ISSN={1520-6106 1520-5207}, url={http://dx.doi.org/10.1021/jp107077t}, DOI={10.1021/jp107077t}, abstractNote={Photophysical properties of the salts [Ru(bpy)(3)](p-Tos)(2), [Ru(dmb)(3)](PF(6))(2), [Ru(vbpy)(3)](PF(6))(2), and [Ru(phen)(3)](p-Tos)(2) (bpy = 2,2'-bipyridine, dmb = 4,4'-dimethyl-2,2'-bipyridine, vbpy = 4-methyl-4'-vinyl-2,2'-bipyridine, phen = 1,10-phenanthroline, and p-Tos = p-toluene sulfonate) in fluid and film polyethylene glycol dimethacrylate containing nine ethylene glycol spacers (PEG-DMA550) are reported. MLCT absorption energies and bandshapes are similar in fluid and film PEG-DMA550 pointing to similar local dielectric environments, presumably dominated by the polar acrylate groups. Emission energies and excited-to-ground state 0-0 energy gaps (E(0)), determined by emission spectral fitting, are blue-shifted, and band-widths-at-half height (Δv(0,1/2)) decreased, due to an expected "rigid medium effect" in PEG-DMA550 film. The extent of loss of medium dipole reorientation in the rigid environment, and the increased emission energies in the film, resulted in enhanced emission quantum yields and excited state lifetimes in accordance with the energy gap law. The "rigid medium effect" in PEG-DMA550 is less pronounced than in films of poly(methyl methacrylate) (PMMA) pointing to a more fluid-like local environment presumably arising from the ethylene glycol linker spacers in PEG-DMA550. Comparison of the absorption, emission, emission spectral fitting, and emission lifetime results for [Ru(dmb)(3)](PF(6))(2) and [Ru(vbpy)(3)](PF(6))(2) shows that the vinyl groups of vbpy copolymerize with PEG-DMA550 covalently incorporating Ru(vbpy)(3)(2+) as a cross-linker into the polymer network. The most dramatic effect of the fluid-to-film transition is seen in the emission lifetime data for [Ru(phen)(3)](p-Tos)(2), with an increase of ~3 in the PEG-DMA550 film. Ru(phen)(3)(2+) cations appear to occupy a low symmetry site in the films probably close to the polar acrylate groups in a structurally confined environment.}, number={1}, journal={The Journal of Physical Chemistry B}, publisher={American Chemical Society (ACS)}, author={Knight, Troy E. and Goldstein, Anna P. and Brennaman, M. Kyle and Cardolaccia, Thomas and Pandya, Ashish and DeSimone, Joseph M. and Meyer, Thomas J.}, year={2011}, month={Jan}, pages={64–70} } @article{juliano_sunnarborg_desimone_haroon_2011, title={Institutional Profile: The Carolina Center of Cancer Nanotechnology Excellence: past accomplishments and future perspectives}, volume={6}, ISSN={1743-5889 1748-6963}, url={http://dx.doi.org/10.2217/nnm.10.142}, DOI={10.2217/nnm.10.142}, abstractNote={ The Carolina Center of Cancer Nanotechnology Excellence (C-CCNE) is funded by the National Cancer Institute and is based at the University of North Carolina. The C-CCNE features interactions between physical and biological scientists in a series of projects and cores that work together to quickly harness innovations in nanotechnology for the early diagnosis and treatment of cancer. Two key focus areas of the C-CCNE are, first, the selective delivery of drugs and imaging agents utilizing advanced nanoparticle technology, and second, novel approaches to imaging and radiotherapy utilizing carbon nanotube-based x-ray sources. }, number={1}, journal={Nanomedicine}, publisher={Future Medicine Ltd}, author={Juliano, Rudy L and Sunnarborg, Susan and DeSimone, Joseph and Haroon, Zishan}, year={2011}, month={Jan}, pages={19–24} } @inbook{galloway_murphy_rolland_herlihy_petros_napier_desimone_2010, title={Micromolding for the Fabrication of Biological Microarrays}, ISBN={9781934115954 9781597455510}, ISSN={1064-3745 1940-6029}, url={http://dx.doi.org/10.1007/978-1-59745-551-0_15}, DOI={10.1007/978-1-59745-551-0_15}, abstractNote={The PRINT® (pattern replication in non-wetting templates) process has been developed as a simple, gentle way to pattern films or generate discrete particles in arrays out of either pure biological materials or biomolecules encapsulated within polymeric materials. Patterned films and particle arrays can be fabricated in a wide array of sizes and shapes using Fluorocur® (a UV-curable perfluoropolyether polymer) from the nanometer to micron scale.}, booktitle={Methods in Molecular Biology}, publisher={Humana Press}, author={Galloway, Ashley L. and Murphy, Andrew and Rolland, Jason P. and Herlihy, Kevin P. and Petros, Robby A. and Napier, Mary E. and DeSimone, Joseph M.}, year={2010}, month={Sep}, pages={249–260} } @article{nunes_herlihy_mair_superfine_desimone_2010, title={Multifunctional Shape and Size Specific Magneto-Polymer Composite Particles}, volume={10}, ISSN={["1530-6992"]}, DOI={10.1021/nl904152e}, abstractNote={Interest in uniform multifunctional magnetic particles is driven by potential applications in biomedical and materials science. Here we demonstrate the fabrication of highly tailored nanoscale and microscale magneto-polymer composite particles using a template based approach. Regiospecific surface functionalization of the particles was performed by chemical grafting and evaporative Pt deposition. Manipulation of the particles by an applied magnetic field was demonstrated in water and hydrogen peroxide.}, number={4}, journal={NANO LETTERS}, author={Nunes, Janine and Herlihy, Kevin P. and Mair, Lamar and Superfine, Richard and DeSimone, Joseph M.}, year={2010}, month={Apr}, pages={1113–1119} } @misc{desimone_siripurapu_khan_spontak_royer_2010, title={Nano-and micro-cellular foamed thin-walled material, and processes and apparatuses for making the same}, volume={7,658,989}, number={2010 Feb. 9}, author={DeSimone, J. M. and Siripurapu, S. and Khan, S. A. and Spontak, R. J. and Royer, J.}, year={2010} } @article{merkel_herlihy_nunes_orgel_rolland_desimone_2010, title={Scalable, Shape-Specific, Top-Down Fabrication Methods for the Synthesis of Engineered Colloidal Particles}, volume={26}, ISSN={["0743-7463"]}, DOI={10.1021/la903890h}, abstractNote={The search for a method to fabricate nonspherical colloidal particles from a variety of materials is of growing interest. As the commercialization of nanotechnology continues to expand, the ability to translate particle-fabrication methods from a laboratory to an industrial scale is of increasing significance. In this feature article, we examine several of the most readily scalable top-down methods for the fabrication of such shape-specific particles and compare their capabilities with respect to particle composition, size, shape, and complexity as well as the scalability of the method. We offer an extensive examination of particle replication in nonwetting templates (PRINT) with regard to the versatility and scalability of this technique. We also detail the specific methods used in PRINT particle fabrication, including harvesting, purification, and surface-modification techniques, with an examination of both past and current methods.}, number={16}, journal={LANGMUIR}, author={Merkel, Timothy J. and Herlihy, Kevin P. and Nunes, Janine and Orgel, Ryan M. and Rolland, Jason P. and DeSimone, Joseph M.}, year={2010}, month={Aug}, pages={13086–13096} } @article{brown_zhang_forman_maynor_betts_desimone_jaeger_2010, title={Shear thickening in densely packed suspensions of spheres and rods confined to few layers}, volume={54}, ISSN={0148-6055 1520-8516}, url={http://dx.doi.org/10.1122/1.3474580}, DOI={10.1122/1.3474580}, abstractNote={We investigate confined shear thickening suspensions for which the sample thickness is comparable to the particle dimensions. Rheometry measurements are presented for densely packed suspensions of spheres and rods with aspect ratios 6 and 9. By varying the suspension thickness in the direction of the shear gradient at constant shear rate, we find pronounced oscillations in the stress. These oscillations become stronger as the gap size is decreased, and the stress is minimized when the sample thickness becomes commensurate with an integer number of particle layers. Despite this confinement-induced effect, viscosity curves show shear thickening that retains bulk behavior down to samples as thin as two particle diameters for spheres, below which the suspension is jammed. Rods exhibit similar behavior commensurate with the particle width, but they show additional effects when the thickness is reduced below about a particle length as they are forced to align; the stress increases for decreasing gap size at fix...}, number={5}, journal={Journal of Rheology}, publisher={Society of Rheology}, author={Brown, Eric and Zhang, Hanjun and Forman, Nicole A. and Maynor, Benjamin W. and Betts, Douglas E. and DeSimone, Joseph M. and Jaeger, Heinrich M.}, year={2010}, month={Sep}, pages={1023–1046} } @misc{petros_desimone_2010, title={Strategies in the design of nanoparticles for therapeutic applications}, volume={9}, ISSN={["1474-1784"]}, DOI={10.1038/nrd2591}, abstractNote={Engineered nanoparticles have the potential to revolutionize the diagnosis and treatment of many diseases; for example, by allowing the targeted delivery of a drug to particular subsets of cells. However, so far, such nanoparticles have not proved capable of surmounting all of the biological barriers required to achieve this goal. Nevertheless, advances in nanoparticle engineering, as well as advances in understanding the importance of nanoparticle characteristics such as size, shape and surface properties for biological interactions, are creating new opportunities for the development of nanoparticles for therapeutic applications. This Review focuses on recent progress important for the rational design of such nanoparticles and discusses the challenges to realizing the potential of nanoparticles.}, number={8}, journal={NATURE REVIEWS DRUG DISCOVERY}, author={Petros, Robby A. and DeSimone, Joseph M.}, year={2010}, month={Aug}, pages={615–627} } @article{wang_tian_petros_napier_desimone_2010, title={The Complex Role of Multivalency in Nanoparticles Targeting the Transferrin Receptor for Cancer Therapies}, volume={132}, ISSN={["0002-7863"]}, DOI={10.1021/ja1043177}, abstractNote={Transferrin receptor (TfR, CD71) has long been a therapeutic target due to its overexpression in many malignant tissues. In this study, PRINT() nanoparticles were conjugated with TfR ligands for targeted drug delivery. Cylindrical poly(ethylene glycol)-based PRINT nanoparticles (diameter (d) = 200 nm, height (h) = 200 nm) labeled with transferrin receptor antibody (NP-OKT9) or human transferrin (NP-hTf) showed highly specific TfR-mediated uptake by all human tumor cell lines tested, relative to negative controls (IgG1 for OKT9 or bovine transferrin (bTf) for hTf). The targeting efficiency was dependent on particle concentration, ligand density, dosing time, and cell surface receptor expression level. Interestingly, NP-OKT9 or NP-hTf showed little cytotoxicity on all solid tumor cell lines tested but were very toxic to Ramos B-cell lymphoma, whereas free OKT9 or hTf was not toxic. There was a strong correlation between TfR ligand density on the particle surface and cell viability and particle uptake. NP-OKT9 and NP-hTf were internalized into acidic intracellular compartments but were not localized in EEA1-enriched early endosomes or lysosomes. Elevated caspase 3/7 activity indicates activation of apoptosis pathways upon particle treatment. Supplementation of iron suppressed the toxicity of NP-OKT9 but not NP-hTf, suggesting different mechanisms by which NP-hTf and NP-OKT9 exerts cytotoxicity on Ramos cells. On the basis of such an observation, the complex role of multivalency in nanoparticles is discussed. In addition, our data clearly reveal that one must be careful in making claims of "lack of toxicity" when a targeting molecule is used on nanoparticles and also raise concerns for unanticipated off-target effects when one is designing targeted chemotherapy nanodelivery agents.}, number={32}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Wang, Jin and Tian, Shaomin and Petros, Robby A. and Napier, Mary E. and DeSimone, Joseph M.}, year={2010}, month={Aug}, pages={11306–11313} } @article{parrott_luft_byrne_fain_napier_desimone_2010, title={Tunable Bifunctional Silyl Ether Cross-Linkers for the Design of Acid-Sensitive Biomaterials}, volume={132}, ISSN={["0002-7863"]}, DOI={10.1021/ja108568g}, abstractNote={Responsive polymeric biomaterials can be triggered to degrade using localized environments found in vivo. A limited number of biomaterials provide precise control over the rate of degradation and the release rate of entrapped cargo and yield a material that is intrinsically nontoxic. In this work, we designed nontoxic acid-sensitive biomaterials based on silyl ether chemistry. A host of silyl ether cross-linkers were synthesized and molded into relevant medical devices, including Trojan horse particles, sutures, and stents. The resulting devices were engineered to degrade under acidic conditions known to exist in tumor tissue, inflammatory tissue, and diseased cells. The implementation of silyl ether chemistry gave precise control over the rate of degradation and afforded devices that could degrade over the course of hours, days, weeks, or months, depending upon the steric bulk around the silicon atom. These novel materials could be useful for numerous biomedical applications, including drug delivery, tissue repair, and general surgery.}, number={50}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Parrott, Matthew C. and Luft, J. Chris and Byrne, James D. and Fain, John H. and Napier, Mary E. and DeSimone, Joseph}, year={2010}, month={Dec}, pages={17928–17932} } @article{kim_rolland_carbonell_desimone_2010, title={Ultrathin Cross-Linked Perfluoropolyether Film Coatings from Liquid CO2 and Subsequent UV Curing}, volume={22}, ISSN={["0897-4756"]}, DOI={10.1021/cm903598v}, abstractNote={Ultrathin fluorinated films with highly solvent-resistant and optically clear characteristics were produced using liquid carbon dioxide free-meniscus coating followed by UV curing. Unique film morphologies including mesh and droplets structures resulted due to autophobic dewetting behavior of hydrophilic terminated perfluoropolyether.}, number={8}, journal={CHEMISTRY OF MATERIALS}, author={Kim, Jaehoon and Rolland, Jason P. and Carbonell, Ruben G. and DeSimone, Joseph M.}, year={2010}, month={Apr}, pages={2411–2413} } @article{kim_taylor_deyoung_mcclain_desimone_carbonell_2009, title={Deposition of Copper Particles and Films by the Displacement of Two Immiscible Supercritical Phases and Subsequent Reaction}, volume={21}, ISSN={0897-4756 1520-5002}, url={http://dx.doi.org/10.1021/cm802659j}, DOI={10.1021/cm802659j}, abstractNote={Copper (Cu) particles and films were produced by forming Cu(II) compound (Cu(hfac)2·H2O) films on substrates using a displacement from two immiscible supercritical phases (DISP) technique followed ...}, number={5}, journal={Chemistry of Materials}, publisher={American Chemical Society (ACS)}, author={Kim, Jaehoon and Taylor, Douglas and DeYoung, James and McClain, James B. and DeSimone, Joseph M. and Carbonell, Ruben G.}, year={2009}, month={Mar}, pages={913–924} } @article{zhang_nunes_gratton_herlihy_pohlhaus_desimone_2009, title={Fabrication of multiphasic and regio-specifically functionalized PRINT (R) particles of controlled size and shape}, volume={11}, ISSN={["1367-2630"]}, DOI={10.1088/1367-2630/11/7/075018}, abstractNote={Using Particle Replication In Nonwetting Templates (PRINT®) technology, multiphasic and regio-specifically functionalized shape-controlled particles have been fabricated that include end-labeled particles via post-functionalization; biphasic Janus particles that integrate two compositionally different chemistries into a single particle; and more complex multiphasic shape-specific particles. Controlling the anisotropic distribution of matter within a particle creates an extra parameter in the colloidal particle design, providing opportunities to generate advanced particles with versatile and tunable compositions, properties, and thus functionalities. Owing to their robust characteristics, these multiphasic and regio-specifically functionalized PRINT particles should be promising platforms for applications in life science and materials science.}, journal={NEW JOURNAL OF PHYSICS}, author={Zhang, H. and Nunes, J. K. and Gratton, S. E. A. and Herlihy, K. P. and Pohlhaus, P. D. and DeSimone, J. M.}, year={2009}, month={Jul} } @misc{du_kelly_roberts_desimone_2009, title={Fluoropolymer synthesis in supercritical carbon dioxide}, volume={47}, ISSN={["1872-8162"]}, DOI={10.1016/j.supflu.2008.11.011}, abstractNote={Herein we review the environmentally friendly synthesis of fluorinated polymers in supercritical carbon dioxide (scCO2). Historically, many high-performance fluorinated materials are commercially synthesized in aqueous media using fluorinated surfactants or in non-aqueous conditions using fluorinated solvents. Our group has pioneered both the homogeneous and heterogeneous polymerization of fluorinated monomers in scCO2. This review includes discussions on the synthesis of main-chain and side-chain fluoropolymers conducted via a chain-growth or continuous process. Specific materials consist of acrylate- and styrene-based systems, poly(vinyl ether)s, tetrafluoroethylene- and vinylidenefluoride-based, as well as novel fluorinated elastomers and thermoplastics.}, number={3}, journal={JOURNAL OF SUPERCRITICAL FLUIDS}, author={Du, Libin and Kelly, Jennifer Y. and Roberts, George W. and DeSimone, Joseph M.}, year={2009}, month={Jan}, pages={447–457} } @inproceedings{du_desimone_roberts_2009, title={Green Chemistry and Engineering with Gas Expanded Liquids and Near-Critical Media}, volume={90}, number={1006}, booktitle={ACS Symposium Series}, author={Du, L. and DeSimone, J.M. and Roberts, G.W.}, editor={Hutchenson, K.W. and Scurto, A.M. and Subramaniam, B.Editors}, year={2009}, pages={259–273} } @article{hu_finlay_chen_betts_hillmyer_callow_callow_desimone_2009, title={Photochemically Cross-Linked Perfluoropolyether-Based Elastomers: Synthesis, Physical Characterization, and Biofouling Evaluation}, volume={42}, ISSN={["1520-5835"]}, DOI={10.1021/ma901227k}, abstractNote={A series of reactive liquid perfluoropolyether (PFPE) precursors were synthesized which can be photochemically cross-linked (UV-cured) into high-performance PFPE elastomers in one step. To investigate how fundamental changes in the PFPE molecular structure correlate to bulk and surface properties, the variable functional end group, molecular weight, and the copolymer content were systematically explored in relation to thermal stability, contact angle/surface tension, modulus, and biofouling behavior. The morphologies of these PFPE materials were studied using differential scanning calorimetry, dynamic mechanical thermal analysis, and small-angle X-ray scattering. From these studies, it was determined that clusters of polymerized functional end groups were found to be nanophase separated within the PFPE matrix. By varying the cross-link density, the Young’s modulus of the fully cross-linked PFPE elastomeric film could be tuned from 1.5 to 90 MPa with a critical surface tension of 8.6−16 mN/m. The marine an...}, number={18}, journal={MACROMOLECULES}, author={Hu, Zhaokang and Finlay, John A. and Chen, Liang and Betts, Douglas E. and Hillmyer, Marc A. and Callow, Maureen E. and Callow, James A. and DeSimone, Joseph M.}, year={2009}, month={Sep}, pages={6999–7007} } @article{ko_tumbleston_zhang_williams_desimone_lopez_samulski_2009, title={Photonic Crystal Geometry for Organic Solar Cells}, volume={9}, ISSN={1530-6984 1530-6992}, url={http://dx.doi.org/10.1021/nl901232p}, DOI={10.1021/nl901232p}, abstractNote={We report organic solar cells with a photonic crystal nanostructure embossed in the photoactive bulk heterojunction layer, a topography that exhibits a 3-fold enhancement of the absorption in specific regions of the solar spectrum in part through multiple excitation resonances. The photonic crystal geometry is fabricated using a materials-agnostic process called PRINT wherein highly ordered arrays of nanoscale features are readily made in a single processing step over wide areas (approximately 4 cm(2)) that is scalable. We show efficiency improvements of approximately 70% that result not only from greater absorption, but also from electrical enhancements. The methodology is generally applicable to organic solar cells and the experimental findings reported in our manuscript corroborate theoretical expectations.}, number={7}, journal={Nano Letters}, publisher={American Chemical Society (ACS)}, author={Ko, Doo-Hyun and Tumbleston, John R. and Zhang, Lei and Williams, Stuart and DeSimone, Joseph M. and Lopez, Rene and Samulski, Edward T.}, year={2009}, month={Jul}, pages={2742–2746} } @misc{canelas_herlihy_desimone_2009, title={Top-down particle fabrication: control of size and shape for diagnostic imaging and drug delivery}, volume={1}, ISSN={["1939-0041"]}, DOI={10.1002/wnan.40}, abstractNote={AbstractThis review discusses rational design of particles for use as therapeutic vectors and diagnostic imaging agent carriers. The emerging importance of both particle size and shape is considered, and the adaptation and modification of soft lithography methods to produce nanoparticles are highlighted. To this end, studies utilizing particles made via a process called Particle Replication In Non‐wetting Templates are discussed. In addition, insights gained into therapeutic cargo and imaging agent delivery from related types of polymer‐based carriers are considered. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies }, number={4}, journal={WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY}, author={Canelas, Dorian A. and Herlihy, Kevin P. and DeSimone, Joseph M.}, year={2009}, pages={391–404} } @article{ahmed_desimone_roberts_2008, title={Continuous copolymerization of vinylidene fluoride with hexafluoropropylene in Supercritical carbon dioxide: High-hexafluoropropylene-content amorphous copolymers}, volume={41}, ISSN={["0024-9297"]}, DOI={10.1021/ma702526u}, abstractNote={Copolymerization of vinylidene fluoride (VF2) and hexafluoropropylene (HFP) was carried out in supercritical carbon dioxide using a continuous stirred tank reactor. Three different HFP/VF2 molar feed ratios were studied, 59:41, 66:34, and 73:27, giving rise to amorphous copolymers containing about 23, 26, and 30 mol % HFP, respectively. The experiments were carried out at 40 °C with pressures in the range of 207–400 bar using perfluorobutyryl peroxide as the free radical initiator. Depending on the copolymer composition, the molecular weight, and the reaction pressure, either a homogeneous (solution) or a heterogeneous (precipitation) polymerization was observed. The effects of feed monomer concentration and reaction pressure were explored at otherwise constant conditions. The rate of polymerization (Rp) and the number-average molecular weight (Mn) increased linearly with the total monomer concentration, independent of the mode of polymerization, i.e., homogeneous or heterogeneous. Both Rp and Mn increase...}, number={9}, journal={MACROMOLECULES}, author={Ahmed, Tamer S. and DeSimone, Joseph M. and Roberts, George W.}, year={2008}, month={May}, pages={3086–3097} } @article{herlihy_nunes_desimone_2008, title={Electrically driven alignment and crystallization of unique anisotropic polymer particles}, volume={24}, ISSN={["0743-7463"]}, DOI={10.1021/la801250g}, abstractNote={Micrometer-sized monodisperse anisotropic polymer particles, with disk, rod, fenestrated hexagon (hexnut), and boomerang shapes, were synthesized using the particle replication in nonwetting templates (PRINT) process, and investigations were conducted on aqueous suspensions of these particles when subjected to alternating electric fields. A coplanar electrode configuration, with 1 to 2 mm electrode gaps (20-50 V ac, 0.5-5.0 kHz) was used, and the experiments were monitored with fluorescence microscopy. For all particle suspensions, the field brought about significant changes in the packing and orientation. Extensive particle chaining and packing were observed for the disk, rod, and hexnut suspensions. Because of the size and geometry of the boomerang particles, limited chaining was observed; however, the field triggered a change from random to a more ordered packing arrangement.}, number={16}, journal={LANGMUIR}, author={Herlihy, Kevin P. and Nunes, Janine and DeSimone, Joseph M.}, year={2008}, month={Aug}, pages={8421–8426} } @article{ahmed_desimone_roberts_2009, title={Kinetics of the Homopolymerization of Vinylidene Fluoride and Its Copolymerization with Hexafluoropropylene in Supercritical Carbon Dioxide: The Locus of Polymerization}, volume={42}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma801911j}, DOI={10.1021/ma801911j}, abstractNote={In previous studies, the continuous polymerization of vinylidene fluoride (VF2) and mixtures of VF2 with hexafluoropropylene (HFP) was carried out in supercritical carbon dioxide (scCO2) using a continuous stirred-tank reactor (CSTR). Most of the polymerizations were heterogeneous; i.e., polymer particles precipitated during the reaction. However, some were homogeneous, especially at higher HFP concentrations. In this study, the data from the earlier experiments have been tested against three kinetic models to determine the primary locus of the heterogeneous polymerizations. The first model, the “solution polymerization” model, is based on the assumption that all of the polymerization reactions take place in the continuous, CO2-rich phase, with no reaction in the polymer phase. In the second model, the “surface polymerization” model, chain initiation occurs in the continuous phase, while chain propagation and termination occur in a thin zone on the surface of the polymer particles. The third model, the “i...}, number={1}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Ahmed, Tamer S. and DeSimone, Joseph M. and Roberts, George W.}, year={2009}, month={Jan}, pages={148–155} } @article{gratton_napier_ropp_tian_desimone_2008, title={Microfabricated Particles for Engineered Drug Therapies: Elucidation into the Mechanisms of Cellular Internalization of PRINT Particles}, volume={25}, ISSN={["1573-904X"]}, DOI={10.1007/s11095-008-9654-8}, abstractNote={To investigate the cellular internalization pathways of shape- and size-specific particles as a function of zeta potential in different cell types. A top-down particle fabrication technique called PRINT was utilized to fabricate monodisperse 1 μm cylindrical particles. Cellular internalization of these PRINT particles was monitored using confocal microscopy, flow cytometry, and transmission electron microscopy. The endocytic pathway used by 1 μm cationic PRINT particles was evaluated using different inhibitory strategies. Cytotoxicity assays were used to determine the toxicity of both cationic and anionic PRINT particles in multiple cell types. Particle internalization was confirmed using confocal microscopy, flow cytometry and transmission electron microscopy. The mechanism of internalization of positively charged PRINT particles was found to be predominantly clathrin-mediated endocytosis and macropinocytosis with very few particles utilizing a caveolae-mediated endocytic pathway. The exposed charge on the surface of the particles had a significant effect on the rate of endocytosis in all cell types tested, except for the macrophage cells. No significant cytotoxicity was observed for all PRINT particles used in the present study. Cylindrical 1 μm PRINT particles were readily internalized into HeLa, NIH 3T3, OVCAR-3, MCF-7, and RAW 264.7 cells. Particles with a positive zeta potential exhibited an enhanced rate of endocytosis compared to negatively charged particles with identical sizes and shapes. It was found that PRINT particles with a positive zeta potential were endocytosed into HeLa cells using predominantely clathrin-mediated and macropinocytotic pathways.}, number={12}, journal={PHARMACEUTICAL RESEARCH}, author={Gratton, Stephanie E. A. and Napier, Mary E. and Ropp, Patricia A. and Tian, Shaomin and DeSimone, Joseph M.}, year={2008}, month={Dec}, pages={2845–2852} } @article{yu-su_thomas_alford_larue_pitsikalis_hadjichristidis_desimone_dobrynin_sheiko_2008, title={Molding Block Copolymer Micelles: A Framework for Molding of Discrete Objects on Surfaces}, volume={24}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la802549s}, DOI={10.1021/la802549s}, abstractNote={Soft lithography based on photocurable perfluoropolyether (PFPE) was used to mold and replicate poly(styrene-b-isoprene) block-copolymer micelles within a broad range of shapes and sizes including spheres, cylinders, and torroids. These physically assembled nanoparticles were first formed in a selective solvent for one block then deposited onto substrates having various surface energies in an effort to minimize the deformation of the micelles due to attractive surface forces. The successful molding of these delicate nanoparticles underscores two advantages of PFPE as a molding material. First, it allows one to minimize particle deformation due to adsorption by using low energy substrates. Second, PFPE is not miscible with the organic micelles and thus prevents their dissociation. For spherical PS-b-PI micelles, a threshold value of the substrate surface energy for the mold to lift-off cleanly, that is, the particles remain adhered to the substrate after mold removal was determined to be around gamma congruent with 54 mJ/m2. For substrates with higher surface energies (>54 mJ/m2), the micelles undergo flattening which increase the contact area and thus facilitate molding, although at the expense of particle deformation. The results are consistent with theoretical predictions of a molding range for substrate surface energies, which depends on the size, shape, and mechanical properties of the particles. In a similar fashion, cylindrical PS-b-PI micelles remain on the substrate at surface energies gamma>or=54 mJ/m2 after a mold removal. However, cylindrical micelles behaved differently at lower surface energies. These micelles ruptured due to their inability to slide on the surfaces during mold lift-off. Thus, the successful molding of extended objects is attainable only when the particle is adsorbed on higher energy substrates where deformation can still be kept at a minimum by using stronger materials such as carbon nanotubes for the master.}, number={21}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Yu-Su, Sherryl Y. and Thomas, David R. and Alford, Jonathan E. and LaRue, Isaac and Pitsikalis, Marinos and Hadjichristidis, Nikos and DeSimone, Joseph M. and Dobrynin, Andrey V. and Sheiko, Sergei S.}, year={2008}, month={Nov}, pages={12671–12679} } @article{williams_hampton_gowrishankar_ding_templeton_samulski_desimone_mcgehee_2008, title={Nanostructured Titania−Polymer Photovoltaic Devices Made Using PFPE-Based Nanomolding Techniques}, volume={20}, ISSN={0897-4756 1520-5002}, url={http://dx.doi.org/10.1021/cm800729q}, DOI={10.1021/cm800729q}, abstractNote={We fabricated ordered bulk heterojunction photovoltaic (PV) cells using a perfluoropolyether (PFPE) elastomeric mold to control the donor−acceptor interfacial morphology within devices. Anatase titania nanostructures with postlike features ranging from 30 to 100 nm in height and 30 to 65 nm in spacing were fabricated using the Pattern Replication In Nonwetting Templates (PRINT) process. The nanostructured devices showed a 2-fold improvement in both short-circuit current (Jsc) and power conversion efficiency (PCE) relative to reference bilayer cells. Additionally, the titania was functionalized with Z907 dye to increase both the short-circuit current (Jsc) and open-circuit voltage (Voc). As a result we observed a device efficiency (ηeff) of 0.6%, the highest recorded efficiency value so far for an imprinted titania−P3HT device.}, number={16}, journal={Chemistry of Materials}, publisher={American Chemical Society (ACS)}, author={Williams, Stuart S. and Hampton, Meredith J. and Gowrishankar, Vignesh and Ding, I-Kang and Templeton, Joseph L. and Samulski, Edward T. and DeSimone, Joseph M. and McGehee, Michael D.}, year={2008}, month={Aug}, pages={5229–5234} } @article{hu_chen_betts_pandya_hillmyer_desimone_2008, title={Optically Transparent, Amphiphilic Networks Based on Blends of Perfluoropolyethers and Poly(ethylene glycol)}, volume={130}, ISSN={["0002-7863"]}, DOI={10.1021/ja803991n}, abstractNote={Amphiphilic networks of perfluoropolyethers (PFPE) and poly(ethylene glycol) (PEG) have been achieved to yield optically transparent, mechanically robust films over a wide range of compositions. Telechelic diols of these oligomers were transformed to a photocurable dimethacryloxy form (DMA) and free radically cured at various composition weight ratios to yield free-standing films. Clear and colorless amphiphilic networks could be achieved when low molar mass versions of both the PFPE-DMA (1 kg/mol) and the PEG-DMA (550 g/mol) were used. The bulk morphologies of the samples were extensively characterized by a variety of techniques including ultraviolet-visible spectroscopy, differential scanning calorimetry, dynamic mechanic thermal analysis, small-angle X-ray scattering, atomic force microscopy, X-ray photoelectron spectroscopy, and optical microscopy, which strongly suggest that nanoscopic to macroscopic phase-separated materials could be achieved. By incorporating a threshold amount of PFPEs into PEG-based hydrogel networks, water swelling could be significantly reduced, which may offer a new strategy for a number of medical device applications. Along these lines, strong inhibition of nonspecific protein adsorption could be achieved with these amphiphilic network materials compared with an oligo(ethylene glycol)-based self-assembled monolayer coated surface.}, number={43}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Hu, Zhaokang and Chen, Liang and Betts, Douglas E. and Pandya, Ashish and Hillmyer, Marc A. and DeSimone, Joseph M.}, year={2008}, month={Oct}, pages={14244–14252} } @article{petros_ropp_desimone_2008, title={Reductively Labile PRINT Particles for the Delivery of Doxorubicin to HeLa Cells}, volume={130}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja801436j}, DOI={10.1021/ja801436j}, abstractNote={A Trojan horse PRINT particle composition was developed that incorporates a reductively labile cross-linker to achieve activated release of doxorubicin in vitro. Particles of discrete size and shape (cube side length = 2 micron) containing 30 wt % of a disulfide-based cross-linker and 2 wt % doxorubicin were synthesized. This PRINT composition was shown to release doxorubicin in response to a reducing environment as measured by flow cytometry and was found to be highly proficient at killing HeLa cells in vitro.}, number={15}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Petros, Robby A. and Ropp, Patricia A. and DeSimone, Joseph M.}, year={2008}, month={Apr}, pages={5008–5009} } @article{kelly_desimone_2008, title={Shape-specific, monodisperse nano-molding of protein particles}, volume={130}, ISSN={["0002-7863"]}, DOI={10.1021/ja8014428}, abstractNote={Herein we report nano-molding proteins for the fabrication of protein PRINT particles of monodisperse size and shape. Lyophilized protein particles are generally highly dispersed in particle size, aggregated, and often made through costly and complicated processes. Attempts to engineer monodisperse, discrete protein particles using wet-milling, spray-freeze-drying, microemulsion, or super critical fluid methods have realized little success. The PRINT technology enables a gentle, facile route to monodisperse particles of 100% protein as small as 200 nm cylinders. Protein PRINT particles of any shape and size are effortlessly achievable. Our research efforts include making PRINT particles composed of albumin and albumin 0.5 wt % siRNA, and Abraxane, the gold standard therapeutic used in metastatic breast cancer.}, number={16}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Kelly, Jennifer Y. and DeSimone, Joseph M.}, year={2008}, month={Apr}, pages={5438-+} } @misc{gratton_williams_napier_pohlhaus_zhou_wiles_maynor_shen_olafsen_samulski_et al._2008, title={The Pursuit of a Scalable Nanofabrication Platform for Use in Material and Life Science Applications}, volume={41}, ISSN={["1520-4898"]}, DOI={10.1021/ar8000348}, abstractNote={In this Account, we describe the use of perfluoropolyether (PFPE)-based materials that are able to accurately mold and replicate micro- and nanosized features using traditional techniques such as embossing as well as new techniques that we developed to exploit the exceptional surface characteristics of fluorinated substrates. Because of the unique partial wetting and nonwetting characteristics of PFPEs, we were able to go beyond the usual molding and imprint lithography approaches and have created a technique called PRINT (Particle [or Pattern] Replication In Nonwetting Templates). PRINT is a distinctive "top-down" fabrication technique capable of generating isolated particles, arrays of particles, and arrays of patterned features for a plethora of applications in both nanomedicine and materials science. A particular strength of the PRINT technology is the high-resolution molding of well-defined particles with precise control over size, shape, deformability, and surface chemistry. The level of replication obtained showcases some of the unique characteristics of PFPE molding materials. In particular, these materials arise from very low surface energy precursors with positive spreading coefficients, can be photocured at ambient temperature, and are minimally adhesive, nonswelling, and conformable. These distinctive features enable the molding of materials with unique attributes and nanometer resolution that have unprecedented scientific and technological value. For example, in nanomedicine, the use of PFPE materials with the PRINT technique allows us to design particles in which we can tailor key therapeutic parameters such as bioavailability, biodistribution, target-specific cell penetration, and controlled cargo release. Similarly, in materials science, we can fabricate optical films and lens arrays, replicate complex, naturally occurring objects such as adenovirus particles, and create 2D patterned arrays of inorganic oxides.}, number={12}, journal={ACCOUNTS OF CHEMICAL RESEARCH}, author={Gratton, Stephanie E. A. and Williams, Stuart S. and Napier, Mary E. and Pohlhaus, Patrick D. and Zhou, Zhilian and Wiles, Kenton B. and Maynor, Benjamin W. and Shen, Clifton and Olafsen, Tove and Samulski, Edward T. and et al.}, year={2008}, month={Dec}, pages={1685–1695} } @article{gratton_ropp_pohlhaus_luft_madden_napier_desimone_2008, title={The effect of particle design on cellular internalization pathways}, volume={105}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.0801763105}, abstractNote={The interaction of particles with cells is known to be strongly influenced by particle size, but little is known about the interdependent role that size, shape, and surface chemistry have on cellular internalization and intracellular trafficking. We report on the internalization of specially designed, monodisperse hydrogel particles into HeLa cells as a function of size, shape, and surface charge. We employ a top-down particle fabrication technique called PRINT that is able to generate uniform populations of organic micro- and nanoparticles with complete control of size, shape, and surface chemistry. Evidence of particle internalization was obtained by using conventional biological techniques and transmission electron microscopy. These findings suggest that HeLa cells readily internalize nonspherical particles with dimensions as large as 3 μm by using several different mechanisms of endocytosis. Moreover, it was found that rod-like particles enjoy an appreciable advantage when it comes to internalization rates, reminiscent of the advantage that many rod-like bacteria have for internalization in nonphagocytic cells.}, number={33}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Gratton, Stephanie E. A. and Ropp, Patricia A. and Pohlhaus, Patrick D. and Luft, J. Christopher and Madden, Victoria J. and Napier, Mary E. and DeSimone, Joseph M.}, year={2008}, month={Aug}, pages={11613–11618} } @article{hampton_williams_zhou_nunes_ko_templeton_samulski_desimone_2008, title={The patterning of sub-500 nm inorganic oxide structures}, volume={20}, DOI={10.1002/adma.200702495}, abstractNote={Elastomeric perfluoropolyether molds are applied to pattern arrays of sub-500 nm inorganic oxide features. This versatile soft-lithography technique can be used to pattern a wide range of materials; in this work inorganic oxides including TiO2 , SnO2 , ZnO, ITO, and BaTiO3 are patterned on a variety of substrates with different aspect ratios. An example of TiO2 posts is shown in the figure.}, number={14}, journal={Advanced Materials}, author={Hampton, M. J. and Williams, S. S. and Zhou, Z. and Nunes, J. and Ko, D. H. and Templeton, J. L. and Samulski, E. T. and DeSimone, J. M.}, year={2008}, pages={2667-} } @article{guo_resnick_efimenko_genzer_desimone_2008, title={Alternative fluoropolymers to avoid the challenges associated with perfluorooctanoic acid}, volume={47}, ISSN={["0888-5885"]}, DOI={10.1021/ie0703179}, abstractNote={The degradation of stain-resistant coating materials leads to the release of biopersistent perfluorooctanoic acid (PFOA) to the environment. In order to find the environmentally friendly substitutes, we have designed and synthesized a series of nonbiopersistant fluorinated polymers containing perfluorobutyl groups in the side chains. The surface properties of the new coating materials were characterized by static and dynamic contact angle measurements. The new coating materials demonstrate promising hydrophobic and oleophobic properties with low surfaces tensions. The wetting properties and surface structure of the polymers were tuned by varying the “spacer” structures between the polymer backbones and the perfluorinated groups of the side chains. The relationship between orientations of the fluorinated side chains and performances of polymer surfaces were further investigated by near-edge X-ray fine absorption structure (NEXAFS) experiments and differential scanning calorimetry (DSC).}, number={3}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Guo, Ji and Resnick, Paul and Efimenko, Kirill and Genzer, Jan and DeSimone, Joseph M.}, year={2008}, month={Feb}, pages={502–508} } @article{ahmed_desimone_roberts_2007, title={Continuous copolymerization of vinylidene fluoride with hexafluoropropylene in Supercritical carbon dioxide: Low hexafluoropropylene content semicrystalline copolymers}, volume={40}, ISSN={["0024-9297"]}, DOI={10.1021/ma0713613}, abstractNote={The copolymerization of vinylidene fluoride with hexafluoropropylene (HFP) was carried out in supercritical carbon dioxide by precipitation polymerization using a continuous stirred tank reactor. Copolymers with ca. 10 mol % HFP were synthesized at 40 °C and pressures in the range of 207−400 bar using perfluorobutyryl peroxide as the free radical initiator. The effects of feed monomer concentration and reaction pressure were both explored at otherwise constant conditions. The rate of polymerization (Rp) and the number-average molecular weight (Mn) increased linearly with the total monomer concentration up to about 6 M, the highest concentration investigated. The Rp and the Mn were strongly influenced by the reaction pressure. An 80% increase in both Rp and Mn was observed when the reaction pressure rose from 207 to 400 bar. The molecular weight distributions of the synthesized copolymer showed a long tail that increased to become a broad shoulder with increasing total monomer concentration. This tail incr...}, number={26}, journal={MACROMOLECULES}, author={Ahmed, Tamer S. and DeSimone, Joseph M. and Roberts, George W.}, year={2007}, month={Dec}, pages={9322–9331} } @article{choi_coble_branham_desimone_murray_2007, title={Dynamics of CO2-Plasticized Electron Transport in Au Nanoparticle Films:  Opposing Effects of Tunneling Distance and Local Site Mobility}, volume={111}, ISSN={1932-7447 1932-7455}, url={http://dx.doi.org/10.1021/jp068349h}, DOI={10.1021/jp068349h}, abstractNote={The electron-transport properties of unlinked and linked solid-state films of very small “Au38” nanoparticles (monolayer protected clusters, or MPCs) remarkably change in opposing directions upon contact with increasing pressures of CO2 gas (0∼6.6 MPa). Electronic conductivities (σEL) of dropcast, unlinked Au MPC films increase up to 31-fold with increasing CO2 pressure, while σEL of dithiol-linked Au MPC films decreases with increasing CO2 pressure. In conductivity by electron hopping between electron donor and acceptor Au MPC cores, the organic protecting ligands serve as a solvent shell whose properties influence the dynamics of electron transport. Exposure of Au MPC films to CO2 and consequent swelling by CO2 (or organic vapor) sorption into the monolayers changes two key factors:  core edge-to-edge electron tunneling distances (dHOP) and a previously underappreciated effect of dimension and/or frequency of local core thermal motions. Swelling induces increases in both, but depending on which factor i...}, number={9}, journal={The Journal of Physical Chemistry C}, publisher={American Chemical Society (ACS)}, author={Choi, Jai-Pil and Coble, Melissa M. and Branham, Matthew R. and DeSimone, Joseph M. and Murray, Royce W.}, year={2007}, month={Feb}, pages={3778–3785} } @article{li_yang_jones_desimone_irene_2007, title={Etching SiO[sub 2] with HF/pyridine-supercritical carbon dioxide solutions and resultant interfacial electronic properties}, volume={25}, ISSN={1071-1023}, url={http://dx.doi.org/10.1116/1.2743651}, DOI={10.1116/1.2743651}, abstractNote={Silicon dioxide (SiO2) films grown on single crystal Si in high temperature O2 were etched using nonaqueous HF/pyridine solutions in supercritical CO2. The etch rate of SiO2 films were studied in the solutions with HF concentration up to 1000μM at 1.38×107Pa and at 35, 45, and 55°C. Capacitance versus voltage, conductance versus voltage, and leakage current measurements were performed on capacitor structures fabricated after SiO2 regrowth on completely etched Si surfaces. The electronic results revealed no systematic differences of etched and unetched samples with various etch times concentrations and that the Si–SiO2 interface of completely etched samples was comparable to the unetched control sample in terms of interface electronic charge and states and leakage current.}, number={4}, journal={Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures}, publisher={American Vacuum Society}, author={Li, Y. X. and Yang, D. and Jones, C. A. and DeSimone, J. M. and Irene, E. A.}, year={2007}, pages={1139} } @article{gratton_pohhaus_lee_guo_cho_desimone_2007, title={Nanofabricated particles for engineered drug therapies: A preliminary Biodistribution study of PRINT (TM) nanoparticles}, volume={121}, ISSN={["0168-3659"]}, DOI={10.1016/j.jconrel.2007.05.027}, abstractNote={A novel method for the fabrication of polymeric particles on the order of tens of nanometers to several microns is described. This imprint lithographic technique called PRINT™ (Particle Replication In Non-wetting Templates), takes advantage of the unique properties of elastomeric molds comprised of a low surface energy perfluoropolyether network, allowing the production of monodisperse, shape-specific nanoparticles from an extensive array of organic precursors. This engineered nature of particle production has a number of advantages over the construction of traditional nanoparticles such as liposomes, dendrimers, and colloidal precipitates. The gentle "top down" approach of PRINT enables the simultaneous and independent control over particle size and shape, composition, and surface functionality, and permits the loading of delicate cargos such as small organic therapeutics and biological macromolecules. Thus, this single tool serves as a comprehensive platform for the rational design and investigation of new nanocarriers in medicine, having applications ranging from therapeutics to advanced diagnostics. Preliminary in vitro and in vivo studies were conducted, demonstrating the future utility of PRINT particles as delivery vectors in nanomedicine. Monodisperse 200 nm poly(ethylene glycol)-based (PEG) particles were fabricated using PRINT methodology and characterized via scanning electron microscopy and dynamic light scattering. Incubation with HeLa cells showed very little cytotoxicity, even at high concentrations. The biodistribution and pharmacokinetics of [125I]-labeled particles were studied in healthy mice following bolus tail vein administration. The particles were distributed mainly to the liver and the spleen with an apparent distribution t1/2 of approximately 17 min followed by slow redistribution with a t1/2 of 3.3 h. The volume of distribution for the central and peripheral compartments was found to be approximately 3 mL and 5 mL, respectively.}, number={1-2}, journal={JOURNAL OF CONTROLLED RELEASE}, author={Gratton, Stephanie E. A. and PohhauS, Patrick D. and Lee, Jin and Guo, Ii and Cho, Moo J. and DeSimone, Joseph M.}, year={2007}, month={Aug}, pages={10–18} } @article{napier_desimone_2007, title={Nanoparticle Drug Delivery Platform}, volume={47}, ISSN={1558-3724}, url={http://dx.doi.org/10.1080/15583720701454999}, DOI={10.1080/15583720701454999}, abstractNote={The use of polymers and polymeric structures in the treatment, diagnosis, and monitoring of biological systems is continuing to increase in sophistication. Research exploring the use of nanoparticles for drug delivery applications has included the exploration and development of nanocolloids, liposomes, micelles, nanogels, polymer‐drug conjugates, and a variety of other polymeric nanoparticles that are composed of organic polymers with specific physical or chemical properties that make them relevant delivery vehicles. One of the current trends is the fabrication of tunable, mono‐dispersed, polymeric nanostructures to be used as nanoparticle drug delivery platforms. The PRINT technology used to fabricate monodisperse particles from a wide range of particle matrix materials including biocompatible poly(ethylene glycol) and bioabsorbable poly(d‐lactic acid) is described along with an abbreviated overview of other polymeric drug delivery platforms.}, number={3}, journal={Polymer Reviews}, publisher={Informa UK Limited}, author={Napier, Mary E. and DeSimone, Joseph M.}, year={2007}, month={Jul}, pages={321–327} } @inbook{canelas_desimone_1997, place={Heidelberg, Germany}, series={Advances in Polymer Science}, title={Polymerizations in Liquid and Supercritical Carbon Dioxide}, ISBN={9783540626992 9783540684428}, url={http://dx.doi.org/10.1007/3-540-68442-5_3}, DOI={10.1007/3-540-68442-5_3}, booktitle={Metal Complex Catalysts Supercritical Fluid Polymerization Supramolecular Architecture}, publisher={Springer Berlin}, author={Canelas, Dorian A. and DeSimone, Joseph M.}, editor={Canelas, D.A. and DeSimone, J.M. and Harada, A. and Ihara, E. and Mashima, K. and Nakamura, A. and Nakayama, Y. and Yasuda, H.Editors}, year={1997}, pages={103–140}, collection={Advances in Polymer Science} } @article{maynor_larue_hu_rolland_pandya_fu_liu_spontak_sheiko_samulski_et al._2007, title={Supramolecular nanomimetics: Replication of micelles, viruses, and other naturally occurring nanoscale objects}, volume={3}, ISSN={["1613-6810"]}, DOI={10.1002/smll.200600507}, abstractNote={Naturally occurring supramolecular objects, such as proteins, micelles, and viruses, exhibit sophisticated morphological shapes or surface motifs that conventional synthetic and fabrication techniques cannot replicate. These structures owe their interesting shapes and shape-related properties largely to noncovalent chemical interactions that can produce unique, “evolutionarily designed” shapes with nanometer precision. These “self-assembly”-driven approaches can be tremendously successful in controlling nanoscale shape in organic and inorganic materials, but the chemical structure of each component must be carefully designed and precisely synthesized to ensure that the desired morphology is obtained. Even if the chemical design of the material is sufficient to promote the desired assembly process, factors such as temperature, solution purity, and kinetic limitations can significantly, and often detrimentally, affect the resulting morphology of “bottom-up” self-assembled materials. Alternatively, traditional microand nanofabrication approaches can reproducibly fabricate precise, regular shapes out of a variety of robust materials, but the morphologies are typically limited to geometric shapes and therefore cannot easily mimic the structural complexity that can be created by self-assembled organic and biological structures, such as viruses. In this work, we report a nanofabrication method that is able to reproduce shapes normally associated with self-assembly using robust nanoscale replication methods, thereby combining the morphological sophistication of the natural world with the scalable processing technologies associated with lithography. Specifically, we use extremely low surface energy, minimally adhesive, low-viscosity, ambient-temperature photoACHTUNGTRENNUNGcurable perfluoropolyether (PFPE) elastomers to replicate naturally occurring objects (“master templates”). The naturally occurring motif is replicated in the PFPE elastomer by pouring the curable PFPE resin over the master template and photopolymerizing the resin into a flexible “mold” that transfers the details of the master morphology into a crosslinked fluoropolymer (cf. Figure 1 A). Due to the extremely low surface energy (8–10 dyncm 1 depending on chemical structure) of the PFPE precursor resin, it will spontaneously spread on materials with a critical surface tension greater than 8–10 dyncm , which includes almost all substrates found in nature, including organic materials. 6] In addition, owing to the chemical inertness and low solubility parameter of the resin, these PFPE molds can then be used to make replicas of naturally occurring masters from a variety of materials with good fidelity. To demonstrate the ability of this strategy to mimic self-assembled structures that are freely lying on a substrate, we chose to replicate block-copolymer micelles and virus particles. In sharp contrast to the simple geometric structures typically produced by molding technologies using man-made microfabricated master templates, this process permits high-definition replication of a wide variety of self-assembled fragile and even metastable transient nano-objects, which may have applications in sensing, materials science, and medicine. By dissolving amphiphilic block copolymers, such as polyACHTUNGTRENNUNG(styrene)-block-polyACHTUNGTRENNUNG(isoprene) (PS-b-PI), in a solvent that is a thermodynamically good solvent for one block and a poor solvent for the other block (e.g., n-heptane), one observes the aggregation of block-copolymer molecules into micellar structures. Depending on the molecular and physical properties of the system, this diblock copolymer exhibits a variety of well-defined morphologies including [*] Dr. B. W. Maynor, Dr. I. LaRue, Z. Hu, Dr. J. P. Rolland, Dr. A. Pandya, Prof. S. S. Sheiko, Prof. E. T. Samulski, Prof. J. M. DeSimone Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill, NC 27599 (USA) Fax: (+1)919-962-5467 E-mail: desimone@unc.edu}, number={5}, journal={SMALL}, author={Maynor, Benjamin W. and LaRue, Isaac and Hu, Zhaokang and Rolland, Jason P. and Pandya, Ashish and Fu, Qiang and Liu, Jie and Spontak, Richard J. and Sheiko, Sergei S. and Samulski, Richard J. and et al.}, year={2007}, month={May}, pages={845–849} } @article{russell-tanner_takayama_sugimura_desimone_samulski_2007, title={Weak surface anchoring energy of 4-cyano-4′-pentyl-1,1′-biphenyl on perfluoropolyether Langmuir-Blodgett films}, volume={126}, ISSN={0021-9606 1089-7690}, url={http://dx.doi.org/10.1063/1.2743404}, DOI={10.1063/1.2743404}, abstractNote={Functional director alignment layers are needed for high performance liquid crystal displays (LCDs). Reported herein is a novel polymer material for LC alignment, namely, perfluoropolyether (PFPE), which exhibits a weak surface anchoring energy for bend deformation and is amenable to simple fabrication of grooved surfaces by soft lithography, a surface topography desired for multistable LCDs. Liquid crystal optical cells fabricated using Langmuir-Blodgett films of PFPE (of variable thickness) exhibited weak surface anchoring energies on the order of 10−5J∕m2 for the nematic liquid crystal 4-cyano-4′-pentyl-1,1′-biphenyl with no dependence on film thickness.}, number={24}, journal={The Journal of Chemical Physics}, publisher={AIP Publishing}, author={Russell-Tanner, Joette M. and Takayama, Sadao and Sugimura, Akihiko and DeSimone, Joseph M. and Samulski, Edward T.}, year={2007}, month={Jun}, pages={244706} } @article{boggiano_vellenga_carbonell_ashby_desimone_2006, title={Alicyclic photoresists for CO2-based next-generation microlithography: A tribute to James E. McGrath}, volume={47}, ISSN={["1873-2291"]}, DOI={10.1016/j.polymer.2006.03.001}, abstractNote={Addition polymerization of norbornene-based monomers has been pursued toward the fabrication of photoresists for next-generation microlithography, using condensed carbon dioxide as the developing solvent. Addition polymers containing a norbornyl backbone, for dry plasma etch resistance and high thermal stability, were synthesized to include fluorinated moieties and chemical amplification switching groups. These materials have been characterized and their lithographic properties evaluated. Solubility differences between exposed and non-exposed resist have been observed in these novel systems, which should provide the necessary contrast for high-resolution imaging. Lithographic imaging produced dense lines as small as 3 μm.}, number={11}, journal={POLYMER}, author={Boggiano, Mary Kate and Vellenga, David and Carbonell, Ruben and Ashby, Valerie Sheares and DeSimone, Joseph M.}, year={2006}, month={May}, pages={4012–4017} } @article{olson_gratton_desimone_sheares_2006, title={Amorphous Linear Aliphatic Polyesters for the Facile Preparation of Tunable Rapidly Degrading Elastomeric Devices and Delivery Vectors}, volume={128}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja063092m}, DOI={10.1021/ja063092m}, abstractNote={A versatile method for preparing amorphous degradable elastomers with tunable properties that can be easily fabricated into a wide variety of shape-specific devices was investigated. Completely amorphous, liquid poly(ester ether) prepolymers with number-average molecular weights between 4 and 6 x 10(3) g/mol were prepared via condensation polymerization. These liquid prepolymers were then thermally cross-linked to form degradable elastomeric structures. The ability to vary the composition of these liquid prepolymers allows for easy control of the mechanical and degradation properties of the resulting elastomeric structures. Materials can be designed to completely degrade in vitro over a range of 30 days to 6 months, while the Young's modulus can be varied over 3 orders of magnitude (G = 0.02-20 MPa). Also, the liquid nature of these prepolymers makes them amenable to a wide variety of fabrication techniques. Using traditional and modified imprint lithography techniques, we have fabricated devices that demonstrate a wide variety of biologically applicable topologies, which could easily be extended to fabricate devices with more complex geometries. Until now, no method has combined this ease and speed of fabrication with the ability to control the mechanical and degradation properties of the resulting elastomers over such a broad range.}, number={41}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Olson, David A. and Gratton, Stephanie E. A. and DeSimone, Joseph M. and Sheares, Valerie V.}, year={2006}, month={Oct}, pages={13625–13633} } @article{yarbrough_rolland_desimone_callow_finlay_callow_2006, title={Contact angle analysis, surface dynamics, and biofouling characteristics of cross-linkable, random perfluoropolyether-based graft terpolymers}, volume={39}, ISSN={["1520-5835"]}, DOI={10.1021/ma0524777}, abstractNote={The conventional approach to prevention of marine biofouling has been the use of antifouling paints and coatings which function through the release of toxins in the immediate vicinity of the ship. Such technology, while admittedly effective, has proven to be responsible for an alarming increase in the levels of organotin and other toxic materials in and around dry docks, harbors, and shipping lanes which experience significant commercial and tourist traffic. Therefore, our objective is the rational design of minimally adhesive, mechanically stable, nontoxic fouling release coatings as responsible and practical alternatives to antifouling technologies. Herein we report on the synthesis and characterization of a series of cross-linkable perfluoropolyether (PFPE) graft terpolymers containing various alkyl (meth)acrylate monomers with glycidal methacrylate as the cure-site monomer. These materials were targeted for use as coatings to prevent marine biofouling. A series of terpolymers were prepared through application of the macromonomer approach, allowing for control of cross- link density, Tg, and modulus. Structure/property relationships were established through compositional variation with regard to the three classes of monomers. The first monomer class was an alkyl (meth)acrylate used to create the continuous phase of the microphase-separated graft terpolymers. Variation between methyl methacrylate (MMA) and n-butyl acrylate (BA) provided materials with a low (-10 °C) and a high (95 °C) Tg for the continuous phase. This was a means of isolating the effect of modulus and Tg on surface properties, while the basic chemical nature of the monomer remained unchanged. The second monomer class contained a curable functional group. Through incorporation of glycidyl methacrylate (GMA) in the monomer feed and manipulation of curing conditions, the relative effect of cross-link density on surface dynamics has been evaluated. The third monomer class was the PFPE macromonomer itself. The incorporation of this macromonomer was used to enhance the release properties of the resulting materials which relied on surface enrichment of the low surface energy PFPE component. Dynamic surface properties of these materials have been evaluated through dynamic surface tensiometry (DST). Herein, it has been demonstrated that contact angle hystersis can be significantly mitigated (i.e., ir is maximized) by as much as 50° through variation in bulk polymer composition, the chemical nature of monomers, cross-link density, modulus, and environmental conditions at the time of cure. The antifouling and fouling-release potential of the experimental coatings were also evaluated by laboratory assays employing the green fouling macroalga UlVa. The results from these initial studies suggest promising antifouling properties, especially with regard to spore settlement which was strongly inhibited on the experimental surfaces. Additionally, those that did settle were only weakly attached with one sample set exhibiting fairly moderate release of the young UlVa plants.}, number={7}, journal={MACROMOLECULES}, author={Yarbrough, JC and Rolland, JP and DeSimone, JM and Callow, ME and Finlay, JA and Callow, JA}, year={2006}, month={Apr}, pages={2521–2528} } @article{liu_desimone_roberts_2006, title={Cross-linking polymerization of acrylic acid in supercritical carbon dioxide}, volume={47}, ISSN={["0032-3861"]}, DOI={10.1016/j.polymer.2006.03.103}, abstractNote={Cross-linking polymerization of acrylic acid in supercritical carbon dioxide (scCO2) was studied in a batch reactor at 50 °C and 207 bar with either triallyl pentaerythritol ether or tetraallyl pentaerythritol ether as the cross-linker and with 2,2′-azobis(2,4-dimethyl-valeronitrile) as the free radical initiator. All polymers were white, dry, fine powders. Scanning electron microscopy showed that the morphology of the polymer particles was not affected by cross-linking. As the cross-linker concentration was increased, the polymer glass transition temperature first decreased, then increased. Water-soluble and water-insoluble polymers were synthesized by adjusting the cross-linker concentration. Viscosity measurements showed that the polymer thickening effect strongly depended on the degree of cross-linking. Finally, cross-linking polymerization of acrylic acid in scCO2 was carried out in a continuous stirred tank reactor. The use of cross-linker decreased the monomer conversion in this system.}, number={12}, journal={POLYMER}, author={Liu, Tao and DeSimone, Joseph M. and Roberts, George W.}, year={2006}, month={May}, pages={4276–4281} } @article{forbes_dukes_avdievich_harbron_desimone_2006, title={Flexible Biradicals in Liquid and Supercritical Carbon Dioxide:  The Exchange Interaction, the Chain Dynamics, and a Comparison with Conventional Solvents}, volume={110}, ISSN={1089-5639 1520-5215}, url={http://dx.doi.org/10.1021/jp053183q}, DOI={10.1021/jp053183q}, abstractNote={X-band time-resolved electron paramagnetic resonance (TREPR) spectra of three flexible biradicals of varying chain length and structure were obtained in liquid and supercritical carbon dioxide (CO2) solutions and compared to conventional solvents. For C16 acyl-alkyl biradical 1a, an average spin exchange interaction between the radical centers, J(avg), was obtained by spectral simulation using a simple model for spin-correlated radical pairs (SCRPs) and a small amount of T2 relaxation from a previously established J modulation mechanism. A large solvent effect on J(avg) was observed for the first time, varying by almost 1 order of magnitude from CO2 (J(avg) = -120 +/- 10 MHz) to heavy mineral oil (-11 +/- 3 MHz) for 1a. For C15 bis(alkyl) biradical 1b, spectra obtained under supercritical conditions are only slightly different from those detected in liquid CO2 but differ from spectra taken in benzene. For C10 acyl-alkyl biradical 2a, more emissive spin polarization due to S-T- mixing is observed in CO2 than in benzene. These results are discussed in terms of solvent properties such as dielectric constant, viscosity, and specific interactions. Both chain dynamics and changes to the equilibrium distribution of end-to-end distances can alter J(avg) and the observed ratio of S-T0 to S-T- mixing; however, faster chain dynamics is concluded to be the most likely cause of the observed effects in these systems.}, number={5}, journal={The Journal of Physical Chemistry A}, publisher={American Chemical Society (ACS)}, author={Forbes, Malcolm D. E. and Dukes, Katerina E. and Avdievich, Nikolai I. and Harbron, Elizabeth J. and DeSimone, Joseph M.}, year={2006}, month={Feb}, pages={1767–1774} } @article{euliss_dupont_gratton_desimone_2006, title={Imparting size, shape, and composition control of materials for nanomedicine}, volume={35}, ISSN={0306-0012 1460-4744}, url={http://dx.doi.org/10.1039/b600913c}, DOI={10.1039/b600913c}, abstractNote={This tutorial review presents an overview of strategies for the synthesis and fabrication of organic nanomaterials, specifically those with potential for use in medical applications. Examples include liposomes, micelles, polymer-drug conjugates and dendrimers. Methods of driving shape via"bottom-up" synthetic approaches and thermodynamics and kinetics are discussed. Furthermore, methods of driving shape via"top-down" physical and engineering techniques are also explored. Finally, a novel method (referred to as PRINT) used to produce nanoparticles that are shape-specific, can contain any cargo, and can be easily modified is examined along with its potential future role in nanomedicine.}, number={11}, journal={Chemical Society Reviews}, publisher={Royal Society of Chemistry (RSC)}, author={Euliss, Larken E. and DuPont, Julie A. and Gratton, Stephanie and DeSimone, Joseph}, year={2006}, pages={1095} } @article{liu_desimone_roberts_2006, title={Kinetics of the precipitation polymerization of acrylic acid in supercritical carbon dioxide: The locus of polymerization}, volume={61}, ISSN={["1873-4405"]}, DOI={10.1016/j.ces.2005.11.052}, abstractNote={The precipitation polymerization of acrylic acid (AA) has been carried out at 50 and 70∘C in supercritical carbon dioxide (scCO2), using a continuous stirred-tank reactor. Three kinetic models are compared with experimental data on the rate of polymerization and the viscosity-average molecular weight. The first model, the "solution polymerization" model, is based on the assumption that all reactions: initiation, propagation, and termination, take place in the fluid phase; no reaction takes place in the polymer phase. In the second model, the "surface polymerization" model, chain initiation is assumed to occur in the fluid phase, whereas chain propagation and termination occur in a thin zone on the surface of the polymer particles. The third model, the "interior polymerization" model, is similar to the "surface polymerization" model, except that chain propagation and chain termination take place uniformly throughout each polymer particle. Monomer is assumed to be in phase equilibrium between the supercritical fluid and the polymerization zone. The surface polymerization and interior polymerization models both provide a much better description of the experimental data than the solution polymerization model. This suggests that a significant portion of AA polymerization takes place in the polymer phase, when scCO2 is the reaction medium. However, the data do not support a choice between the surface and interior polymerization models.}, number={10}, journal={CHEMICAL ENGINEERING SCIENCE}, author={Liu, T and DeSimone, JM and Roberts, GW}, year={2006}, month={May}, pages={3129–3139} } @article{zhou_dominey_rolland_maynor_pandya_desimone_2006, title={Molded, high surface area polymer electrolyte membranes from cured liquid precursors}, volume={128}, ISSN={["0002-7863"]}, DOI={10.1021/ja064391e}, abstractNote={Polymer electrolyte membranes (PEMs) for fuel cells have been synthesized from easily processable, 100% curable, low molecular weight reactive liquid precursors that are photochemically cured into highly proton conductive solid membranes. The liquid precursors were directly cured into membranes of desired dimensions without the need for further processing steps such as melt extrusion or solvent casting. By employing chemical cross-linking, high proton conductivities can be achieved through the incorporation of significant levels of acidic groups without rendering the material water-soluble, which plagues commonly used non-cross-linked polymers. Fabrication of membrane electrode assemblies (MEAs) from these PEMs resulted in fuel cells that outperformed those based on commercial materials. Moreover, these liquid precursors enabled the formation of three-dimensional, patterned PEMs with high fidelity, micron-scale features by using soft lithographic/micromolding techniques. The patterned membranes provided a larger interfacial area between the membrane and catalyst layer than standard flat PEMs. MEAs composed of the patterned membranes demonstrated higher power densities over that of flat ones without an increase in the macroscopic area of the fuel cells. This can potentially miniaturize fuel cells and promote their application in portable devices.}, number={39}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Zhou, Zhilian and Dominey, Raymond N. and Rolland, Jason P. and Maynor, Benjamin W. and Pandya, Ashish A. and DeSimone, Joseph M.}, year={2006}, month={Oct}, pages={12963–12972} } @article{liu_garner_desimone_roberts_bothun_2006, title={Particle formation in precipitation polymerization: Continuous precipitation polymerization of acrylic acid in supercritical carbon dioxide}, volume={39}, ISSN={["0024-9297"]}, DOI={10.1021/ma061260p}, abstractNote={The morphology of the polymer produced during continuous precipitation polymerization of acrylic acid in supercritical carbon dioxide (scCO2) varied significantly with reaction conditions. Three different morphologies were observed:  a coagulum of primary particles with diameters of 100−200 nm, irregular particles with diameters of 5−20 μm, and spheres with diameters of 10−100 μm. To explore the variables that control particle morphology, the glass transition temperature (Tg) of poly(acrylic acid) (PAA) was measured at several CO2 pressures using high-pressure differential scanning calorimetry. Sorption of scCO2 into PAA also was measured at various temperatures and pressures with a quartz crystal microbalance. Chow's equation described the Tg reduction by CO2 quite accurately. Formation of large spherical particles of PAA was favored when the polymer molecular weight was relatively low and when the polymerization temperature was well above Tg.}, number={19}, journal={MACROMOLECULES}, author={Liu, Tao and Garner, Pamela and DeSimone, Joseph M. and Roberts, George W. and Bothun, Geoffrey D.}, year={2006}, month={Sep}, pages={6489–6494} } @article{ye_keiper_desimone_2006, title={Polymeric nanoparticles from supercritical CO2 microemulsion polymerization}, volume={24}, ISSN={["1439-6203"]}, DOI={10.1142/S0256767906001084}, abstractNote={Herein, we reported the microemulsion polymerization in supercritical carbon dioxide. With the aid of an anionic phosphate fluorosurfactant (bis-[2-(F-hexyl)ethyl]phosphate sodium), water-soluble/CO2-insoluble acryloxyethyltrimethyl ammonium chloride monomer and N,N′-methylene-bisacrylamide cross-linker were solubilized into CO2 continuous phase via the formation of water-in-CO2 (w/c) microemulsion water pools. Initiated by a CO2-soluble initiator, 2,2′-azo-bis-isobutyronitrile (AIBN), cross-linked poly(acryloxyethyltrimethyl ammonium chloride) particles were produced and stabilized in these w/c internal water pools. Nano-sized particles with sizes less than 20 nm in diameter and narrow particle size distributions were obtained.}, number={1}, journal={CHINESE JOURNAL OF POLYMER SCIENCE}, author={Ye, WJ and Keiper, JS and DeSimone, JM}, year={2006}, month={Jan}, pages={95–101} } @article{guo_andre_adam_panyukov_rubinstein_desimone_2006, title={Solution properties of a fluorinated alkyl methacrylate polymer in carbon dioxide}, volume={39}, ISSN={["1520-5835"]}, DOI={10.1021/ma052409k}, abstractNote={The solution properties of a fluorinated alkyl methacrylate, poly(1,1,2,2-tetrahydroperfluorooctyl methacrylate) (PFOMA), in liquid and supercritical carbon dioxide (CO2) were studied by static and dynamic light scattering. The solvent quality of CO 2 was found to improve with increasing temperature and CO2 density as exhibited by an increase of the second virial coefficient. Both the hydrodynamic radius expansion factor and the second virial coefficient of PFOMA solution were found to be functions of a single interaction parameter that can be independently changed by either temperature or density variations. Furthermore, we demonstrate that the relationship between two directly measurable quantities, the second virial coefficient and the hydrodynamic expansion ratio, is the same for both temperature-induced and CO2 density-induced variations of solvent quality.}, number={9}, journal={MACROMOLECULES}, author={Guo, J and Andre, P and Adam, M and Panyukov, S and Rubinstein, M and DeSimone, JM}, year={2006}, month={May}, pages={3427–3434} } @article{visintin_eichenlaub_portnow_carbonell_beaudoin_schauer_desimone_2006, title={Studies on CO2-based slurries and fluorinated silica and alumina particles for chemical mechanical polishing of copper films}, volume={153}, ISSN={["1945-7111"]}, DOI={10.1149/1.2358085}, abstractNote={The microelectronics industry has an interest in implementing condensed-CO 2 -based processes in many segments of the integrated-circuit manufacturing process. Preliminary studies of the behavior of copper surfaces and functionalized nanoparticles were performed in an attempt to offer insight into potential chemical mechanical planarization (CMP) and post-CMP cleaning applications using condensed CO 2 . Micrometer- and nanometer-sized silica particle surfaces were covalently modified with C 8 F 17 CH 2 CH 2 Si(CH 3 ) 2 Cl to give C 8 F 17 -silica, and alumina particle surfaces were modified with C 8 F 17 CH 2 CH 2 Si(OEt) 3 and C 8 F 17 COOH to yield C 8 F 17 -alumina and C 8 F 17 COOH-alumina. Atomic force microscopy was used to examine adhesion between these functionalized microparticles and a copper substrate under a nitrogen atmosphere. The adhesion force significantly decreased for the functionalized particles compared to the unmodified particles. In separate studies, copper was exposed to peroxide/ P-diketone solvents containing functionalized nanoparticles to investigate the effect of the nanoparticles on the copper dissolution rate. It was found that copper removal was proportional to the surface oxide and hydroxyl group concentration.}, number={12}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Visintin, Pamela M. and Eichenlaub, Sean K. and Portnow, Lauren E. and Carbonell, Ruben G. and Beaudoin, Stephen P. and Schauer, Cynthia K. and DeSimone, Joseph M.}, year={2006}, pages={G1064–G1071} } @article{zhang_zhou_cheng_desimone_samulski_2006, title={Superhydrophobic Behavior of a Perfluoropolyether Lotus-Leaf-like Topography}, volume={22}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la061400o}, DOI={10.1021/la061400o}, abstractNote={We demonstrate the fabrication of 2-D arrays of nanopillars made from perfluoropolyether derivatives using a porous anodic aluminum oxide membrane as a template. Pretexturing the aluminum prior to anodization enables one to engineer multiple morphological length scales and thereby synthesize a lotus-leaf-like topography. Both nanopillars on a flat surface and on a lotus-leaf-like topology exhibit superhydrophobicity, low contact angle hysteresis, and self-cleaning.}, number={20}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Zhang, Lei and Zhou, Zhilian and Cheng, Bin and DeSimone, Joseph M. and Samulski, Edward T.}, year={2006}, month={Sep}, pages={8576–8580} } @inbook{deyoung_romack_desimone_2002, place={Boston, MA}, series={Topics in Applied Chemistry}, title={Synthesis of Fluoropolymers in Liquid and Supercritical Carbon Dioxide Solvent Systems}, ISBN={0306460602}, url={http://dx.doi.org/10.1007/0-306-46918-9_13}, DOI={10.1007/0-306-46918-9_13}, abstractNote={Unlike a large portion of the many billions of pounds of organic and halogenated solvents used in industry every year, CO2 is inexpensive, of low toxicity, and environmentally and chemically benign. The prime factors inhibiting the widespread use of this attractive solvent replacement have been the disappointingly low solubility of most materials in CO2 in both liquid and supercritical states, and a less than complete understanding of its physical properties. Discoveries made over the past decade identifying the solubility of siloxanes and many amorphous fluoropolymers in CO2 have facilitated a greater understanding of the solvency properties of this uniquely "tunable" solvent. The subsequent development of amphiphilic surfactants incorporating lyophilic fluorocarbon or siloxane segments with lipophilic or hydrophilic moieties opens the door for the synthesis of a broad range of hydrocarbons. Carbon dioxide technology is of particular significance with respect to the manufacture of many fluoropolymers that require nonaqueous synthesis. Reduction of unwanted side reactions such as β-scission and opportunities for unique separation and purification processes demonstrate that CO2 is not only an adequate replacement for chlorofluorocarbons, but in many cases a superior one.}, booktitle={Fluoropolymers 1: Synthesis}, publisher={Kluwer Academic Publishers}, author={DeYoung, James P. and Romack, Timothy J. and DeSimone, Joseph M.}, editor={Hougham, G. and Cassidy, P.E. and Johns, K. and Davidson, T.Editors}, year={2002}, pages={191–205}, collection={Topics in Applied Chemistry} } @article{dunbar_omiatek_thai_kendrex_grotzinger_boyko_weinstein_skaf_bessel_denison_et al._2006, title={Use of substituted bis(acetylacetone) ethylenediimine and dialkyldithiocarbamate ligands for copper chelation in supercritical carbon dioxide}, volume={45}, ISSN={["0888-5885"]}, DOI={10.1021/ie060947v}, abstractNote={Chemical−mechanical planarization (CMP) is a process of oxidizing and chelating the copper overburden present in an interconnect device while mechanically polishing the surface of the wafer. Because the use of condensed CO2 as the solvent for CMP would be environmentally and technically advantageous, several substituted bis(acetylacetonate)ethylenediimine (R4BAE, where R = CH3 or CF3) and lithium or sodium dialkyldithiocarbamate (M+(R2DTC-), where M+ = Li+ or Na+ and R = ethyl, n-propyl, n-butyl, or 1,1,1-trifluoroethyl) ligands were used with t-butylperacetate (t-BuPA, as oxidant) for the oxidative dissolution of copper(0) in supercritical (sc) CO2 at 40 °C and 170−210 bar or in hexanes at 40 °C and atmospheric pressure. The reaction products from the copper etching were determined to be Cu(R4BAE) or Cu(R2DTC)2, respectively. The R2DTC- ligands had higher etch rates than the R4BAE ligands with comparable substituents, and the lithium dialkyldithiocarbamate salts gave higher copper etching rates than thei...}, number={26}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Dunbar, Andrew and Omiatek, Donna M. and Thai, Susan D. and Kendrex, Christopher E. and Grotzinger, Laurel L. and Boyko, Walter J. and Weinstein, Randy D. and Skaf, Dorothy W. and Bessel, Carol A. and Denison, Ginger M. and et al.}, year={2006}, month={Dec}, pages={8779–8787} } @article{young_desimone_2005, title={Advantages of supercritical carbon dioxide for composite particle synthesis using water-soluble or water-reactive monomers}, volume={38}, ISSN={["1520-5835"]}, DOI={10.1021/ma0478310}, abstractNote={Styrene (STY, Aldrich) and vinyl pyrrolidone (VP, Aldrich) were deinhibited by passage through an alumina column (Aldrich). Azobis(isobutyronitrile (AIBN, Aldrich) was recrystallized from methanol. Glycidyl methacrylate (GMA, Aldrich), isocyanatoethyl methacrylate (IEM, Aldrich), tetrahydrofuran (THF, Mallinckrodt), HPLC grade THF (Allied Signal), cyclohexane (Aldrich), deuterated methylene chloride (Cambridge), perfluorosolv (Fomblin PFS-1, Ausimont), and 0.5 % RuO4 aqueous solution (Polysciences, Inc) were used as received. Carbon dioxide (SFC/SFE grade) was kindly provided by Air Products and was used as received. PS-b-PFOA [MnPS = 6.6 kg/mol, MnPFOA = 53 kg/mol (6.6 K/53 K)] was synthesized by Betts.2 PS-b-PFOA (4.2 K/19.7 K) and PS-b-PFOA (4.2 K/37.5 K) were prepared by Shiho.3,4 Poly(hydroxyethyl methacrylate) (PHEMA) (with an average particle diameter, dn, of 0.26 μm and particle size distribution of 1.02 ) was synthesized by dispersion polymerization in supercritical CO2 using PS-b-PFOA (4.2 K/ 37.5 K) stabilizer by Shiho.4}, number={10}, journal={MACROMOLECULES}, author={Young, JL and DeSimone, JM}, year={2005}, month={May}, pages={4542–4544} } @article{visintin_carbonell_schauer_desimone_2005, title={Chemical functionalization of silica and alumina particles for dispersion in carbon dioxide}, volume={21}, ISSN={["0743-7463"]}, DOI={10.1021/la047823c}, abstractNote={The steric stabilization and flocculation of modified silica and alumina particle suspensions in condensed CO(2) were studied. Silica particles (average diameters of 7 and 12 nm) were functionalized using chlorosilanes of the form C(n)F(2n+1)CH(2)CH(2)Si(CH(3))(2)Cl (n = 8, 4, or 1) to give C(n)F(2n+1)-silica. Alumina particles (diameter of 8-14 nm) were grafted with C(8)F(17)CH(2)CH(2)Si(OEt)(3) and chemically modified with perfluorononanoic acid to yield C(8)F(17)-alumina and C(8)F(17)COOH-alumina, respectively. Elemental analysis and thermogravimetric analysis on the derivatized particles were carried out, and surface coverage was calculated. The stabilization of these modified particles in condensed CO(2) was quantified using turbidimetry. Particle stability was found to increase with increasing fluorinated tail length, temperature, and CO(2) density. Unmodified particles and those modified with only -CF(3) tails were unstable in condensed CO(2). Stabilization in supercritical CO(2) is continuous up to 24 h for the C(n)F(2n+1)-silica (n >/= 4) particles and 96 h for the C(8)F(17)-alumina particles. The C(8)F(17)COOH-alumina particles gave a significantly higher graft density than the C(8)F(17)-alumina particles but are not as stable in CO(2). The C(8)F(17)-alumina particles were stable at lower CO(2) densities than the modified silica particles. This stability difference may be attributed to the precursor organosilanes being monofunctional (modified silica) versus trifunctional (modified alumina), producing different structures on the surface.}, number={11}, journal={LANGMUIR}, author={Visintin, PM and Carbonell, RG and Schauer, CK and DeSimone, JM}, year={2005}, month={May}, pages={4816–4823} } @article{liu_desimone_roberts_2005, title={Continuous precipitation polymerization of acrylic acid in swercritical carbon dioxide: The polymerization rate and the polymer molecular weight}, volume={43}, ISSN={["1099-0518"]}, DOI={10.1002/pola.20728}, abstractNote={AbstractThe precipitation polymerization of acrylic acid in supercritical carbon dioxide was studied in a continuous stirred tank reactor with 2,2′‐azobis(2,4‐dimethylvaleronitrile) as the free‐radical initiator. The reactor temperature was between 50 and 90 °C, the pressure was 207 bar, and the average residence time was between 12 and 40 min. The product polymer was a white, dry, fine powder that dissolved in water. A wide range of polymer molecular weights (5–200 kg/mol) was obtained. The effects of the operating variables on the polymerization rate and on the polymer molecular weight were evaluated. The observed kinetics suggested that polymerization took place in both the supercritical fluid and the precipitated polymer particles. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2546–2555, 2005}, number={12}, journal={JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY}, author={Liu, T and Desimone, JM and Roberts, GW}, year={2005}, month={Jun}, pages={2546–2555} } @article{siripurapu_desimone_khan_spontak_2005, title={Controlled foaming of polymer films through restricted surface diffusion and the addition of nanosilica particles or CO2-philic surfactants}, volume={38}, ISSN={["1520-5835"]}, DOI={10.1021/ma047991b}, abstractNote={Synergistic use of surface barriers and nanoscale additives is investigated as alternate means by which to promote bubble nucleation in, and thus improve the porosity of, poly(methyl methacrylate) (PMMA) thin films (i) constrained between impenetrable plates, (ii) modified with either nanosilica particles, commercial short-chain fluorosurfactants, or designer CO2-philic block/graft copolymers, and (iii) exposed to high-pressure CO2. Resultant foamed films exhibit a vast array of micro/mesocellular morphologies in the presence of supercritical, as well as liquid, CO2 and demonstrate that copolymer micelles afford better control over bubble nucleation (with pore cell densities, N, approaching 1012 cells/cm3) relative to hard nonporous nanoparticles, which alone increase N by more than 2 orders of magnitude at low CO2 pressures. Incorporation of these nanoscale additives in a surface-constrained polymer matrix serves to enhance foaming through concurrent restriction of CO2 diffusion, heterogeneous nucleation...}, number={6}, journal={MACROMOLECULES}, author={Siripurapu, S and DeSimone, JM and Khan, SA and Spontak, RJ}, year={2005}, month={Mar}, pages={2271–2280} } @article{ahmed_desimone_roberts_2006, title={Copolymerization of vinylidene fluoride with hexafluoropropylene in supercritical carbon dioxide}, volume={39}, ISSN={["1520-5835"]}, DOI={10.1021/ma051268j}, abstractNote={Vinylidene fluoride (VDF) and hexafluoropropylene (HFP) were copolymerized in supercritical carbon dioxide (scCO2) by a free radical mechanism with and without the use of a fluorinated graft poly(methyl vinly ether-alt-maleic anhydride) copolymer (F-g-PMVE-MA) stabilizer. A series of VDF−HFP copolymers, with composition varying from 1.46 to 25.62 mol % (HFP in copolymer), were synthesized with yields in the range 25−54 wt %. The reactivity ratios of VDF and HFP in CO2 were estimated as rVDF = 5.13 and rHFP ≈ 0. The weight-average molecular weights of copolymers, relative to narrow standard poly(methyl methacrylate), were between 35 and 188 kg/mol, and the polydispersity was between 1.4 and 3.1. A solubility study demonstrated that VDF−HFP copolymers were more soluble in CO2 than in VDF or HFP. In addition, F-g-PMVE-MA was found to act as a stabilizer for the copolymerization of VDF and HFP in scCO2, leading to products with higher molecular weight and improved morphology.}, number={1}, journal={MACROMOLECULES}, author={Ahmed, TS and DeSimone, JM and Roberts, GW}, year={2006}, month={Jan}, pages={15–18} } @article{rolland_maynor_euliss_exner_denison_desimone_2005, title={Direct fabrication and harvesting of monodisperse, shape-specific nanobiomaterials}, volume={127}, ISSN={["1520-5126"]}, DOI={10.1021/ja051977c}, abstractNote={A versatile "top-down" method for the fabrication of particles, Particle Replication In Nonwetting Templates (PRINT), is described which affords absolute control over particle size, shape, and composition. This technique is versatile and general enough to fabricate particles with a variety of chemical structures, yet delicate enough to be compatible with sophisticated biological agents. Using PRINT, we have fabricated monodisperse particles of poly(ethylene glycol diacrylate), triacrylate resin, poly(lactic acid), and poly(pyrrole). Monodisperse particle populations, ranging from sub-200 nm nanoparticles to complex micron-scale objects, have been fabricated and harvested. PRINT uses low-surface energy, chemically resistant fluoropolymers as molding materials, which eliminates the formation of a residual interconnecting film between molded objects. Until now, the presence of this film has largely prevented particle fabrication using soft lithography. Importantly, we have demonstrated that PRINT affords the simple, straightforward encapsulation of a variety of important bioactive agents, including proteins, DNA, and small-molecule therapeutics, which indicates that PRINT can be used to fabricate next-generation particulate drug-delivery agents.}, number={28}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Rolland, JP and Maynor, BW and Euliss, LE and Exner, AE and Denison, GM and DeSimone, JM}, year={2005}, month={Jul}, pages={10096–10100} } @article{denison_evans_bessel_skaf_murray_desimone_2005, title={Electrochemical behavior of bis(beta-diketonate)copper complexes}, volume={152}, ISSN={["0013-4651"]}, DOI={10.1149/1.2047387}, abstractNote={The use of copper to produce interconnects for microchip manufacture has prompted a renewed interest in its corrosion, deposition, and passivation processes. The aqueous electrochemistry of four bis(β-diketonate)copper complexes (where β-diketone = acacH, tfacH, hfacH, and tmhdH) in aqueous media has been investigated. Equilibrium constants were used to calculate potential-pH diagrams, varying the β-diketone ligand, ligand and/or copper concentrations, and the ionic strength of the buffer solution. The theoretical potential-pH diagrams showed good correlation to the experimental data obtained in aqueous solutions.}, number={11}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Denison, GM and Evans, AO and Bessel, CA and Skaf, DW and Murray, RW and DeSimone, JM}, year={2005}, pages={B435–B440} } @article{ye_desimone_2005, title={Emulsion polymerization of N-ethylacrylamide in supercritical carbon dioxide}, volume={38}, ISSN={["1520-5835"]}, DOI={10.1021/ma048863q}, abstractNote={Herein, we report the emulsion polymerization of a water-soluble vinylic monomer in supercritical carbon dioxide. The water-soluble/CO2-insoluble monomer, N-ethylacrylamide, was effectively emulsified in CO2 continuous phase using an amphiphilic diblock copolymer consisting of a d-glucose-containing glycopolymer and a fluorinated block. The resulting high yield (>90%) of water-soluble poly(N-ethylacrylamide) was obtained in the form of a stable polymer colloid comprised of submicrometer-sized particles. The particle diameter and the distribution of sizes were shown to be influenced by various reaction parameters. Higher temperature and higher surfactant and initiator concentrations resulted in particles with smaller sizes. Two initiators, 2,2‘-azobisisobutyronitrile (AIBN) and a fluorinated azo-derivative, bis-[2-(F-octyl)ethyl]-4,4‘-azobis-4-cyanopentanoate, were used, and their thermal decomposition behaviors in supercritical CO2 were investigated. Compared with the AIBN-initiated system, the emulsion p...}, number={6}, journal={MACROMOLECULES}, author={Ye, WJ and DeSimone, JM}, year={2005}, month={Mar}, pages={2180–2190} } @article{liu_rolland_desimone_bard_2005, title={Fabrication of Ultramicroelectrodes Using A “Teflon-like” Coating Material}, volume={77}, ISSN={0003-2700 1520-6882}, url={http://dx.doi.org/10.1021/ac0482918}, DOI={10.1021/ac0482918}, abstractNote={A new method was developed for the preparation of ultramicroelectrodes (UMEs). In this method, a photo-curable fluorinated functionalized perfluoropolyether, a liquid v-like polymer at room temperature, is used as the material for the insulation of metal microwires or carbon fibers. The UMEs prepared by this method were usually conical shaped and could be used both in aqueous solutions and with aprotic solvents. The relatively small thicknesses of the insulating sheath of the "Teflon-like"UME tips make them particularly useful for scanning electrochemical microscopy measurements.}, number={9}, journal={Analytical Chemistry}, publisher={American Chemical Society (ACS)}, author={Liu, Biao and Rolland, Jason P. and DeSimone, Joseph M. and Bard, Allen J.}, year={2005}, month={May}, pages={3013–3017} } @article{kennedy_roberts_desimone_2005, title={Heterogeneous polymerization of fluoroolefins in supercritical carbon dioxide}, volume={175}, ISBN={["3-540-22923-X"]}, ISSN={["1436-5030"]}, DOI={10.1007/b100114}, abstractNote={In recent years, carbon dioxide has been investigated for its potential to replace the aqueous and organic solvents used in polymerization processes. Carbon dioxide has several benefits, including being environmentally benign, a tunable solvent, resistant to chain transfer, and of low viscosity which facilitates high initiator efficiencies and fluid handling. Homo- and copolymerization of fluoroolefins such as tetrafluoroethylene (TFE), vinylidene fluoride (VF2), hexafluoropropylene (HFP), and perfluorinated vinyl ethers in carbon dioxide are particularly interesting because of the significant waste reduction and the elimination of potentially harmful processing agents. This review focuses on recent developments in polymerizing fluoroolefins via heterogeneous polymerization in carbon dioxide. At least one CO2-based polymerization process has recently been commercialized, and additional research is underway to understand the kinetics associated with polymerizing fluoroolefins in carbon dioxide. As researchers improve their understanding of CO2-based polymerizations, and as industry continues to look for more economically and environmentally-sound alternatives to existing processes, it will become more and more common to employ carbon dioxide as a polymerization medium.}, journal={POLYMER PARTICLES}, author={Kennedy, KA and Roberts, GW and DeSimone, JM}, year={2005}, pages={329–346} } @article{dickson_smith_dhanuka_srinivasan_stone_rossky_behles_keiper_xu_johnson_et al._2005, title={Interfacial Properties of Fluorocarbon and Hydrocarbon Phosphate Surfactants at the Water−CO2Interface}, volume={44}, ISSN={0888-5885 1520-5045}, url={http://dx.doi.org/10.1021/ie048999c}, DOI={10.1021/ie048999c}, abstractNote={With high-pressure pendant-drop tensiometry, the interfacial tension (γ) and surface excess (Γ∞) for a family of ionic surfactants with identical phosphate headgroups and varying fluorocarbon and hydrocarbon tail structures were examined at the water−CO2 interface. To compensate for the unusually weak CO2−surfactant tail interactions, we designed hydrocarbon tails with weak tail−tail interactions to achieve a more favorable hydrophilic−CO2-philic balance. Branching of hydrocarbon surfactant tails is shown to lead to more favorable adsorption at the interface, closer to that of fluorocarbon surfactants. γ for a double-tail hydrocarbon phosphate surfactant with a relatively high degree of tail branching was lowered from the water−CO2 binary interface value of about 20 mN/m at 25 °C and 340 bar to 3.7 mN/m. This reduction in γ is attributed to both a decrease in the free volume between tails at the interface and reduced tail−tail interactions. In addition to tail structure, the effects of surfactant counteri...}, number={5}, journal={Industrial & Engineering Chemistry Research}, publisher={American Chemical Society (ACS)}, author={Dickson, Jasper L. and Smith, P. Griffin and Dhanuka, Varun V. and Srinivasan, Vibha and Stone, Matthew T. and Rossky, Peter J. and Behles, Jacqueline A. and Keiper, Jason S. and Xu, Bin and Johnson, Charles and et al.}, year={2005}, month={Mar}, pages={1370–1380} } @article{xu_lynn_guo_melnichenko_wignall_mcclain_desimone_johnson_2005, title={NMR and SANS studies of aggregation and microemulsion formation by phosphorus fluorosurfactants in liquid and supercritical carbon dioxide}, volume={109}, ISSN={["1520-6106"]}, DOI={10.1021/jp0580322}, abstractNote={(1)H NMR relaxation and diffusion studies were performed on water-in-CO(2) (W/C) microemulsion systems formed with phosphorus fluorosurfactants of bis[2-(F-hexyl)ethyl] phosphate salts (DiF(8)), having different counterions (Na(+), NH(4)(+), N(CH(3))(4)(+)) by means of high-pressure in situ NMR. Water has a low solubility in CO(2) and is mainly solubilized by the microemulsion droplets formed with surfactants added to CO(2) and water mixtures. There is rapid exchange of water between the bulk CO(2) and the microemulsion droplets; however, NMR relaxation measurements show that the entrapped water has restricted motion, and there is little "free" water in the core. Counterions entrapped by the droplets are mostly associated with the surfactant headgroups: diffusion measurements show that counterions and the surfactant molecules move together with a diffusion coefficient that is associated with the droplet. The outer shell of the microemulsion droplets consists of the surfactant tails with some associated CO(2). For W/C microemulsions formed with the phosphate-based surfactant having the ammonia counterion (A-DiF(8)), the (1)H NMR signal for NH(4)(+) shows a much larger diffusion coefficient than that of the surfactant tails. This apparent paradox is explained on the basis of proton exchange between water and the ammonium ion. The observed dependence of the relaxation time (T(2)) on W(0) (mole ratio of water to surfactant in the droplets) for water and NH(4)(+) can also be explained by this exchange model. The average hydrodynamic radius of A-DiF(8) microemulsion droplets estimated from NMR diffusion measurements (25 degrees C, 206 bar, W(0) = 5) was R(h) = 2.0 nm. Assuming the theoretical ratio of R(g)/R(h) = 0.775 for a solid sphere, where R(g) is the radius of gyration, the equivalent hydrodynamic radius from SANS is R(h) = 1.87 nm. The radii measured by the two techniques are in reasonable agreement, as the two techniques are weighted to measure somewhat different parts of the micelle structure.}, number={20}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Xu, B and Lynn, GW and Guo, J and Melnichenko, YB and Wignall, GD and McClain, JB and DeSimone, JM and Johnson, CS}, year={2005}, month={May}, pages={10261–10269} } @inbook{wood_yarbrough_roberts_desimone_2006, title={Production of Fluoropolymers in Supercritical Carbon Dioxide}, ISBN={9783527606726 9783527310920}, url={http://dx.doi.org/10.1002/3527606726.ch9}, DOI={10.1002/3527606726.ch9}, booktitle={Supercritical Carbon Dioxide}, publisher={Wiley-VCH Verlag GmbH & Co. KGaA}, author={Wood, Colin D. and Yarbrough, Jason C. and Roberts, George and DeSimone, Joseph}, year={2006}, month={Mar}, pages={189–204} } @article{kiserow_shi_roberts_gross_desimone_2005, title={Solid-state polymerization of poly(bisphenol A carbonate) facilitated by supercritical carbon dioxide}, volume={898}, ISBN={["0-8412-3887-1"]}, ISSN={["0097-6156"]}, DOI={10.1021/bk-2005-0898.ch007}, abstractNote={During the solid state polymerization (SSP) of poly(bisphenol A carbonate), both the forward reaction rate constant and the phenol diffusion coefficient inside the polymer particle were significantly higher when SSP was carried out in supercritical carbon dioxide (scCO 2 ) compared to in atmospheric N 2 . These enhancements depended on the reaction conditions, and can be understood in terms of the CO 2 concentrations in the polymer. Polymer with a M w as high as 78100 has been synthesized by SSP with scCO 2 as the sweep fluid.}, journal={ADVANCES IN POLYCARBONATES}, author={Kiserow, DJ and Shi, CM and Roberts, GW and Gross, SM and DeSimone, JM}, year={2005}, pages={86–94} } @article{kim_novick_desimone_carbonell_2006, title={Ultrathin film deposition by liquid CO2 free meniscus coating-uniformity and morphology}, volume={22}, ISSN={["0743-7463"]}, DOI={10.1021/la0521600}, abstractNote={Ultrathin organic films of sucrose octaacetate (SOA) were deposited on 12.5 cm diameter silicon wafer substrates using high-pressure free meniscus coating (hFMC) with liquid CO2 (l-CO2) as a coating solvent. The dry film thickness across the wafer and the morphology of deposited films were characterized as a function of coating conditions-withdrawal velocity, solution concentration, and evaporation driving force (deltaP). When no evaporation driving force was applied (deltaP = 0), highly uniform films were deposited with thickness in the range of 8-105 angstroms over the entire concentration range (3-11 wt%). Uniform films were also obtained at low concentrations (3-5 wt%) with a low evaporation driving force (deltaP = 0.0138 MPa). However, films deposited at medium to high concentrations (7-11 wt%) were thicker (110-570 angstroms) and less uniform, with larger nonuniformities at higher applied evaporation driving forces. Optical microscopy and atomic force microscopy (AFM) were used to characterize film morphology including drying defects and film roughness. Films deposited without evaporation had no apparent drying defects and very low root-mean-square (RMS) roughness (1.4-3.8 angstroms). Spinodal-like dewetting morphologies including holes with diameters in the range of 100-300 nm, and surface undulations were observed in films deposited at medium concentration (7 wt%) and low deltaP (0.0138-0.0276 MPa). At higher concentrations and higher evaporative driving forces, spinodal-like dewetting morphologies disappeared but concentric ring defect structures were observed with diameters in the range 20-125 microm. The film thickness and morphology of SOA films deposited from 1-CO2 hFMC were compared to those deposited from toluene and acetone under normal dip coating. Films deposited from l-CO2 hFMC were much thinner, more uniform, and exhibited much fewer drying defects and lower RMS roughness.}, number={2}, journal={LANGMUIR}, author={Kim, J and Novick, BJ and DeSimone, JM and Carbonell, RG}, year={2006}, month={Jan}, pages={642–657} } @article{hoggan_wang_flowers_desimone_carbonell_2004, title={"dry" lithography using liquid and supercritical carbon dioxide based chemistries and processes}, volume={17}, ISSN={["1558-2345"]}, DOI={10.1109/tsm.2004.837002}, abstractNote={Novel carbon dioxide (CO/sub 2/) soluble photoresists were synthesized based on random copolymers of 1,1-dihydroperfluorooctylmethacrylate and 2-tetrahyrdopyranyl methacrylate. These resins, along with specially designed CO/sub 2/-soluble photoacid generators, were utilized to demonstrate the potential for a new "dry" lithographic process. Photoresist spin casting, development, and stripping were all carried out using only liquid and supercritical CO/sub 2/ as the processing medium. A novel high-pressure spin coating process was used to deposit the photoresist films. Parameters such as resist sensitivity, contrast, and resolution were investigated. Wafers were imaged using both 248and 193-nm radiation, demonstrating the potential of this new photoresist platform for use as a sustainable technology for the microelectronics industry.}, number={4}, journal={IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING}, author={Hoggan, EN and Wang, K and Flowers, D and DeSimone, JM and Carbonell, RG}, year={2004}, month={Nov}, pages={510–516} } @misc{jones_zweber_deyoung_mcclain_carbonell_desimone_2004, title={Applications of "dry" processing in the microelectronics industry using carbon dioxide}, volume={29}, ISSN={["1547-6561"]}, DOI={10.1080/10408430490888968}, abstractNote={ABSTRACT Condensed carbon dioxide (CO2) has emerged as a leading enabler of advanced semiconductor manufacturing processes. By exploiting the physical properties of CO2, some of the current challenges encountered in microelectronics processing related to shrinking feature sizes and materials compatibility have been addressed. Furthermore, the potential for reduction of chemicals used in processing is realized. Applications of CO2 in microelectronics operations such as wafer cleaning, spin-coating, development, and stripping of photoresists, drying, low-k film preparation and repair, etching, and metal deposition are discussed.}, number={3-4}, journal={CRITICAL REVIEWS IN SOLID STATE AND MATERIALS SCIENCES}, author={Jones, CA and Zweber, A and DeYoung, JP and McClain, JB and Carbonell, R and DeSimone, JM}, year={2004}, pages={97–109} } @misc{desimone_carbonell_kendall_mcadams_2004, title={CO2-processes photoresists, polymers, and photoactive compounds for microlithography}, volume={6,764,809}, number={2004 July 20}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carbonell, R. G. and Kendall, J. and McAdams, C. L.}, year={2004}, month={Jul} } @misc{desimone_birnbaum_carbonell_crette_mcclain_mccleskey_powell_romack_tumas_2004, title={Carbon dioxide-soluble polymers and swellable polymers for carbon dioxide applications}, volume={6,747,179}, number={2004 June 8}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Birnbaum, Eva and Carbonell, Ruben G. and Crette, Stephanie and McClain, James B. and McCleskey, T. Mark and Powell, Kimberly R. and Romack, Timothy J. and Tumas, William}, year={2004}, month={Jun} } @article{ahmed_desimone_roberts_2004, title={Continuous precipitation polymerization of vinylidene fluoride in supercritical carbon dioxide: modeling the molecular weight distribution}, volume={59}, ISSN={0009-2509}, url={http://dx.doi.org/10.1016/j.ces.2004.07.078}, DOI={10.1016/j.ces.2004.07.078}, abstractNote={The molecular weight distribution (MWD) of poly(vinylidene fluoride) synthesized continuously in supercritical carbon dioxide is bimodal under some circumstances. A homogeneous model that can account for this bimodality is presented in this paper. The model takes into account the decrease in the mobility of polymeric radicals as they grow in size. This decrease in mobility impacts the rates of the termination reactions. The model, although simple, can describe many features of the experimental MWDs. For example as monomer concentration increases, the MWD changes from unimodal to bimodal, the second peak increases in size at the expense of the first one, and the peaks shift to higher molecular weights. In addition, the model can describe the effect of residence time on the MWD for both low and high monomer concentration. Finally, the effect of temperature on the MWD can be described fairly well using only one adjustable parameter.}, number={22-23}, journal={Chemical Engineering Science}, publisher={Elsevier BV}, author={Ahmed, Tamer S. and DeSimone, Joseph M. and Roberts, George W.}, year={2004}, month={Nov}, pages={5139–5144} } @misc{wood_cooper_desimone_2004, title={Green synthesis of polymers using supercritical carbon dioxide}, volume={8}, ISSN={["1879-0348"]}, DOI={10.1016/j.cossms.2005.02.001}, abstractNote={Supercritical carbon dioxide is the most extensively studied supercritical fluid (SCF) medium for polymerization reactions and organic transformations. This can be attributed to a list of advantages ranging from solvent properties to practical environmental as well as economic considerations. Aside from these gains, CO2 finds particularly advantageous application in the synthesis and processing of fluoropolymers and porous materials and as such, this will be the subject of this review. The overall aim is to highlight areas where the unique properties of SCF solvents can be exploited to generate polymers that would be difficult or inconvenient to obtain by other routes.}, number={5}, journal={CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE}, author={Wood, CD and Cooper, AI and DeSimone, JM}, year={2004}, month={Oct}, pages={325–331} } @article{rolland_hagberg_denison_carter_desimone_2004, title={High-resolution soft lithography: Enabling materials for nanotechnologies}, volume={43}, ISSN={["1433-7851"]}, DOI={10.1002/anie.200461122}, abstractNote={The availability of commercially viable nanofabrication processes is key to realizing the potential of nanotechnologies, especially in the fields of photonics, electronics, and proteomics. The imprint lithographic (IL) technique is a case in point, an alternative to photolithography for manufacturing integrated circuits, nanofluidic and other devices with sub100-nm features. However, it is becoming increasingly clear that new materials are needed to advance IL methods to their putative limits. We recently reported the fabrication of organic-solvent resistant, microfluidic devices with features on the order of hundreds of microns made from photocurable perfluoropolyethers (PFPEs). PFPE-based materials are liquids at room temperature and can be photochemically cross-linked to yield highly fluorinated, solvent resistant, chemically robust, durable, elastomers with a modulus of 4.0 MPa. Herein we report the successful use of PFPE-based materials in high-resolution imprint lithography. Imprint lithography can be roughly broken into two areas: 1) so-called soft lithographic techniques, such as solventassisted micro-molding (SAMIM), micro-molding in capillaries (MIMIC), and microcontact printing (MCP), and 2) rigid imprint techniques, such as nanocontact molding (NCM), “step and flash” imprint lithography (S-FIL), and nanoimprint lithography (NIL). Polydimethylsiloxane (PDMS)}, number={43}, journal={ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, author={Rolland, JP and Hagberg, EC and Denison, GM and Carter, KR and DeSimone, JM}, year={2004}, pages={5796–5799} } @article{andre_folk_adam_rubinstein_desimone_2004, title={Light scattering study of polydimethyl siloxane in liquid and supercritical carbon dioxide}, volume={108}, ISSN={["1089-5639"]}, DOI={10.1021/jp0481308}, abstractNote={In this paper, we report the results of static and dynamic light scattering investigations of polydimethyl siloxane (PDMS) solutions in both liquid and supercritical carbon dioxide (CO2). This study was performed below the theta point and provides quantitative information on the CO2 solvent quality over a large range of temperature (25−54 °C) and density (0.97−1.01 g/mL). The solvent quality of the CO2 can be adjusted by independently varying temperature or density, as demonstrated by the dependence of the second virial coefficient on these two parameters. The theta temperature was observed to be a strong function of CO2 density and may be a weak function of the PDMS molecular weight. The strength of the excluded volume interactions in the PDMS−CO2 solution was determined to be weaker than predicted, and no universal behavior was observed.}, number={45}, journal={JOURNAL OF PHYSICAL CHEMISTRY A}, author={Andre, P and Folk, SL and Adam, M and Rubinstein, M and DeSimone, JM}, year={2004}, month={Nov}, pages={9901–9907} } @article{siripurapu_desimone_khan_spontak_2004, title={Low-temperature, surface-mediated foaming of polymer films}, volume={16}, ISSN={["1521-4095"]}, DOI={10.1002/adma.200306068}, abstractNote={Ultraporous thin polymer films (see Figure) are generated using physical constraints imposed by external surfaces (hard plates) and internal surfaces (hard nanoparticles and soft micelles) via foaming with supercritical CO2. The constraints serve as diffusion barriers and/or heterogeneous nucleation sites. Use of CO2‐philic copolymers further enables microcellular foaming at reduced pressures with liquid CO2.}, number={12}, journal={ADVANCED MATERIALS}, author={Siripurapu, S and DeSimone, JM and Khan, SA and Spontak, RJ}, year={2004}, month={Jun}, pages={989-+} } @article{lacroix-desmazes_andre_desimone_ruzette_boutevin_2004, title={Macromolecular surfactants for supercritical carbon dioxide applications: Synthesis and characterization of fluorinated block copolymers prepared by nitroxide-mediated radical polymerization}, volume={42}, ISSN={0887-624X 1099-0518}, url={http://dx.doi.org/10.1002/pola.20193}, DOI={10.1002/pola.20193}, abstractNote={AbstractPoly(perfluorooctyl‐ethylenoxymethylstyrene) (PFDS) and poly(1,1,2,2‐tetrahydroperfluorodecyl acrylate) (PFDA) homopolymers as well as poly(styrene)‐b‐poly(perfluorooctyl‐ethylenoxymethylstyrene) (PS‐b‐PFDS) and poly(styrene)‐b‐poly(1,1,2,2‐tetrahydroperfluorodecyl acrylate) acrylate) (PS‐b‐PFDA) block copolymers of various chain lengths were synthesized by nitroxide‐mediated radical polymerization in the presence of either 2,2,6,6‐tetramethyl‐1‐piperidinyloxy free radical (TEMPO) in the case of FDS monomer or N‐tert‐butyl‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl)‐N‐oxyl (DEPN) in the case of the FDA monomer. The molar composition of the block copolymers was determined by elemental analysis and proton NMR while the blocky structure was checked by SEC analysis in trifluorotoluene. Block copolymers PS‐b‐PFDS (3.6K/60K) and PS‐b‐PFDA (3.7K/43K) were soluble in neat CO2 at moderate pressure and temperature, indicating the formation of micelles. Similar block copolymers with a longer PS block such as PS‐b‐PFDA (9.5K/49K), corresponding to a lower CO2‐philic/CO2‐phobic balance, were insoluble in neat CO2 but could be solubilized in the presence of styrene as a cosolvent. Additionally, surface and bulk properties of PS‐b‐PFDA were investigated, indicating the same surface tension as for the PFDA homopolymer (γLV = 10.3 mN/m) and a bulk nanostructured morphology. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3537–3552, 2004}, number={14}, journal={Journal of Polymer Science Part A: Polymer Chemistry}, publisher={Wiley}, author={Lacroix-Desmazes, Patrick and Andre, Pascal and Desimone, Joseph M. and Ruzette, Anne-Val�rie and Boutevin, Bernard}, year={2004}, pages={3537–3552} } @misc{desimone_khan_royer_spontak_walker_gay_siripurapu_2004, title={Methods of making foamed materials of blended thermoplastic polymers using carbon dioxide}, volume={6,790,870}, number={2004 Sept. 14}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Khan, S. A. and Royer, J. R. and Spontak, R. J. and Walker, T. A. and Gay, Y. J. and Siripurapu, S.}, year={2004} } @article{paisner_desimone_2004, title={Micro- and nanoporous materials developed using Supercritical CO2 - Novel synthetic methods for the development of micro- and nanoporous materials toward microelectronic applications}, volume={874}, DOI={10.1021/bk-2004-0874.ch017}, abstractNote={A number of different types of nanoporous materials for use in low dielectric constant applications have been developed in recent years, including nanoporous silica, polyimides, poly(arylethers), and poly(methyl silsesquioxanes). Recently, much research has been done in the field of supercritical carbon dioxide (scCO2) and its use in the synthesis of polymers for microelectronic applications. A variety of different methods using supercritical CO2 to form micro- and nanoporous materials towards applications in the microelectronic industry are described.}, number={2004}, journal={ACS Symposium Series}, author={Paisner, S. N. and Desimone, J. M.}, year={2004}, pages={223–235} } @misc{desimone_roberts_charpentier_2004, title={Multimodal fluoropolymers and methods of making the same}, volume={6,716,945}, number={2004 Apr. 6}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Roberts, G. W. and Charpentier, P. A.}, year={2004}, month={Apr} } @article{wood_michel_rolland_desimone_2004, title={New fluoropolymer materials}, volume={125}, ISSN={["1873-3328"]}, DOI={10.1016/j.jfluchem.2004.09.029}, abstractNote={We report the synthesis of two classes of fluoropolymers that could impact several key lithographic techniques; one has potential applications in next generation photolithography (193 nm, 157 nm, and immersion lithography) and the other in lithographic techniques which are emerging as viable alternatives to photolithography for future applications (i.e., soft lithography).}, number={11}, journal={JOURNAL OF FLUORINE CHEMISTRY}, author={Wood, CD and Michel, U and Rolland, JP and DeSimone, JA}, year={2004}, month={Nov}, pages={1671–1676} } @article{visintin_bessel_white_schauer_desimone_2005, title={Oxidative dissolution of copper and zinc metal in carbon dioxide with tert-butyl peracetate and a beta-diketone chelating agent}, volume={44}, ISSN={["1520-510X"]}, DOI={10.1021/ic049765o}, abstractNote={A series of beta-diketone ligands, R(1)COCH(2)COR(2) [tmhdH (R(1) = R(2) = C(CH(3))(3)); tfacH (R(1) = CF(3); R(2) = CH(3)); hfacH (R(1) = R(2) = CF(3))], in combination with tert-butyl peracetate (t-BuPA), have been investigated as etchant solutions for dissolution of copper metal into carbon dioxide solvent. Copper removal in CO(2) increases in the order tfacH < tmhdH < hfacH. A study of the reactions of the hfacH/t-BuPA etchant solution with metallic copper and zinc was conducted in three solvents: scCO(2) (supercrical CO(2)); hexanes; CD(2)Cl(2). The etchant solution/metallic zinc reaction produced a diamagnetic Zn(II) complex, which allowed NMR identification of the t-BuPA decomposition products as tert-butyl alcohol and acetic acid. Gravimetric analysis of the amount of zinc consumed, together with NMR studies, confirmed the 1:1:2 Zn:t-BuPA:hfacH reaction stoichiometry, showing t-BuPA to be an overall two-electron oxidant for Zn(0). The metal-containing products of the copper and zinc reactions were characterized by elemental analysis, IR spectroscopy, and, as appropriate, NMR spectroscopy and single-crystal X-ray diffraction [trans-M(hfac)(2)(H(2)O)(CH(3)CO(2)H) (1, M = Cu; 2, M = Zn)]. On the basis of the experimental results, a working model of the oxidative dissolution reaction is proposed, which delineates the key chemical variables in the etching reaction. These t-BuPA/hfacH etchant solutions may find application in a CO(2)-based chemical mechanical planarization (CMP) process.}, number={2}, journal={INORGANIC CHEMISTRY}, author={Visintin, PM and Bessel, CA and White, PS and Schauer, CK and DeSimone, JM}, year={2005}, month={Jan}, pages={316–324} } @misc{desimone_keiper_2004, title={Phosphate fluorosurfactants for use in carbon dioxide}, volume={6,684,525}, number={2004 Feb. 3}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Keiper, J. S.}, year={2004}, month={Feb} } @article{keiper_behles_bucholz_simhan_desimone_lynn_wignall_melnichenko_frielinghaus_2004, title={Self-assembly of phosphate fluorosurfactants in carbon dioxide}, volume={20}, ISSN={["0743-7463"]}, DOI={10.1021/la034742s}, abstractNote={Anionic phosphodiester surfactants, possessing either two fluorinated chains (F/F) or one hydrocarbon chain and one fluorinated chain (H/F), were synthesized and evaluated for solubility and self-assembly in liquid and supercritical carbon dioxide. Several surfactants, of both F/F and H/F types and having varied counterions, were found to be capable of solubilizing water-in-CO2 (W/C), via the formation of microemulsions, expanding upon the family of phosphate fluorosurfactants already found to stabilize W/C microemulsions. Small-angle neutron scatteringwas used to directly characterize the microemulsion particles at varied temperatures, pressures, and water loadings, revealing behavior consistent with previous results on W/C microemulsions.}, number={4}, journal={LANGMUIR}, author={Keiper, JS and Behles, JA and Bucholz, TL and Simhan, R and DeSimone, JM and Lynn, GW and Wignall, GD and Melnichenko, YB and Frielinghaus, H}, year={2004}, month={Feb}, pages={1065–1072} } @article{rolland_van dam_schorzman_quake_desimone_2004, title={Solvent-resistant photocurable "liquid teflon" for microfluidic device fabrication}, volume={126}, ISSN={["0002-7863"]}, DOI={10.1021/ja031657y}, abstractNote={We report the first fabrication of a solvent-compatible microfluidic device based on photocurable “Liquid Teflon” materials. The materials are highly fluorinated functionalized perfluoropolyethers (PFPEs) that have liquidlike viscosities that can be cured into tough, highly durable elastomers that exhibit the remarkable chemical resistance of fluoropolymers such as Teflon. Poly(dimethylsiloxane) (PDMS) elastomers have rapidly become the material of choice for many recent microfluidic device applications. Despite the advantages of PDMS in relation to microfluidics technology, the material suffers from a serious drawback in that it swells in most organic solvents. The swelling of PDMS-based devices in organic solvents greatly disrupts the micrometer-sized features and makes it impossible for fluids to flow inside the channels. Our approach to this problem has been to replace PDMS with photocurable perfluoropolyethers. Device fabrication and valve actuation were accomplished using established procedures for ...}, number={8}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Rolland, JP and Van Dam, RM and Schorzman, DA and Quake, SR and DeSimone, JM}, year={2004}, month={Mar}, pages={2322–2323} } @article{hoggan_flowers_wang_desimone_carbonell_2004, title={Spin coating of photoresists using liquid carbon dioxide}, volume={43}, ISSN={["0888-5885"]}, DOI={10.1021/ie0308543}, abstractNote={A novel high-pressure carbon dioxide (CO2) spin-coating apparatus was designed and constructed to produce high-quality thin films of CO2-soluble photoresists based on 1H,1H-perfluorooctyl methacrylate/tert-butyl methacrylate copolymers. Film thicknesses were correlated to various process variables including rotational speed, solution viscosity, and evaporative driving force. The effects of these operating conditions on the film thickness and uniformity were compared to those of a theoretical model adapted for spin coating in CO2. Excellent correlation was found between the theoretical predictions and observed film properties, with the final films being of sufficient quality for use in photolithography. The potential of this spin-coating process in CO2 for developing a novel “dry lithography” is discussed.}, number={9}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Hoggan, EN and Flowers, D and Wang, K and DeSimone, JM and Carbonell, RG}, year={2004}, month={Apr}, pages={2113–2122} } @article{lo celso_triolo_triolo_thiyagarajan_amenitsch_steinhart_kriechbaum_desimone_triolo_2003, title={A combined small-angle neutron and X-ray scattering study of block copolymers micellisation in supercritical carbon dioxide}, volume={36}, ISSN={0021-8898}, url={http://dx.doi.org/10.1107/s0021889803003959}, DOI={10.1107/s0021889803003959}, abstractNote={Small angle neutron and X-ray scattering (SANS and SAXS) are used to investigate the monomer–aggregate transition of fluorocarbon–hydrocarbon diblock copolymers in supercritical carbon dioxide. SANS data are analyzed using a polydisperse sphere core–shell model. Synchrotron SAXS data have been collected by profiling the pressure at different temperatures, and critical micellization densities have been obtained for a series of diblock solutions. Finally pressure jump experiments, combined with synchrotron SAXS, have revealed two steps in the dynamics of the formation of the aggregates.}, number={3}, journal={Journal of Applied Crystallography}, publisher={International Union of Crystallography (IUCr)}, author={Lo Celso, Fabrizio and Triolo, Alessandro and Triolo, Fabio and Thiyagarajan, Pappannan and Amenitsch, Heinz and Steinhart, Milos and Kriechbaum, Manfred and DeSimone, Joseph M. and Triolo, Roberto}, year={2003}, month={Apr}, pages={660–663} } @misc{carbonell_desimone_novick_2003, title={Apparatus for meniscus coating with liquid carbon dioxide}, volume={6,517,633}, number={2003 Feb 11}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M. and Novick, B. J.}, year={2003}, month={Feb} } @article{michel_resnick_kipp_desimone_2003, title={Copolymerization of tetrafluoroethylene and 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole in Supercritical carbon dioxide}, volume={36}, ISSN={["1520-5835"]}, DOI={10.1021/ma0344240}, abstractNote={Copolymers of tetrafluoroethylene (TFE) and 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole (PDD) were synthesized in carbon dioxide at low temperatures. Bis(perfluoro-2-N-propoxypropionyl) peroxide was used as initiator. A range of copolymers with various compositions and different molecular weights were prepared in yields as high as 74%. The glass transition temperature of the copolymers increased with increasing PDD content and ranged from 67 to 334 °C for the PDD homopolymer. The phase behavior was found to depend on the feed composition. A comparison of a fully fluorinated commercially available product with a sample synthesized in carbon dioxide (without post-fluorination procedures) to match the composition and the molecular weight of the commercial sample showed no significant difference using IR spectroscopy, NMR spectroscopy, and differential scanning calorimetry, indicating similar microstructures. A simple method to determine the copolymer composition based on infrared spectroscopy was devel...}, number={19}, journal={MACROMOLECULES}, author={Michel, U and Resnick, P and Kipp, B and DeSimone, JM}, year={2003}, month={Sep}, pages={7107–7113} } @article{novick_desimone_carbonell_2004, title={Deposition of Thin Polymeric Films from Liquid Carbon Dioxide Using a High-Pressure Free-Meniscus Coating Process}, volume={43}, ISSN={0888-5885 1520-5045}, url={http://dx.doi.org/10.1021/ie030688z}, DOI={10.1021/ie030688z}, abstractNote={Free-meniscus coating processes can be used to deposit a wide variety of coatings. However, the physical properties of the coating solutions often lead to the deposition of nonuniform films. Recently, it has been recognized that compressed carbon dioxide can be used as an environmentally benign solvent for industrial processes. We investigate the use of liquid carbon dioxide as the solvent in free-meniscus coating processes because its physical properties are much different from standard coating solvents. The surface tension and viscosity of liquid carbon dioxide are an order of magnitude smaller than those of typical solvents. Additionally, the density of liquid carbon dioxide is strongly dependent on temperature and pressure. The Tallmadge four-force inertial theory is used to demonstrate that these unique physical properties will result in the formation of thinner films at the same withdrawal velocities as those used with conventional solvents. We then demonstrate experimentally that process variables ...}, number={2}, journal={Industrial & Engineering Chemistry Research}, publisher={American Chemical Society (ACS)}, author={Novick, Brian J. and DeSimone, Joseph M. and Carbonell, Ruben G.}, year={2004}, month={Jan}, pages={515–524} } @article{bessel_denison_desimone_deyoung_gross_schauer_visintin_2003, title={Etchant solutions for the removal of Cu(0) in a supercritical CO2-based "dry" chemical mechanical planarization process for device fabrication}, volume={125}, ISSN={["1520-5126"]}, DOI={10.1021/ja034091m}, abstractNote={The microelectronics industry is focused on increasing chip complexity, improving the density of electron carriers, and decreasing the dimensions of the interconnects into the sub-0.25 mum regime while maintaining high aspect ratios. Water-based chemical mechanical planarization or polishing (CMP) faces several technical and environmental challenges. Condensed CO2 has significant potential for replacing current CMP solvents as a "dry" etching medium because of its unique properties. In working toward a condensed CO2-based CMP process, we have successfully investigated the oxidation and chelation of solid copper metal in liquid and supercritical CO2 using ethyl peroxydicarbonate and a beta-diketone chelating agent.}, number={17}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Bessel, CA and Denison, GM and DeSimone, JM and DeYoung, J and Gross, S and Schauer, CK and Visintin, PM}, year={2003}, month={Apr}, pages={4980–4981} } @book{desimone_tumas_2003, place={New York}, title={Green Chemistry Using Liquid and Supercritical Carbon Dioxide}, ISBN={0195154835}, publisher={Oxford University Press}, year={2003} } @article{jones_yang_irene_gross_wagner_deyoung_desimone_2003, title={HF etchant solutions in supercritical carbon dioxide for "Dry" etch processing of microelectronic devices}, volume={15}, ISSN={["1520-5002"]}, DOI={10.1021/cm034235w}, abstractNote={A “dry” supercritical CO2-based etchant solution containing HF/pyridine as an anhydrous HF source effectively dissolves SiO2 thin films on silicon wafers. These dilute etchant solutions are active in removal of post-etch residues in back-end-of-line cleaning of microelectronic structures.}, number={15}, journal={CHEMISTRY OF MATERIALS}, author={Jones, CA and Yang, DX and Irene, EA and Gross, SM and Wagner, M and DeYoung, J and DeSimone, JM}, year={2003}, month={Jul}, pages={2867–2869} } @article{monge_mas_hamzaoui_kassis_desimone_schué_2003, title={Improvement of silicone endothelialization by treatment with allylamine and/or acrylic acid low-pressure plasma}, volume={87}, ISSN={0021-8995}, url={http://dx.doi.org/10.1002/app.11608}, DOI={10.1002/app.11608}, abstractNote={AbstractPlasma polymerization of allylamine, acrylic acid, and an allylamine/acrylic acid mixture on Silastic® silicone rubber led to a strong increase in the silicone rubber's hydrophilicity and surface energy. Analysis of the deposited layer by X‐ray photoelectron spectroscopy with 20° and 70° takeoff angles showed segregation of the atoms according to the depth and the incorporation of amino groups, oxygenated groups, and both. The endothelialization of untreated and treated samples was evaluated by the seeding and growth of aorta epithelial cells from pigs in cellular adherence (%), doubling time (in hours), and confluent density (104 cells/cm2). The best results were obtained with the allylamine/acrylic acid mixture treatment, which brought a biocompatibility to Silastic® similar to classic tissue culture on polystyrene plates. The interpretation was based on the presence of NH/CO2− microareas in the deposited layer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1794–1802, 2003}, number={11}, journal={Journal of Applied Polymer Science}, publisher={Wiley}, author={Monge, Sophie and Mas, André and Hamzaoui, Amina and Kassis, Camille M. and Desimone, Joseph M. and Schué, François}, year={2003}, month={Jan}, pages={1794–1802} } @article{lee_harper_desimone_murray_2003, title={Ion Atmosphere Relaxation Control of Electron Transfer Dynamics in a Plasticized Carbon Dioxide Redox Polyether Melt}, volume={125}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja0287128}, DOI={10.1021/ja0287128}, abstractNote={The sorption of CO(2) into the highly viscous, semisolid hybrid redox polyether melt, [Co(phenanthroline)(3)](MePEG-SO(3))(2), where MePEG-SO(3) is a MW 350 polyether-tailed sulfonate anion, remarkably accelerates charge transport in this molten salt material. Electrochemical measurements show that as CO(2) pressure is increased from 0 to 800 psi (54 atm) at 23 degrees C, the physical diffusion coefficient D(PHYS) of the Co(II) species, the rate constant k(EX) for Co(II/I) electron self-exchange, and the physical diffusion coefficient of the counterion D(COUNTERION) all increase, from 4.3 x 10(-10) to 6.4 x 10(-9) cm(2)/s, 4.1 x 10(6) to 1.6 x 10(7) M(-1) s(-1), and 3.3 x 10(-9) to 1.6 x 10(-8) cm(2)/s, respectively. Plots of log(k(EX)) versus log(D(PHYS)) and of log(k(EX)) versus log(D(COUNTERION)) are linear, showing that electron self-exchange rate constants are closely associated with processes that also govern D(PHYS) and D(COUNTERION). Slopes of the plots are 0.68 and 0.98, respectively, indicating a better linear correlation between k(EX) and D(COUNTERION). The evidence indicates that k(EX) can be controlled by relaxation of the counterion atmosphere about the Co complexes in the semisolid redox polyether melts. Because the counterion relaxation is in turn controlled by polyether "solvent" fluctuations, this is a new form of solvent dynamics control of electron transfer.}, number={4}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Lee, Dongil and Harper, Amanda S. and DeSimone, Joseph M. and Murray, Royce W.}, year={2003}, month={Jan}, pages={1096–1103} } @misc{carbonell_desimone_novick_2003, title={Method for meniscuscoating a substrate with a polymeric precurso}, volume={6,652,920}, number={2003 Nov. 25}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M. and Novick, B. J.}, year={2003}, month={Nov} } @article{nagashima_lee_xu_johnston_desimone_johnson_2003, title={NMR studies of water transport and proton exchange in water-in-carbon dioxide microemulsions}, volume={107}, ISSN={["1520-6106"]}, DOI={10.1021/jp0222705}, abstractNote={Water-in-carbon dioxide (W/C) microemulsions stabilized by an ammonium carboxylate perfluoropolyether (PFPECOO-NH4+) surfactant are studied with NMR diffusion and relaxation methods with the aim of obtaining information on the dynamics of this system, as well as aiding in the design of new surfactants that can form stable microemulsions in CO2. Short proton transverse relaxation times (3−10 ms) measured for water and ammonium ions are shown to agree with a simple proton exchange model. As the pressure is lowered below the phase boundary, the NMR spectra indicate that surfactant migrates to the new liquid phase along with the water. Diffusion coefficients are reported in the CO2 density range of 0.88−1.00 g/mL at 25 °C. The fractional amounts of water diffusion in bulk CO2, within the droplets, and through the water channels are delineated quantitatively. In decreasing the density from 0.96 to 0.88 g/mL, the water diffusion coefficient increases by a factor of 2 while the diffusion coefficients for ammoniu...}, number={9}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Nagashima, K and Lee, CT and Xu, B and Johnston, KP and DeSimone, JM and Johnson, CS}, year={2003}, month={Mar}, pages={1962–1968} } @misc{desimone_carson_shiho_lizotte_2003, title={Polymerization of non-fluorinated monomers in carbon dioxide}, volume={6,512,062}, number={2003 Jan. 28}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carson, T. J. and Shiho, H. and Lizotte, J.}, year={2003}, month={Jan} } @inbook{folk_desimone_2003, title={Polysiloxanes in compressed carbon dioxide}, volume={838}, ISBN={0841238049}, DOI={10.1021/bk-2003-0838.ch008}, abstractNote={Compressed carbon dioxide (CO2) is an environmentally friendly solvent alternative with potential for extensive use in industrial processes. Polysiloxanes are one of only a few classes of polymers that are soluble in this medium. This chapter reviews the properties and synthesis of polysiloxanes in liquid and supercritical CO2, as well as their areas of utilization.}, booktitle={Synthesis and properties of silicones and silicone-modified materials}, publisher={Washington, DC: American Chemical Society}, author={Folk, S. L. and Desimone, J. A.}, year={2003}, pages={79–93} } @article{lee_donkers_desimone_murray_2003, title={Voltammetry and Electron-Transfer Dynamics in a Molecular Melt of a 1.2 nm Metal Quantum Dot}, volume={125}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja029030n}, DOI={10.1021/ja029030n}, abstractNote={New molecular melts of nanoparticles have been obtained by place exchanging thiolated poly(ethyleneglycol, MW = 350) ligands into the monolayer shells of the quantum dot nanoparticle Au38(phenylethylthiolate)24. These melts are nearly monodisperse in monolayer protected Au clusters with core diameters of approximately 1.2 nm. LiClO4 electrolyte can be dissolved in the melt via the PEG component of the protecting monolayer, producing an ionically conductive nanophase and enabling voltammetry of the undiluted, semisolid nanoparticle molecular melt. The optical and electrochemical charging properties of the small nanoparticles have molecule-like characteristics (as opposed to quantized double layer charging) both in dilute fluid-solvent solutions and as undiluted melts. Potential step chronoamperometry shows that electronic charge is transported through the melt by diffusion-like core-core electron hopping reactions with a rate constant of 2 x 104 s-1.}, number={5}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Lee, Dongil and Donkers, Robert L. and DeSimone, Joseph M. and Murray, Royce W.}, year={2003}, month={Feb}, pages={1182–1183} } @article{kennedy_desimone_roberts_2002, title={A commentary on "Carbon dioxide-poly(vinylidene fluoride) interactions at high pressure"}, volume={40}, ISSN={["0887-6266"]}, DOI={10.1002/polb.10103}, abstractNote={Journal of Polymer Science Part B: Polymer PhysicsVolume 40, Issue 6 p. 602-604 Rapid Communication A commentary on “Carbon Dioxide–Poly(vinylidene Fluoride) Interactions at High Pressure” Karen A. Kennedy, Karen A. Kennedy Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Search for more papers by this authorJoseph M. Desimone, Joseph M. Desimone Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905 Department of Chemistry, CB 3290, Venable and Kenan Laboratories, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290Search for more papers by this authorGeorge W. Roberts, Corresponding Author George W. Roberts groberts@eos.ncsu.edu Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Search for more papers by this author Karen A. Kennedy, Karen A. Kennedy Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Search for more papers by this authorJoseph M. Desimone, Joseph M. Desimone Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905 Department of Chemistry, CB 3290, Venable and Kenan Laboratories, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290Search for more papers by this authorGeorge W. Roberts, Corresponding Author George W. Roberts groberts@eos.ncsu.edu Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905Search for more papers by this author First published: 01 February 2002 https://doi.org/10.1002/polb.10103Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume40, Issue615 March 2002Pages 602-604 RelatedInformation}, number={6}, journal={JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS}, author={Kennedy, KA and Desimone, JM and Roberts, GW}, year={2002}, month={Mar}, pages={602–604} } @article{saraf_gerard_wojcinski_charpentier_desimone_roberts_2002, title={Continuous precipitation polymerization of vinylidene fluoride in supercritical carbon dioxide: Formation of polymers with bimodal molecular weight distributions}, volume={35}, ISSN={["1520-5835"]}, DOI={10.1021/ma0203602}, abstractNote={The polymerization of vinylidene fluoride in supercritical carbon dioxide was studied in a continuous stirred tank reactor using diethylperoxydicarbonate as the free radical initiator. Experiments were carried out to investigate the effect of inlet monomer concentration, temperature, average residence time, and agitation on the polymerization rate, the average molecular weights, and the molecular weight distribution of the poly(vinylidene fluoride). A homogeneous kinetic model that includes inhibition due to chain transfer to monomer predicted the polymerization rates reasonably well. However, imperfect mixing, rather than a chemical effect, may have caused the apparent inhibition observed at high monomer concentrations. At inlet monomer concentrations greater than about 1.5 M, broad and bimodal molecular weight distributions were observed. An extended homogeneous kinetic model that includes chain transfer to polymer predicted the polydispersities reasonably well. This model also predicted a region of ino...}, number={21}, journal={MACROMOLECULES}, author={Saraf, MK and Gerard, S and Wojcinski, LM and Charpentier, PA and DeSimone, JM and Roberts, GW}, year={2002}, month={Oct}, pages={7976–7985} } @article{saraf_wojcinski_kennedy_gerard_charpentier_desimone_roberts_2002, title={Continuous precipitation polymerization of vinylidene fluoride in supercritical carbon dioxide: Molecular weight distribution}, volume={182}, ISSN={["1521-3900"]}, DOI={10.1002/1521-3900(200206)182:1<119::AID-MASY119>3.0.CO;2-P}, abstractNote={The surfactant-free precipitation polymerization of vinylidene fluoride (VF2) in supercritical carbon dioxide was studied in a continuous stirred autoclave. The polymerization temperature ranged from 65 to 85°C, the average residence time in the reactor varied from 10 to 50 min., and the pressure was between 210 and 305 bar. Diethyl peroxydicarbonate was used as the initiator. The fractional conversion of monomer varied from 7 to 26%, the number-average molecular weight of the polymer was between about 14,000 and 79,000, and the weight-average molecular weight was between about 21,000 and 700,000. In many cases, the polymer exhibited a bimodal molecular-weight distribution, especially at high monomer concentrations.}, journal={MACROMOLECULAR SYMPOSIA}, author={Saraf, MK and Wojcinski, LM and Kennedy, KA and Gerard, S and Charpentier, PA and DeSimone, J and Roberts, GW}, year={2002}, month={Jun}, pages={119–129} } @article{flowers_hoggan_desimone_carbonell_2002, title={Designing Photoresist Systems for Microlithography in Carbon Dioxide}, volume={705}, journal={Materials Research Society Symposium Proceedings}, author={Flowers, D. and Hoggan, E. and DeSimone, J.M. and Carbonell, R.}, year={2002}, pages={81–87} } @article{xu_nagashima_desimone_johnson_2003, title={Diffusion of water in liquid and supercritical carbon dioxide: An NMR study}, volume={107}, ISSN={["1089-5639"]}, DOI={10.1021/jp021943g}, abstractNote={Tracer diffusion coefficients have been measured for water in liquid and supercritical carbon dioxide (CO2) from 10 to 35 °C in the pressure range from 130 to 300 bar. The measurements were performed by means of pulsed field gradient NMR (PFG-NMR) methods incorporating compensation for electrical eddy currents and mass convection. In the NMR active volume, the sample was contained in a 1.4 mm i.d. PEEK tube with provisions for recirculation and external sample loading. The diffusion coefficients are consistent with the Stokes−Einstein equation with “slip” boundary conditions and a hydrodynamic radius of 1.7 A for water in the high temperature and low density region. In the low temperature and high density region, the diffusion coefficients indicate either a trend toward “stick” boundary conditions or the dynamic clustering of water molecules.}, number={1}, journal={JOURNAL OF PHYSICAL CHEMISTRY A}, author={Xu, B and Nagashima, K and DeSimone, JM and Johnson, CS}, year={2003}, month={Jan}, pages={1–3} } @article{henon_carbonell_desimone_2002, title={Effect of polymer coatings from CO2 on water-vapor transport in porous media}, volume={48}, ISSN={["1547-5905"]}, DOI={10.1002/aic.690480504}, abstractNote={AbstractA variety of perfluorinated polyethers were coated onto surfaces of marble, sandstone and limestone samples from solutions in supercritical carbon dioxide. These polymers make ideal protectants for civil infrastructure by making stone surfaces hydrophobic and preventing penetration and deterioration of the stone by acid rain. The effective diffusivities of water vapor through coated and uncoated stones were measured as a function of polymer applied per unit area of sample. An analysis of the diffusive transport of water through the stones led to estimates of the penetration depths of the polymers and the percentages of blockage of the pores in the coated layers as a function of polymer surface coverage. Penetration depths were seen to strongly depend on the mean size and porosity of the stones. It is important for water‐vapor diffusion to occur through the samples to prevent water condensation inside polymer‐coated structural materials.}, number={5}, journal={AICHE JOURNAL}, author={Henon, FE and Carbonell, RG and DeSimone, JM}, year={2002}, month={May}, pages={941–952} } @article{lee_hutchison_leone_desimone_murray_2002, title={Electron and Mass Transport in Hybrid Redox Polyether Melts Contacted with Carbon Dioxide}, volume={124}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja026209p}, DOI={10.1021/ja026209p}, abstractNote={Films of neat metal salts with covalently attached oligoether side chains ([Co(bpy(CO(2)MePEG-350)(2))(3)](ClO(4))(2); bpy is 2,2'-bipyridine, and MePEG-350 is methyl-terminated oligomeric ethylene oxide with an average molecular weight of 350 Da) undergo marked changes in physical and electrochemical properties upon contact with CO(2). Electrochemical measurements indicate that the physical diffusion coefficient (D(PHYS)) of the Co(II) species, the observed rate constant for Co(II/I) self-exchange (k(EX)), and the physical diffusion coefficient of the perchlorate counterion (D(ClO4)) increase from 2.4 x 10(-11) to 7.0 x 10(-10) cm(2)/s, 6.8 x 10(5) to 4.5 x 10(6) M(-1) s(-1), and 3.4 x 10(-10) to 4.3 x 10(-9) cm(2)/s, respectively, as CO(2) pressure is increased from 0 to 2000 psi at 23 degrees C. A reduction in activation energy accompanies the enhancement of each of these properties over this pressure range. Increasing CO(2) pressure from ambient to 1000 psi causes the films to swell 13%, and free-volume theory explains the enhanced mass transport properties of the films. The origin of increases in electron-transfer kinetics is considered. Plots of log(k(EX)) versus log(D(PHYS)) and log(k(EX)) versus log(D(ClO4)) are both linear. This suggests that electron self-exchange is controlled by factors that also affect log(D(PHYS)) or log(D(ClO4)). One explanation is based on plasticization of the oligoether side-chain motions by CO(2) that affect ether dipole repolarization and Co complex diffusion rates. A second explanation for the changes in k(EX) is based on control of electron transfer by relaxation of counterions neighbor to the Co complexes, which is measured by D(ClO4). Both explanations represent a kind of solvent dynamics control of k(EX).}, number={31}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Lee, Dongil and Hutchison, John C. and Leone, Anthony M. and DeSimone, Joseph M. and Murray, Royce W.}, year={2002}, month={Aug}, pages={9310–9317} } @article{deitzel_kosik_mcknight_beck tan_desimone_crette_2002, title={Electrospinning of polymer nanofibers with specific surface chemistry}, volume={43}, ISSN={0032-3861}, url={http://dx.doi.org/10.1016/s0032-3861(01)00594-8}, DOI={10.1016/s0032-3861(01)00594-8}, abstractNote={Electrospinning is a process by which sub-micron polymer fibers can be produced using an electrostatically driven jet of polymer solution (or polymer melt). Electrospun textiles are of interest in a wide variety of applications including semi-permeable membranes, filters, composite applications, and as scaffolding for tissue engineering. The goal of the research presented here is to demonstrate that it is possible to produce sub-micron fibers with a specific surface chemistry through electrospinning. This has been accomplished by electrospinning a series of random copolymers of PMMA-r-TAN from a mixed solvent of toluene and dimethyl formamide. X-ray Photoelectron Spectroscopy (XPS) analysis shows that the atomic percentage of fluorine in the near surface region of the electrospun fibers is about double the atomic percentage of fluorine found in a bulk sample of the random copolymer, as determined by elemental analysis. These results are in good agreement with XPS and water contact angle results obtained from thin films of the same copolymer materials.}, number={3}, journal={Polymer}, publisher={Elsevier BV}, author={Deitzel, J.M. and Kosik, W. and McKnight, S.H. and Beck Tan, N.C. and DeSimone, J.M. and Crette, S.}, year={2002}, month={Feb}, pages={1025–1029} } @article{efimenko_novick_carbonell_desimone_genzer_2002, title={Formation of self-assembled monolayers of semifluorinated and hydrocarbon chlorosilane precursors on silica surfaces from liquid carbon dioxide}, volume={18}, ISSN={["0743-7463"]}, DOI={10.1021/la011813j}, abstractNote={We report on the formation and properties of self-assembled monolayers (SAMs) prepared by depositing semifluorinated and hydrocarbon trichlorosilane precursors, F(CF2)8(CH2)2SiCl3 (F8H2) and H(CH2)18SiCl3 (H18), respectively, from vapor, organic solvent, and liquid CO2 (l-CO2). Contact angle measurements of the SAM deposition kinetics reveal that regardless of the molecule type, the deposition rates from l-CO2 exceed those from vapor or organic solvents by several orders of magnitude. We derive two different transport models describing the formation of SAMs. We show that while the diffusion-limited model is not capable of describing the experimental data, the adsorption-limited model captures the major features of the adsorption kinetics quite well. We apply the results of the adsorption-limited model to conclude that the observed behavior is a consequence of (i) a relatively high bulk concentration (l-CO2 vs vapor) and (ii) higher solution diffusivity (l-CO2 vs organic solvent) of the silanes in l-CO2. N...}, number={16}, journal={LANGMUIR}, author={Efimenko, K and Novick, B and Carbonell, RG and DeSimone, JM and Genzer, J}, year={2002}, month={Aug}, pages={6170–6179} } @article{siripurapu_gay_royer_desimone_spontak_khan_2002, title={Generation of microcellular foams of PVDF and its blends using supercritical carbon dioxide in a continuous process}, volume={43}, ISSN={["1873-2291"]}, DOI={10.1016/S0032-3861(02)00407-X}, abstractNote={Use of supercritical carbon dioxide (scCO2) as a blowing agent to generate microcellular polymer foams (MPFs) has recently received considerable attention due to environmental concerns associated with conventional organic blowing agents. While such foams derived from amorphous thermoplastics have been previously realized, semicrystalline MPFs have not yet been produced in a continuous scCO2 process. This work describes the foaming of highly crystalline poly(vinylidene fluoride) (PVDF) and its blends with amorphous polymers during extrusion. Foams composed of neat PVDF and immiscible blends of PVDF with polystyrene exhibit poor cell characteristics, whereas miscible blends of PVDF with poly(methyl methacrylate) (PMMA) yield foams possessing vastly improved morphologies. The results reported herein illustrate the effects of blend composition and scCO2 solubility on PVDF/PMMA melt viscosity, which decreases markedly with increasing PMMA content and scCO2 concentration. Morphological characterization of microcellular PVDF/PMMA foams reveals that the cell density increases as the PMMA fraction is increased and the foaming temperature is decreased. This study confirms that novel MPFs derived continuously from semicrystalline polymers in the presence of scCO2 can be achieved through judicious polymer blending.}, number={20}, journal={POLYMER}, author={Siripurapu, S and Gay, YJ and Royer, JR and DeSimone, JM and Spontak, RJ and Khan, SA}, year={2002}, month={Sep}, pages={5511–5520} } @article{lo celso_triolo_triolo_mcclain_desimone_heenan_amenitsch_triolo_2002, title={Industrial applications of the aggregation of block copolymers in supercritical CO 2 : a SANS study}, volume={74}, ISSN={0947-8396 1432-0630}, url={http://dx.doi.org/10.1007/s003390101240}, DOI={10.1007/s003390101240}, number={0}, journal={Applied Physics A: Materials Science & Processing}, publisher={Springer Science and Business Media LLC}, author={Lo Celso, F. and Triolo, A. and Triolo, F. and McClain, J. and Desimone, J.M. and Heenan, R.K. and Amenitsch, H. and Triolo, R.}, year={2002}, month={Dec}, pages={s1427–s1429} } @article{triolo_lo celso_triolo_amenitsch_steinhart_thiyagarajan_wells_desimone_triolo_2002, title={Kinetics of block-copolymer aggregation in super critical CO2}, volume={307-310}, ISSN={0022-3093}, url={http://dx.doi.org/10.1016/s0022-3093(02)01553-3}, DOI={10.1016/s0022-3093(02)01553-3}, abstractNote={Small angle X-ray and neutron scattering (SAXS and SANS) are used to obtain structural information on the aggregation behavior of block-copolymers dissolved in supercritical CO2. The SANS technique is used to provide a detailed structural model for the micellar aggregates, which form below the critical micellization density (CMD), that we defined in our previous work. The SAXS technique (with a synchrotron source) is used to provide the first experimental information concerning the kinetic features of both formation and decomposition of such aggregates as soon as pressure jumps are applied to the solutions across the CMD. 2002 Elsevier Science B.V. All rights reserved.}, journal={Journal of Non-Crystalline Solids}, publisher={Elsevier BV}, author={Triolo, A. and Lo Celso, F. and Triolo, F. and Amenitsch, H. and Steinhart, M. and Thiyagarajan, P. and Wells, S. and DeSimone, J.M. and Triolo, R.}, year={2002}, month={Sep}, pages={725–730} } @misc{desimone_khan_royer_spontak_walker_2002, title={Method of making foamed materialsUSing surfactants and carbon dioxide}, volume={6,403,663}, number={2002 Jun. 11}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Khan, S. A. and Royer, J. R. and Spontak, R. J. and Walker, T. A.}, year={2002} } @article{arnold_nagai_spontak_freeman_leroux_betts_desimone_digiano_stebbins_linton_et al._2002, title={Microphase-Separated Block Copolymers Comprising Low Surface Energy Fluorinated Blocks and Hydrophilic Blocks:  Synthesis and Characterization}, volume={35}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma0119631}, DOI={10.1021/ma0119631}, abstractNote={The synthesis and characterization of diblock and triblock copolymers produced by a two-component iniferter system is reported. These materials, designed for possible water treatment applications, consist of a hydrophilic poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) block and a very low surface energy poly(1,1‘-dihydroperfluorooctyl methacrylate) (PFOMA) or poly(1,1,2,2-tetrahydroperfluorooctyl acrylate) (PTAN) block. Angle-dependent X-ray spectroscopy results and water contact angle measurements indicate that the surfaces of PDMAEMA-b-PFOMA diblock copolymers consist primarily of PFOMA. Transmission electron microscopy reveals that the block copolymers are microphase-separated, exhibiting either cylindrical or layered morphologies that do not change appreciably upon exposure to water. Both water uptake and water flux increase with increasing PDMAEMA content.}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Arnold, M. E. and Nagai, K. and Spontak, Richard and Freeman, B. D. and Leroux, D. and Betts, D. E. and Desimone, J. M. and Digiano, F. A. and Stebbins, C. K. and Linton, R. W. and et al.}, year={2002}, month={Apr}, pages={3697–3707} } @article{keiper_simhan_desimone_wignall_melnichenko_frielinghaus_2002, title={New phosphate fluorosurfactants for carbon dioxide}, volume={124}, ISSN={["1520-5126"]}, DOI={10.1021/ja0122142}, abstractNote={Anionic phosphate fluorosurfactants were shown to self-assemble into water-in-carbon dioxide microemulsions. The surfactants, having either two fluorinated chains or one fluorinated chain and one hydrocarbon chain, facilitated significant water uptake in CO2. Small angle neutron scattering (SANS) measurements of surfactant/water/CO2 solutions confirmed the presence of nanometer-scale aggregates, indicative of microemulsion formation.}, number={9}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Keiper, JS and Simhan, R and DeSimone, JM and Wignall, GD and Melnichenko, YB and Frielinghaus, H}, year={2002}, month={Mar}, pages={1834–1835} } @article{hoggan_novick_desimone_carbonell_2002, title={Novel Electronic Coatings Using Liquid CO2}, volume={16}, journal={Semiconductor Fabtech}, author={Hoggan, E.N. and Novick, B.J. and DeSimone, J.M. and Carbonell, R.G.}, year={2002}, pages={169–173} } @article{royer_gay_adam_desimone_khan_2002, title={Polymer melt rheology with high-pressure CO2 using a novel magnetically levitated sphere rheometer}, volume={43}, ISSN={["0032-3861"]}, DOI={10.1016/S0032-3861(01)00804-7}, abstractNote={A magnetically levitated sphere rheometer (MLSR) designed to measure viscosity of fluids exposed to high-pressure carbon dioxide has been developed. This device consists of a magnetic sphere submerged inside a test fluid within a high-pressure housing and levitated at a fixed point. The housing is constructed from an optically transparent sapphire tube. The cylindrical tube can be moved vertically to generate a shear flow around the levitated sphere. The difference in magnetic force required to levitate the sphere at rest and under fluid motion can be directly related to fluid viscosity. Rheological properties, specifically zero shear viscosities, of transparent high-pressure materials can be measured to a precision of about 5% and over a wide range of viscosities. In addition, operation at constant pressure, in concentration regimes from a pure polymer to an equilibrated polymer/supercritical fluid solution, and at shear rates over several orders of magnitude is possible, eliminating many of the disadvantages associated with other high-pressure rheometers. Experiments performed at different temperatures with a poly(dimethylsiloxane) melt at atmospheric pressure are compared with data from a commercial Couette rheometer to demonstrate device sensitivity and viability. Measurements of a PDMS melt plasticized by high-pressure CO2 are performed to illustrate the utility of the new rheometer under high-pressure conditions. Experimental data are obtained at 30 °C, for pressures up to 20.7 MPa and CO2 concentrations reaching 30 wt%. Viscosity reductions of nearly two orders of magnitude compared with the pure polymer viscosity at atmospheric pressure are observed. Additionally, the effects of pressure on a polymer/CO2 system are directly investigated taking advantage of the constant pressure operation mode of the MLSR. This allows us, for the first time in experiments of polymers with supercritical fluids, to decouple the effects of CO2 concentration and pressure in a single device.}, number={8}, journal={POLYMER}, author={Royer, JR and Gay, YJ and Adam, M and DeSimone, JM and Khan, SA}, year={2002}, month={Apr}, pages={2375–2383} } @article{taylor_keiper_desimone_2002, title={Polymer self-assembly in carbon dioxide}, volume={41}, ISSN={["0888-5885"]}, DOI={10.1021/ie010715q}, abstractNote={The foreseeable future should find carbon dioxide used in an ever-increasing number of industrial applications, from materials production to lithography. Many such processes will involve the use of amphiphilic compounds, which have greatly enhanced the versatility and potential of CO2 as a solvent. In a relatively short period of time, research on the self-assembly of amphiphilic polymers in CO2 has undergone remarkable maturation. The growth is largely due to strong fundamental and practical interest, as well as a cache of techniques available to characterize the self-assembly process. This article serves to summarize what has thus far been discovered about polymer self-assembly in CO2, what needs further examination, and where the field is headed.}, number={18}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Taylor, DK and Keiper, JS and DeSimone, JM}, year={2002}, month={Sep}, pages={4451–4459} } @article{mcallister_sazani_adam_cho_rubinstein_samulski_desimone_2002, title={Polymeric nanogels produced via inverse microemulsion polymerization as potential gene and antisense delivery agents}, volume={124}, ISSN={["1520-5126"]}, DOI={10.1021/ja027759q}, abstractNote={Polymeric nanogel vectors were developed for cellular gene and antisense delivery. Inverse microemulsion polymerization was utilized to synthesize biocompatible nanogels with controlled size, morphology, and composition. The chemical composition, size, polydispersity, stability, and swelling behavior of the nanogels were investigated by NMR, light scattering, transmission electron microscopy, and atomic force microscopy. The cell viability, uptake, and physical stability of nanogel-DNA complexes were evaluated under physiological conditions. Monodisperse nonionic and cationic nanogels were produced with controllable sizes ranging from 40 to 200 nm in diameter. The nanogels demonstrated extended stability in aqueous media and exhibited low toxicity in cell culture. Cationic nanogels formed monodisperse complexes with oligonucleotides and showed enhanced oligonucleotide uptake in cell culture. The nanogels synthesized in this study demonstrate potential utility as carriers of oligonucleotides and DNA for antisense and gene delivery.}, number={51}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={McAllister, K and Sazani, P and Adam, M and Cho, MJ and Rubinstein, M and Samulski, RJ and DeSimone, JM}, year={2002}, month={Dec}, pages={15198–15207} } @article{desimone_2002, title={Practical approaches to green solvents}, volume={297}, ISSN={["0036-8075"]}, DOI={10.1126/science.1069622}, abstractNote={Solvents are widely used in commercial manufacturing and service industries. Despite abundant precaution, they inevitably contaminate our air, land, and water because they are difficult to contain and recycle. Researchers have therefore focused on reducing solvent use through the development of solvent-free processes and more efficient recycling protocols. However, these approaches have their limitations, necessitating a pollution prevention approach and the search for environmentally benign solvent alternatives. This report highlights opportunities for the practical implementation of such green solvents.}, number={5582}, journal={SCIENCE}, author={DeSimone, JM}, year={2002}, month={Aug}, pages={799–803} } @misc{carbonell_desimone_2002, title={Spin cleaning methods}, volume={6,500,273}, number={2002 Feb 06}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M.}, year={2002}, month={Feb} } @article{senapati_keiper_desimone_wignall_melnichenko_frielinghaus_berkowitz_2002, title={Structure of Phosphate Fluorosurfactant Based Reverse Micelles in Supercritical Carbon Dioxide}, volume={18}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la025952s}, DOI={10.1021/la025952s}, abstractNote={The existence of microemulsions in the system composed of phosphate-based fluorosurfactant, water, and supercritical CO2 is demonstrated by small-angle neutron scattering experiments. A computer simulation study performed on a reverse micelle created in this system shows that the micelle remains stable over a 4 ns time period of the simulation. While the data obtained from the experiments provide information about the size of the reverse micelle, the data obtained from the simulations provide additional information about the shape and structure of such a micelle.}, number={20}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Senapati, Sanjib and Keiper, Jason S. and DeSimone, Joseph M. and Wignall, George D. and Melnichenko, Yuri B. and Frielinghaus, Henrich and Berkowitz, Max L.}, year={2002}, month={Oct}, pages={7371–7376} } @misc{desimone_carbonell_2001, title={Apparatus for liquid carbon dioxide systems}, volume={6,383,289}, number={2002 May 7}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carbonell, R. G.}, year={2001}, month={Feb} } @article{ledford_shultz_gates_white_desimone_brookhart_2001, title={Bond Angle Effects on the Migratory Insertion of Ethylene and Carbon Monoxide into Palladium(II)−Methyl Bonds in Complexes Bearing Bidentate Phosphine Ligands}, volume={20}, ISSN={0276-7333 1520-6041}, url={http://dx.doi.org/10.1021/om010489k}, DOI={10.1021/om010489k}, abstractNote={Labile (P−P)Pd(CH3)(OEt2)+BAr‘4- complexes (2) have been prepared via protonation of (P−P)PdMe2 (1), where P−P = cis-1,2-bis(diphenylphosphino)ethylene (a, dppee), 1,2-bis(diphenylphosphino)benzene (b, dpbz), 1,2-bis(diphenylphosphino)ethane (c, dppe), 1,2-bis(dimethylphosphino)ethane (d, dmpe), 1,3-bis(diphenylphosphino)propane (e, dppp), 1,3-bis(diisopropylphosphino)propane (f, dippp), 1,4-bis(diphenylphosphino)butane (g, dppb) and Ar‘ = 3,5-(CF3)2C6H3. Unstable complex 2d (P−P = dmpe) was generated in situ. X-ray structures are reported for 1e and 2e−g. Treatment of 2a−g with CO in CH2Cl2 at −90 °C yields the (P−P)Pd(CH3)(CO)+ complexes 3a−g. Barriers to migratory insertion in 3a−g were determined with the ordering to be:  3f (dippp) ≈ 3g (dppb) < 3e (dppp) ≪ 3a (dppee) ≈ 3b (dpbz) ≈ 3c (dppe) < 3d (dmpe). Exposure of 2a−g to ethylene at −80 °C yields the ethylene complexes (P−P)Pd(CH3)(C2H4)+ (5a−g). Barriers to migratory insertion in these complexes were determined by NMR spectroscopy to be:  5b (dpb...}, number={25}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Ledford, John and Shultz, C. Scott and Gates, Derek P. and White, Peter S. and DeSimone, Joseph M. and Brookhart, Maurice}, year={2001}, month={Dec}, pages={5266–5276} } @article{wells_desimone_2001, title={CO2 Technology Platform: An Important Tool for Environmental Problem Solving}, volume={40}, ISSN={1433-7851}, url={http://dx.doi.org/10.1002/1521-3773(20010202)40:3<518::aid-anie518>3.0.co;2-4}, DOI={10.1002/1521-3773(20010202)40:3<518::aid-anie518>3.0.co;2-4}, abstractNote={CO2 is a good solvent for many substances when compressed into its liquid or supercritical fluid state. Above the critical temperature and critical pressure (Tc =31 °C, Pc =73.8 bar, see Figure 1 for the phase diagram for CO2 ), CO2 has both gaslike viscosities and liquidlike densities. These moderate critical conditions allow CO2 to be used within safe commercial and laboratory operating conditions. Small changes in temperature and pressure cause dramatic changes in the density, viscosity, and dielectric properties of CO2 , making it a tunable solvent that can be tailored for various applications. Combined, these unique properties make CO2 a "solvent of choice" for the new millennium.}, number={3}, journal={Angewandte Chemie International Edition}, publisher={Wiley}, author={Wells, Sharon L. and DeSimone, Joseph}, year={2001}, month={Jan}, pages={518–527} } @inbook{jones, iii_desimone_2001, place={Hoboken}, edition={3rd}, title={Critical Phase Polymerizations}, booktitle={Encyclopedia of Polymer Science and Engineering}, publisher={Wiley-Interscience}, author={Jones, III, C.A. and DeSimone, J.M.}, editor={Mark, H.Editor}, year={2001}, pages={111–127} } @article{gross_bunyard_erford_roberts_kiserow_desimone_2002, title={Determination of the equilibrium constant for the reaction between bisphenol A and diphenyl carbonate}, volume={40}, ISSN={["1099-0518"]}, DOI={10.1002/pola.10098}, abstractNote={AbstractDespite the industrial significance of poly(bisphenol A carbonate), there is a scarcity of open literature on the equilibrium of the melt‐phase process. In fact, the equilibrium constant (Keq) for this reaction has never been measured directly. This article describes a process on the basis of NMR for the measurement of Keq for the reaction between bisphenol A and diphenyl carbonate in the presence and absence of a catalyst. The apparent enthalpy and entropy were calculated using a van't Hoff plot. Decomposition of bisphenol A is a common side reaction in the melt‐phase reaction performed at high temperatures in the presence of catalyst. The effect of these side reactions on the Keq in the presence of catalyst is determined. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 171–178, 2002}, number={1}, journal={JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY}, author={Gross, SM and Bunyard, WC and Erford, K and Roberts, GW and Kiserow, DJ and DeSimone, JM}, year={2002}, month={Jan}, pages={171–178} } @article{behles_desimone_2001, title={Developments in CO2 research}, volume={73}, ISSN={1365-3075 0033-4545}, url={http://dx.doi.org/10.1351/pac200173081281}, DOI={10.1351/pac200173081281}, abstractNote={Abstract CO2 can be a good solvent for many compounds when used in its compressed liquid or supercritical fluid state. Above its critical temperature and critical pressure (Tc = 31 C, Pc = 73.8 bar), CO2 has liquid-like densities and gas-like viscosities, which allows for safe commercial and laboratory operating conditions. Many small molecules are readily soluble in CO2, whereas most macromolecules are not. This has prompted development of several classes of small molecule and polymeric surfactants that enable emulsion and dispersion polymerizations as well as other technological processes.}, number={8}, journal={Pure and Applied Chemistry}, publisher={Walter de Gruyter GmbH}, author={Behles, Jacqueline A. and DeSimone, Joseph M.}, year={2001}, month={Aug}, pages={1281–1285} } @article{lee_hutchison_desimone_murray_2001, title={Diffusive Transport of Micelles and Monomeric Solutes in Supercritical CO2}, volume={123}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja0162818}, DOI={10.1021/ja0162818}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTDiffusive Transport of Micelles and Monomeric Solutes in Supercritical CO2Dongil Lee, John C. Hutchison, Joseph M. DeSimone, and Royce W. MurrayView Author Information Kenan Laboratories of Chemistry and NSF Center for Environmentally Responsible Solvents and Processes University of North Carolina Chapel Hill, North Carolina 27599 Cite this: J. Am. Chem. Soc. 2001, 123, 34, 8406–8407Publication Date (Web):August 2, 2001Publication History Received25 May 2001Revised9 July 2001Published online2 August 2001Published inissue 1 August 2001https://pubs.acs.org/doi/10.1021/ja0162818https://doi.org/10.1021/ja0162818rapid-communicationACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views290Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Diffusion,Emulsions,Micelles,Probes,Surfactants Get e-Alerts}, number={34}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Lee, Dongil and Hutchison, John C. and DeSimone, Joseph M. and Murray, Royce W.}, year={2001}, month={Aug}, pages={8406–8407} } @article{shiho_desimone_2001, title={Dispersion polymerization of glycidyl methacrylate in supercritical carbon dioxide}, volume={34}, ISSN={["0024-9297"]}, DOI={10.1021/ma0010074}, abstractNote={Herein we report a successful dispersion polymerization of glycidyl methacrylate (GMA) in carbon dioxide using a block copolymer consisting of polystyrene and poly(1,1-dihydroperfluorooctyl acrylate) (PFOA) as a stabilizer. Poly(GMA) was effectively emulsified in carbon dioxide using the amphiphilic diblock copolymer surfactant. Spherical particles were produced, although PFOA homopolymer was not particularly effective as a stabilizer. The initial concentrations of the monomer and stabilizer and the reaction pressure had substantial effects on the resulting size of the colloidal particles.}, number={5}, journal={MACROMOLECULES}, author={Shiho, H and DeSimone, JM}, year={2001}, month={Feb}, pages={1198–1203} } @misc{desimone_carbonell_crette_kendall_2001, title={Enzyme catalysis in carbon dioxide fluids}, volume={6,211,422}, number={2001 April 3}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carbonell, R. G. and Crette, S. A. and Kendall, J. L.}, year={2001}, month={Apr} } @article{chernyak_henon_harris_gould_franklin_edwards_desimone_carbonell_2001, title={Formation of perfluoropolyether coatings by the rapid expansion of supercritical solutions (RESS) process. Part 1: Experimental results}, volume={40}, ISSN={["0888-5885"]}, DOI={10.1021/ie010267m}, abstractNote={The rapid expansion of supercritical solutions (RESS) process is a promising environmentally benign technology for fine droplet or particle formation. The absence of organic solvents and narrow size distribution of RESS precipitates make this process attractive for polymer coating applications. In our work, this technique has been used to produce droplets of perfluoropolyethers from CO2 solutions without the aid of cosolvents for the coating of porous materials applied in monumental and civil infrastructures. The present work is aimed at gaining an understanding of the relationship between droplet and spray characteristics and RESS process conditions. As such, a combined experimental/computational approach is applied to a representative binary system consisting of a low-molecular-weight perfluoropolyether diamide (PFD) dissolved in supercritical CO2. Part 1 of this work presents phase equilibria measurements and polymer droplet size characterizations under different operating conditions. The effects of te...}, number={26}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Chernyak, Y and Henon, F and Harris, RB and Gould, RD and Franklin, RK and Edwards, JR and DeSimone, JM and Carbonell, RG}, year={2001}, month={Dec}, pages={6118–6126} } @article{shultz_desimone_brookhart_2001, title={Four- and Five-Coordinate CO Insertion Mechanisms in d8-Nickel(II) Complexes}, volume={123}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja0160896}, DOI={10.1021/ja0160896}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFour- and Five-Coordinate CO Insertion Mechanisms in d8-Nickel(II) ComplexesC. Scott Shultz, Joseph M. DeSimone, and Maurice BrookhartView Author Information Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill, North Carolina 27599-3290 Cite this: J. Am. Chem. Soc. 2001, 123, 37, 9172–9173Publication Date (Web):August 24, 2001Publication History Received26 April 2001Published online24 August 2001Published inissue 1 September 2001https://pubs.acs.org/doi/10.1021/ja0160896https://doi.org/10.1021/ja0160896rapid-communicationACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views1397Altmetric-Citations38LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Acyls,Alkyls,Carbonylation,Coordination compounds,Hydrocarbons Get e-Alerts}, number={37}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Shultz, C. Scott and DeSimone, Joseph M. and Brookhart, Maurice}, year={2001}, month={Sep}, pages={9172–9173} } @article{arnold_nagai_freeman_spontak_betts_desimone_pinnau_2001, title={Gas permeation properties of poly(1,1 '-dihydroperfluorooctyl acrylate), poly(1,1 '-dihydroperfluorooetyl methacrylate), and poly(styrene)-b-poly(1,1 '-dihydroperfluorooctyl acrylate) block copolymers}, volume={34}, ISSN={["0024-9297"]}, DOI={10.1021/ma010355i}, abstractNote={The permeabilities of rubbery poly(1,1‘-dihydroperfluorooctyl acrylate) (PFOA), glassy poly(1,1‘-dihydroperfluorooctyl methacrylate) (PFOMA), and poly(styrene)-b-poly(1,1‘-dihydroperfluorooctyl acr...}, number={16}, journal={MACROMOLECULES}, author={Arnold, ME and Nagai, K and Freeman, BD and Spontak, RJ and Betts, DE and DeSimone, JM and Pinnau, I}, year={2001}, month={Jul}, pages={5611–5619} } @article{royer_desimone_khan_2001, title={High-pressure rheology and viscoelastic scaling predictions of polymer melts containing liquid and supercritical carbon dioxide}, volume={39}, ISSN={0887-6266 1099-0488}, url={http://dx.doi.org/10.1002/polb.10057}, DOI={10.1002/polb.10057}, abstractNote={AbstractHigh‐pressure rheological behavior of polymer melts containing dissolved carbon dioxide (CO2) at concentrations up to 6 wt % were investigated using a high‐pressure extrusion slit die rheometer. In particular, the steady shear viscosity of poly(methyl methacrylate), polypropylene, low‐density polyethylene, and poly(vinylidene fluoride) with dissolved CO2 were measured for shear rates ranging from 1 to 500 s−1 and under pressure conditions up to 30 MPa. The viscosity of all samples revealed a reduction in the presence of CO2 with its extent dependent on CO2 concentration, pressure, and the polymer used. Two types of viscoelastic scaling models were developed to predict the effects of both CO2 concentration and pressure on the viscosity of the polymer melts. The first approach utilized a set of equations analogous to the Williams–Landel–Ferry equation for melts between the glass‐transition temperature (Tg) and Tg + 100 °C, whereas the second approach used equations of the Arrhenius form for melts more than 100 °C above Tg. The combination of these traditional viscoelastic scaling models with predictions for Tg depression by a diluent (Chow model) were used to estimate the observed effects of dissolved CO2 on polymer melt rheology. In this approach, the only parameters involved are physical properties of the pure polymer melt that are either available in the existing literature or can be measured under atmospheric conditions in the absence of CO2. The ability of the proposed scaling models to accurately predict the viscosity of polymer melts with dissolved high‐pressure CO2 were examined for each of the polymer systems. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 3055–3066, 2001}, number={23}, journal={Journal of Polymer Science Part B: Polymer Physics}, publisher={Wiley}, author={Royer, Joseph R. and DeSimone, Joseph M. and Khan, Saad A.}, year={2001}, pages={3055–3066} } @article{crette_desimone_2001, title={Latest Applications of Compressed Carbon Dioxide}, volume={49}, DOI={10.1002/nadc.20010490407}, abstractNote={AbstractIn der Nahrungsmittelindustrie seit einigen Jahrzehnten im Einsatz, rückt überkritisches oder fast überkritisches Kohlendioxid nun auch in der Polymersynthese, Textilreinigung, Oberflächenbeschichtung und Mikrolithographie in den Blickpunkt. Die Gründe für den Aufschwung neuer Kohlendioxidtechniken sind in Verfahrens‐ und ökologischen Vorteilen zu suchen.}, number={4}, journal={Nachrichten Aus der Chemie}, author={Crette, S.A. and DeSimone, J.M.}, year={2001}, pages={462–466} } @article{yoshida_wells_desimone_2001, title={Light scattering study of poly(tert-butyl methacrylate) -block-poly(1,1-dihydroperfluorooctyl methacrylate) in liquid and supercritical carbon dioxide - Towards the reversible control of self-assembly}, volume={58}, ISSN={["0386-2186"]}, DOI={10.1295/koron.58.507}, abstractNote={二酸化炭素に両親媒性のブロック腫合体であるポリメタクリル酸tert-ブチル-block-ポリ (メタクリル酸1, 1-ジヒドロパーフルオロオクチル) ジブロック共重合体 (P' BMA-block-PFOMA) の, 液体および超臨界二酸化炭素中でのミセル形成について光散乱解析を用いて検討を行った. 動的光散乱解析の結果, P' BMAセグメントの分子量が4000以上のプロック共重合体は, 超臨界二酸化炭素中で分子量分布の狭いミセルを形成することがわかった. 特に, 半径が13～21nmの範囲にあるミセルを形成するP' BMA-block-PFOMAは, CO2密度0.87～1.04g/cm3にミセルから単量体への転移をもつことが見いだされた. その転移は温度およびジブロック共重合体備成する両方のポリマー鎖長に依存した. 本研究は, CO2中におけるブロック共重合体のミセルから単量体への転移が, ジブロック共重合体のセグメント鎖長によって制御されることを初めて実証したものである. このことは, CO2の溶媒特性だけでなくジブロック共重合体のセグメント鎖長の選択によっても, 共重合体の自己組織化の制御が可能であることを示している.}, number={10}, journal={KOBUNSHI RONBUNSHU}, author={Yoshida, E and Wells, SL and DeSimone, JM}, year={2001}, pages={507–513} } @misc{desimone_carbonell_2001, title={Methods of spin cleaning substrates using carbon dioxide liquid}, volume={6,240,936}, number={2001 June 5}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carbonell, R. G.}, year={2001}, month={Jun} } @article{desimone_selva_tundo_2001, title={Nucleophilic Displacements in Supercritical Carbon Dioxide Using Silica-Supported Phase-Transfer Agents}, volume={66}, ISSN={0022-3263 1520-6904}, url={http://dx.doi.org/10.1021/jo001337m}, DOI={10.1021/jo001337m}, abstractNote={Carbon dioxide in both its liquid and supercritical states is receiving more and more interest for organic reactions as an attractive environmentally friendly solvent.1 Accordingly, several different reactions such as Diels-Alder cycloadditions,2 reductions and couplings of organic halides,3 cracking and rearrangements,4 hydrogenations, hydroformylation, and oxidation processes,1,5 and photochemical reactions6 are claimed to proceed in supercritical CO2 (scCO2). However, the poor solubilizing power of the scCO2 for many polar compounds may represent a severe limitation, especially for reactions involving ionic moieties. In the case of catalytic processes carried out with neutral or ionic complexes of transition metals, elegant solutions have been achieved following three different approaches: (i) the incorporation of “CO2-philic” fragments (e.g., perfluorinated groups) into the catalysts, either as ligands of the metal or in the counteranions,5a,7-9 (ii) the use of biphasic systems (scCO2-ethylene glycol, scCO2-water), and (iii) the use of surfactant-stabilized water/CO2 emulsions.11 When ionic or highly polar reagents are used, the introduction of polar cosolvents may overcome the solubility problem. In fact, under solid-liquid phase-transfer catalysis conditions (SL-PTC), nucleophilic displacements have been reported in scCO2, providing that acetone is present as a cosolvent for the PT-catalyst.12 Yet, reactions proceed at moderate rates (50 °C: after 48 h, 15-60% conversions). Similarly, the Glaser coupling of alkynes has been claimed in scCO2 in the presence of MeOH as a “polar modifier” which enhances the solubility of the reactive salts (CuCl2 and AcONa).13 As a phase-transfer solvent, scCO2 has been described in the extraction/methylation of chlorinated benzoates (ArCO2: Ar ) C6H3Cl2 and C6H2Cl3) from aqueous solutions:14 in this case, no cosolvents are required because of the high hydrophobic character of the nucleophiles. Nucleophilic displacements have also been reported in water/scCO2 microemulsions (w/c-me) prepared with fluorinated surfactants (perfluoropolyether ammonium carboxylates: PFPECO2NH4). More recently, electrogenerated radicals and cations have been stabilized in the water core of similar w/c-me (PFPE-phosphate).16 In scCO2, efficient Diels-Alder reactions and enzymatic esterifications of polar substrates have been claimed with the use of amorphous silica gel,17,18 whose promoting role, although not well understood, is explained through the adsorption of the reactants which come into closer contact to each other, on the silica surface. A related, but conceptually different approach can be conceived with supported onium salts as reagents: as reported by us,19,20different anions (I-, Br-, SCN-) paired to bulky onium cations immobilized on alumina or silica gel, undergo fast nucleophilic substitutions in the presence of nonpolar media (n-heptane or toluene). In this paper, we report for the first time that immobilized PT-agents provide also efficient anionic nucleophiles for reactions in scCO2.}, number={11}, journal={The Journal of Organic Chemistry}, publisher={American Chemical Society (ACS)}, author={DeSimone, Joseph and Selva, Maurizio and Tundo, Pietro}, year={2001}, month={Jun}, pages={4047–4049} } @article{powell_mccleskey_tumas_desimone_2001, title={Polymers with Multiple Ligand Sites for Metal Extractions in Dense-Phase Carbon Dioxide†}, volume={40}, ISSN={0888-5885 1520-5045}, url={http://dx.doi.org/10.1021/ie000811b}, DOI={10.1021/ie000811b}, abstractNote={We have synthesized a series of CO2-soluble polymeric extractants with multiple ligand sites for CO2-based metal extractions. The CO2-soluble polymers were prepared via free-radical copolymerization of a fluorinated acrylate with a series of acrylate- or styrene-based monomers functionalized with ligand sites or ligand precursors. These polymers have high solubility in CO2; up to 30 wt % of a polymer with 15 mol % of a ligand-based monomer can be solubilized in liquid CO2 at 25 °C at 140 bar. Copper and europium extractions have been performed with β-diketone- and phosphonate-functionalized polymers, respectively. Preliminary extractions with copper nitrate were carried out at ligand-to-metal ratios of 1:1 and 2.7:1, resulting in 25−37% and 59% efficiency, respectively, suggesting a ligand binding stoichiometry of 2 for efficient extraction. Europium luminescence studies demonstrate that europium is bound to the polymer along with four water molecules in the inner coordination sphere.}, number={5}, journal={Industrial & Engineering Chemistry Research}, publisher={American Chemical Society (ACS)}, author={Powell, Kimberly R. and McCleskey, T. Mark and Tumas, William and DeSimone, Joseph M.}, year={2001}, month={Mar}, pages={1301–1305} } @article{shi_desimone_kiserow_roberts_2001, title={Reaction Kinetics of the Solid-State Polymerization of Poly(bisphenol A carbonate) Facilitated by Supercritical Carbon Dioxide}, volume={34}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma011068h}, DOI={10.1021/ma011068h}, abstractNote={The kinetics of solid-state polymerization (SSP) of poly(bisphenol A carbonate) was investigated with supercritical CO2 (scCO2) as the sweep fluid. The CO2 flow rate and polymer particle size were chosen to ensure that the kinetics was controlled by the rate of the forward transesterification reaction, i.e., so that both external and internal phenol diffusion limitations were negligible. The forward reaction rate constants were determined between 90 and 135 °C, at CO2 pressures of 138, 207, and 345 bar. At a given temperature, the reaction rate was higher with scCO2 as the sweep fluid than with N2, especially at lower temperatures. The rate constant for the forward transesterification reaction increased with increasing CO2 pressure up to about 207 bar, at which point the rate constant was no longer sensitive to CO2 pressure. The activation energy decreased from 23.9 kcal/mol in N2 to 15.5, 11.6, and 11.4 kcal/mol at CO2 pressures of 138, 207, and 345 bar, respectively. The effect of scCO2 on the rate of p...}, number={22}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Shi, Chunmei and DeSimone, Joseph M. and Kiserow, Douglas J. and Roberts, George W.}, year={2001}, month={Oct}, pages={7744–7750} } @article{shi_gross_desimone_kiserow_roberts_2001, title={Reaction kinetics of the solid state polymerization of poly(bisphenol A carbonate)}, volume={34}, ISSN={["0024-9297"]}, DOI={10.1021/ma001942r}, abstractNote={The kinetics of solid-state polymerization (SSP) of poly(bisphenol A carbonate) was investigated with N2 as the sweep gas. The N2 flow rate and prepolymer particle size were chosen to eliminate the influence of both external and internal phenol diffusion, and to ensure that the kinetics was controlled by the rate of the forward transesterification reaction. The forward reaction rate constants were evaluated at different temperatures between 120 and 165 °C, and the activation energy for SSP of poly(bisphenol A carbonate) with N2 as the sweep gas was determined to be 99.6 kJ/mol. At each temperature, the polymer molecular weight increased with time, eventually reaching an asymptotic value. The asymptotic molecular weight increased with temperature. The glass transition temperature (Tg) of the polymer increased as the molecular weight increased. At lower reaction temperatures, Tg approaches the reaction temperature as the polymerization proceeds, and the achievable molecular weight appears to be limited by d...}, number={7}, journal={MACROMOLECULES}, author={Shi, CM and Gross, SM and DeSimone, JM and Kiserow, DJ and Roberts, GW}, year={2001}, month={Mar}, pages={2060–2064} } @article{hartshorn_maxwell_white_desimone_meyer_2001, title={Separation of Positional Isomers of Oxidation Catalyst Precursors}, volume={40}, ISSN={0020-1669 1520-510X}, url={http://dx.doi.org/10.1021/ic9911724}, DOI={10.1021/ic9911724}, abstractNote={A series of polypyridyl ruthenium complexes of the general formula [Ru(tpy)(bpy')Cl]+ where tpy is 2,2':6',2"-terpyridine and bpy' is 4-carboxy-4'-methyl-2,2'-bipyridine (4-CO2H-4'-Mebpy), a proline derviative (4-CO-Pra-(Boc)(OMe)-4'-Mebpy), or 4-((diethoxyphosphinyl)methyl)-4'-methyl-2,2'-bipyridine (4-CH2PO3Et2-4'-Mebpy) are prepared. For each complex, two isomers exist, and these are separated chromatographically. The structure of the hexafluorophosphate salt of cis-[Ru(tpy)(4-CO2H-4'-Mebpy)Cl]+, cis-1, is determined by X-ray crystallography. The salt crystallizes in the monoclinic space group Cc with a = 12.4778(6) A, b = 12.6086(6) A, c = 20.1215(9) A, beta = 107.08200(1) degrees, Z = 4, R = 0.058, and Rw = 0.072. The structures of the remaining complexes are assigned by 1H NMR comparisons with cis-1. The complexes are potentially important precursors for the incorporation of RuIV=O2+ oxidants into polymers or peptides or for their adsorption onto oxide surfaces. Preliminary electrochemical results for the isomers of [Ru(tpy)(4-CH2PO3H2-4'-Mebpy)(H2O)]2+, 4, adsorbed on ITO (In2O3:Sn) surfaces add support to a recently proposed electron-transfer mechanism involving cross-surface proton-coupled electron transfer.}, number={4}, journal={Inorganic Chemistry}, publisher={American Chemical Society (ACS)}, author={Hartshorn, Chris M. and Maxwell, Kimberly A. and White, Peter S. and DeSimone, Joseph M. and Meyer, Thomas J.}, year={2001}, month={Feb}, pages={601–606} } @article{nagai_tanaka_hirata_nakagawa_arnold_freeman_leroux_betts_desimone_digiano_2001, title={Solubility and diffusivity of sodium chloride in phase-separated block copolymers of poly(2-dimethylaminoethyl methacrylate), poly (1,1'-dihydroperfluorooctyl methacrylate) and poly(1,1,2,2-tetrahydroperfluorooctyl acrylate)}, volume={42}, ISSN={["0032-3861"]}, DOI={10.1016/S0032-3861(01)00549-3}, abstractNote={Solubility and diffusivity of sodium chloride were determined in a series of dense films of phase-separated diblock and triblock copolymers composed of poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) and either poly(1,1′-dihydroperfluorooctyl methacrylate (PFOMA) or poly(1,1,2,2-tetrahydroperfluorooctyl acrylate) (PTAN). As the content of hydrophilic PDMAEMA increases in PDMAEMA-b-PFOMA films, total water uptake increases. The salt partition coefficient of these films increases with increasing PDMAEMA content and weight fraction of water in the PDMAEMA domains. In contrast, salt diffusivity is not monotonically correlated with PDMAEMA content and effective hydration. Triblock copolymers exhibit different values of total water uptake, total hydration, salt partition, and diffusion coefficients than those of diblock copolymers (PDMAEMA-b-PFOMA) at the same PDMAEMA concentration. The total water uptake of PFOMA-b-PDMAEMA-b-PFOMA copolymers is lower than that of PDMAEMA-b-PFOMA, while water uptake of PTAN-b-PDMAEMA-b-PTAN films is higher than that of PDMAEMA-b-PFOMA. Salt partition and diffusion coefficients increase monotonically with the amount of freezing water in the hydrophilic domains, suggesting that the state of water in the phase-separated block copolymers is an important factor influencing their salt uptake and transport properties.}, number={25}, journal={POLYMER}, author={Nagai, K and Tanaka, S and Hirata, Y and Nakagawa, T and Arnold, ME and Freeman, BD and Leroux, D and Betts, DE and DeSimone, JM and DiGiano, FA}, year={2001}, month={Dec}, pages={9941–9948} } @article{wells_taylor_adam_desimone_farago_2001, title={Study of the Association of a Diblock Copolymer and Absorption of an Insoluble Homopolymer in CO2}, volume={34}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma002187k}, DOI={10.1021/ma002187k}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTStudy of the Association of a Diblock Copolymer and Absorption of an Insoluble Homopolymer in CO2Sharon L. Wells, Darlene Taylor, Mireille Adam, J. M. DeSimone, and Bela FaragoView Author Information Department of Chemistry, University of North Carolina at Chapel Hill, Venable Hall CB#3290, Chapel Hill, North Carolina 27599, and Institute Laue Langevin, B.P. 156, F-38042, Grenoble, France Cite this: Macromolecules 2001, 34, 18, 6161–6163Publication Date (Web):July 24, 2001Publication History Received22 December 2000Revised23 May 2001Published online24 July 2001Published inissue 1 August 2001https://pubs.acs.org/doi/10.1021/ma002187khttps://doi.org/10.1021/ma002187krapid-communicationACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views78Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Copolymers,Homopolymers,Micelles,Scattering,Solvents Get e-Alerts}, number={18}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Wells, Sharon L. and Taylor, Darlene and Adam, Mireille and DeSimone, J. M. and Farago, Bela}, year={2001}, month={Aug}, pages={6161–6163} } @misc{desimone_keiper_2001, title={Surfactants and self-assembly in carbon dioxide}, volume={5}, ISSN={["1879-0348"]}, DOI={10.1016/s1359-0286(00)00041-3}, abstractNote={Amphiphilic compounds have played a vital role in the emergence of carbon dioxide in both its liquid and supercritical states as a versatile, environmentally benign solvent. This review serves to describe recent efforts in three major areas of the field: (1) polymeric amphiphile self-assembly in carbon dioxide solutions, (2) use of surfactants as stabilizing agents for polymerizations, and (3) studies involving ‘small molecule’ surfactant assemblies in carbon dioxide.}, number={4}, journal={CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE}, author={DeSimone, JM and Keiper, JS}, year={2001}, month={Aug}, pages={333–341} } @inbook{carson_wells_desimone_2001, place={New York}, title={Surfactants for Supercritical and Near-Critical Fluids}, booktitle={Reactions and Synthesis in Surfactant Systems}, publisher={Marcel Dekker, Inc.}, author={Carson, T. and Wells, S.L. and DeSimone, J.M.}, editor={Texter, JohnEditor}, year={2001}, pages={129–143} } @article{gross_roberts_kiserov_desimone_2001, title={Synthesis of high molecular weight polycarbonate by solid-state polymerization}, volume={34}, ISSN={["1520-5835"]}, DOI={10.1021/ma001958h}, abstractNote={The solid-state polymerization (SSP) of small particles (20 μm) of poly(bisphenol A carbonate) resulted in high molecular weight material (Mw of 36 000 g/mol). Molecular weight distribution broaden...}, number={12}, journal={MACROMOLECULES}, author={Gross, SM and Roberts, GW and Kiserov, DJ and DeSimone, JM}, year={2001}, month={Jun}, pages={3916–3920} } @article{fleming_maxwell_desimone_meyer_papanikolas_2001, title={Ultrafast Excited-State Energy Migration Dynamics in an Efficient Light-Harvesting Antenna Polymer Based on Ru(II) and Os(II) Polypyridyl Complexes}, volume={123}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja016304i}, DOI={10.1021/ja016304i}, abstractNote={A detailed study of the excited state energy migration dynamics that take place within an assembly of Ru(II) and Os(II) polypyridyl complexes linked together through a polymer backbone is presented. The energy migration process is initiated by the photoexcitation of the metal-to-ligand charge transfer (MLCT) transition in one of the Ru(II) complexes and terminated by energy transfer to a lower energy Os(II) trap. Energy transfer sensitization of Os(II) can occur in a single step if the excited state is formed adjacent to a trap, or after a series of hops between isoenergetic rutheniums prior to reaching a trap. The dynamics of the energy transfer process are followed by monitoring the growth of Os(II) luminescence at 780 nm. The kinetics of the growth are complex and can be fit by a sum of two exponentials. This kinetic complexity arises both from the presence of a distribution of donor-acceptor distances and the variety of time scales by which Os(II) can be formed. We have augmented the time-resolved experiments with Monte Carlo simulations, which provide insight into the polymer array's structure and at the same time form the basis of a molecular-level description of the energy migration dynamics. The simulations indicate that the most probable Ru-->Os energy transfer time is approximately 400 ps while the time scale for Ru-->Ru hopping is approximately 1-4 ns. The time scale for Ru-->Ru hopping relative to its natural lifetime (1000 ns) suggests that this polymer system could be extended to considerably longer dimensions without an appreciable loss in its overall efficiency.}, number={42}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Fleming, Cavan N. and Maxwell, Kimberly A. and DeSimone, Joseph M. and Meyer, Thomas J. and Papanikolas, John M.}, year={2001}, month={Oct}, pages={10336–10347} } @article{bunyard_kadla_desimone_2001, title={Viscosity effects on the thermal decomposition of bis(perfluoro-2-N-propoxypropionyl) peroxide in dense carbon dioxide and fluorinated solvents}, volume={123}, ISSN={["0002-7863"]}, DOI={10.1021/ja0103344}, abstractNote={The thermal decomposition of the free-radical initiator bis(perfluoro-2-N-propoxyprionyl) peroxide (BPPP) was studied in dense carbon dioxide and a series of fluorinated solvents. For the fluorinated solvents, the observed first-order decomposition rate constants, k(obs), increased with decreasing solvent viscosity, suggesting a single-bond decomposition mechanism. The k(obs) values are comparatively larger in dense carbon dioxide and similar to the "zero-viscosity" rate constants extrapolated from the decomposition kinetics in the fluorinated solvents. The decomposition activation parameters demonstrate a compensation behavior of the activation enthalpy with the activation entropy upon change in solvent viscosity. Comparison of the change in activation parameter values upon change in solvent viscosity for BPPP with two additional initiators, acetyl peroxide (AP) and trifluoroacetyl peroxide (TFAP), further suggests that carbon dioxide exerts a very minimal influence on the decomposition mechanism of these initiators through solvent-cage effects.}, number={30}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Bunyard, WC and Kadla, JF and DeSimone, JM}, year={2001}, month={Aug}, pages={7199–7206} } @article{ye_wells_desimone_2001, title={Well-defined glycopolyrner amphiphiles for liquid and supercritical carbon dioxide applications}, volume={39}, ISSN={["0887-624X"]}, DOI={10.1002/pola.10018}, abstractNote={AbstractWell‐defined D‐glucose‐containing glycopolymers, poly(3‐O‐methacryloyl‐1,2 : 5,6‐di‐O‐isopropylidene‐D‐glucofuranose) (PMAIpGlc), and diblock copolymers of PMAIpGlc with poly(1,1‐dihydroperfluorooctyl methacrylate) (PFOMA) were synthesized by living anionic polymerization in THF at −78 °C with 1,1‐diphenylhexyllithium in the presence of lithium chloride. The resulting polymers were found to possess predictable molecular weights and very narrow molecular weight distributions (MWD, Mw/Mn ≤ 1.16). Removal of the acetal protective groups from the protected glycopolymer block copolymer was carried out using 90% trifluoroacetic acid at room temperature, yielding a hydrophilic block copolymer with pendant glucose moieties. Both protected (lipophilic/CO2‐philic) and deprotected (hydrophilic/CO2‐philic) fluorocopolymers were proved to be CO2 amphiphiles. Their solubility in CO2 was heavily influenced by the amphiphilic structure, such as the copolymer compositions and the polarities of sugar block. Light‐scattering studies showed that, after removal of the protective groups, the deprotected block copolymer formed aggregate structures in liquid CO2 with an average micellar size of 27 nm. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3841–3849, 2001}, number={21}, journal={JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY}, author={Ye, WJ and Wells, S and DeSimone, JM}, year={2001}, month={Nov}, pages={3841–3849} } @article{goodner_desimone_kiserow_roberts_2000, title={An equilibrium model for diffusion-limited solid-state polycondensation}, volume={39}, ISSN={["0888-5885"]}, DOI={10.1021/ie990648o}, abstractNote={A model for unsteady-state solid-state polycondensation (SSP) is developed and is applied to the polymerization of poly(bisphenol A carbonate) and poly(ethylene terephthalate) (PET). The model assumes that diffusion of the reaction condensate in the solid polymer is the rate-limiting step in the overall polymerization kinetics. Therefore, the reversible polycondensation reaction is at local equilibrium throughout the polymer particle at all times. The model is applicable to the three general types of step-growth polymerization:  AB, A2, and A2 + B2 polycondensation. Through comparison with the predictions of a full kinetic model for polycarbonate synthesis, it is demonstrated that the equilibrium model provides an upper bound on molecular weight and its rate of increase. Model predictions are also compared to experimental data for PET SSP. These comparisons show that the equilibrium model provides a useful tool for understanding the effects of temperature and particle size as well as for establishing a lo...}, number={8}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Goodner, MD and DeSimone, JM and Kiserow, DJ and Roberts, GW}, year={2000}, month={Aug}, pages={2797–2806} } @article{goodner_gross_desimone_roberts_kiserow_2001, title={Broadening of molecular-weight distribution in solid-state polymerization resulting from condensate diffusion}, volume={79}, ISSN={["0021-8995"]}, DOI={10.1002/1097-4628(20010131)79:5<928::AID-APP170>3.0.CO;2-X}, abstractNote={A kinetic model for the solid-state polymerization of poly(bisphenol A carbonate) in a single particle has been developed and used to investigate the broadening of molecular-weight distribution as a result of slow condensate diffusion. The model is based on melt-phase transesterification kinetics and Fickian diffusion of phenol, the condensate, in the amorphous regions of the semicrystalline particle. Model predictions compare favorably to experimental data. When diffusion is slow compared to reaction, a condensate concentration gradient is established. This gradient induces a molecular-weight gradient, which results in a broadened overall molecular-weight distribution with an overall polydispersity above the theoretical limit for homogenous step-growth polymerization. As the mass transfer resistance inside the particle is decreased, the average molecular weight increases faster with time, and the overall polydispersity decreases. A stoichiometric imbalance of end groups decreases the obtainable molecular weight but mitigates the deleterious effects of slow condensate diffusion. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 928–943, 2001}, number={5}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Goodner, MD and Gross, SM and Desimone, JM and Roberts, GW and Kiserow, DJ}, year={2001}, month={Jan}, pages={928–943} } @article{shultz_desimone_brookhart_2001, title={Cationic Four- and Five-Coordinate Nickel(II) Complexes:  Insights into the Nickel(II)-Catalyzed Copolymerization of Ethylene and Carbon Monoxide}, volume={20}, ISSN={0276-7333 1520-6041}, url={http://dx.doi.org/10.1021/om0008023}, DOI={10.1021/om0008023}, abstractNote={Using the dppp-derived Ni(II) catalyst system 2, several four- and five-coordinate intermediates relevant to the alternating copolymerization of ethylene and carbon monoxide have been characterized. In addition, the activation barriers for the migratory insertion steps corresponding to chain growth have been determined to be at or below ca. 10 kcal/mol, indicating that a strongly stabilized catalyst resting state is most likely responsible for the low activity of 2 for copolymerization.}, number={1}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Shultz, C. Scott and DeSimone, Joseph M. and Brookhart, Maurice}, year={2001}, month={Jan}, pages={16–18} } @article{charpentier_desimone_roberts_2000, title={Continuous precipitation polymerization of vinylidene fluoride in supercritical carbon dioxide: Modeling the rate of polymerization}, volume={39}, ISSN={["0888-5885"]}, DOI={10.1021/ie000354z}, abstractNote={The kinetics of the surfactant-free precipitation polymerization of vinylidene fluoride (VF2) in supercritical carbon dioxide have been studied in a continuous stirred autoclave. Diethyl peroxydicarbonate was used as the free-radical initiator. The stirring rate and agitator design had no effect on the rate of polymerization (Rp) or on the weight-average molecular weight (Mw) of the formed poly(vinylidene fluoride) (PVDF). The fractional conversion of VF2 ranged from 7 to 26%, and Rp was as high as 27 × 10-5 mol/L·s at 75 °C and at a VF2 feed concentration of 2.5 mol/L. The PVDF polymer was collected as a dry, “free-flowing” powder and had Mw's up to 150 kg/mol and melt flow indices as low as 3.0 at 230 °C. Homogeneous, free-radical kinetics provided a reasonable basis for describing the rate of polymerization, despite the heterogeneous nature of the system. The order of the reaction with respect to the monomer was found to be 1.0, and the order with respect to the initiator was 0.5. The experimental data...}, number={12}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Charpentier, PA and DeSimone, JM and Roberts, GW}, year={2000}, month={Dec}, pages={4588–4596} } @article{triolo_triolo_triolo_betts_mcclain_de simone_steytler_wignall_demé_heenan_2000, title={Critical micellisation density: a SAS structural study of the unimer–aggregate transition of block-copolymers in supercritical CO2}, volume={33}, ISSN={0021-8898}, url={http://dx.doi.org/10.1107/s0021889899013539}, DOI={10.1107/s0021889899013539}, abstractNote={In this paper we report a SANS investigation of micelle formation by fluorocarbon-hydrocarbon block copolymers in supercritical CO2 (scCO2) at 313K. A sharp unimer-micelle transition is obtained due to the tuning of the solvating ability of scCO2 by profiling pressure. At high pressure the copolymer is in a monomeric state with a random coil structure. By lowering the pressure aggregates are formed with the hydrocarbon segments forming the core and the fluorocarbon segments forming the corona of spherical aggregates. This aggregateunimer transition is driven by the gradual penetration of CO2 molecules toward the core of the aggregate and is critically related to the density of the solvent, thus suggesting the definition of a critical micellisation density (CMD).}, number={3}, journal={Journal of Applied Crystallography}, publisher={International Union of Crystallography (IUCr)}, author={Triolo, F. and Triolo, A. and Triolo, R. and Betts, D.E. and McClain, J.B. and De Simone, J.M. and Steytler, D.C. and Wignall, G.D. and Demé, B. and Heenan, R.K.}, year={2000}, month={Jun}, pages={641–644} } @article{triolo_triolo_lo celso_betts_mcclain_desimone_wignall_triolo_2000, title={Critical micellization density: A small-angle-scattering structural study of the monomer-aggregate transition of block copolymers in supercritical CO2}, volume={62}, ISSN={1063-651X 1095-3787}, url={http://dx.doi.org/10.1103/physreve.62.5839}, DOI={10.1103/physreve.62.5839}, abstractNote={In this paper we report a small-angle neutron-scattering investigation of micelle formation by the fluorocarbon-hydrocarbon block copolymer, polyvinyl acetate-b-poly (1,1,2, 2-tetrahydroperfluoro-octyl acrylate) in supercritical CO2 (scCO(2)) at 313 K. At high pressure the copolymer is in a monomeric state with a random coil structure, while at low pressure the polymer forms spherical aggregates stable in a wide range of thermodynamic conditions. By profiling pressure, a sharp monomer-micelle transition is obtained due to the tuning of the solvating ability of scCO(2). We confirm the previous finding that this aggregate-monomer transition is driven by the gradual penetration of CO2 molecules toward the core of the aggregate and is critically related to the density of the solvent, thus giving additional support to the concept of a critical micellization density reported earlier on a similar polymer.}, number={4}, journal={Physical Review E}, publisher={American Physical Society (APS)}, author={Triolo, A. and Triolo, F. and Lo Celso, F. and Betts, D. E. and McClain, J. B. and DeSimone, J. M. and Wignall, G. D. and Triolo, R.}, year={2000}, month={Oct}, pages={5839–5842} } @article{charpentier_desimone_roberts_2000, title={Decomposition of polymerisation initiators in supercritical CO2: a novel approach to reaction kinetics using a CSTR}, volume={55}, ISSN={["0009-2509"]}, DOI={10.1016/s0009-2509(00)00148-2}, abstractNote={A novel method for simultaneous determination of the decomposition rate constant, kD, and the initiator efficiency, f, of a free-radical polymerisation initiator has been developed. The decomposition is carried out in a continuous-stirred-tank reactor (CSTR) in the presence of a radical scavenger. Mass balances for the initiator and the scavenger show that both f and kD can be determined from a set of constant-temperature experiments with a varying reactor mean residence time. Experiments were conducted in supercritical carbon dioxide (scCO2) using diethyl peroxydicarbonate (DEPDC) as the free-radical initiator and galvinoxyl as the free-radical scavenger. The decomposition of DEPDC was first-order between 338 and 358 K. The activation energy, EA, was 132 kJ/mol, the pre-exponential factor, AD, was 6.3×1016 s−1, and the initiator efficiency, f, was 0.6. These values are similar to those reported in the literature for DEPDC decomposition in traditional organic solvents. Varying the carbon dioxide pressure between 240 and 310 bar at 348 K had no effect on the value of kD. Transition state theory predicted no significant effect of pressure or solvent composition on the initiator decomposition rate constant.}, number={22}, journal={CHEMICAL ENGINEERING SCIENCE}, author={Charpentier, PA and DeSimone, JM and Roberts, GW}, year={2000}, month={Nov}, pages={5341–5349} } @article{carson_lizotte_desimone_2000, title={Dispersion Polymerization of 1-Vinyl-2-pyrrolidone in Supercritical Carbon Dioxide}, volume={33}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma991222o}, DOI={10.1021/ma991222o}, abstractNote={ADVERTISEMENT RETURN TO ISSUECommunication to the...Communication to the EditorNEXTDispersion Polymerization of 1-Vinyl-2-pyrrolidone in Supercritical Carbon DioxideTerri Carson, Jeremy Lizotte, and Joseph M. DesimoneView Author Information Department of Chemistry, University of North Carolina at Chapel Hill, Venable and Kenan Laboratories, CB# 3290, Chapel Hill, North Carolina 27599, and Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905 Cite this: Macromolecules 2000, 33, 6, 1917–1920Publication Date (Web):March 2, 2000Publication History Received23 July 1999Revised9 January 2000Published online2 March 2000Published inissue 1 March 2000https://pubs.acs.org/doi/10.1021/ma991222ohttps://doi.org/10.1021/ma991222orapid-communicationACS PublicationsCopyright © 2000 American Chemical SocietyRequest reuse permissionsArticle Views456Altmetric-Citations59LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Colloids,Monomers,Polymer particles,Polymerization,Polymers Get e-Alerts}, number={6}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Carson, Terri and Lizotte, Jeremy and Desimone, Joseph M.}, year={2000}, month={Mar}, pages={1917–1920} } @article{shiho_desimone_2000, title={Dispersion polymerization of 2-hydroxyethyl methacrylate in supercritical carbon dioxide}, volume={38}, DOI={10.1002/1099-0518(20001015)38:20<3783::AID-POLA90>3.0.CO;2-X}, abstractNote={Herein we report a successful dispersion polymerization of 2-hydroxyethyl methacrylate (HEMA) in a carbon dioxide continuous phase with a block copolymer consisting of polystyrene and poly(1,1-dihydroperfluorooctyl acrylate) as a stabilizer. Poly(2-hydroxyethyl methacrylate) was effectively emulsified in carbon dioxide with the amphiphilic diblock copolymer surfactant, and the successful stabilization of the polymerization simultaneously gave spherical particles in the submicrometer range with relatively narrow particle size distributions. The initial concentrations of HEMA and the stabilizer and the pressure had substantial effects on the size of the colloidal particles. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3783–3790, 2000}, number={20}, journal={Journal of Polymer Science. Part A, Polymer Chemistry}, author={Shiho, H. and Desimone, J. M.}, year={2000}, pages={3783–3790} } @article{shiho_desimone_2000, title={Dispersion polymerization of acrylonitrile in supercritical carbon dioxide}, volume={33}, ISSN={["0024-9297"]}, DOI={10.1021/ma990737c}, abstractNote={Herein we report the successful dispersion polymerization of acrylonitrile in carbon dioxide using a block copolymer consisting of polystyrene and poly(1,1-dihydroperfluorooctyl acrylate) as a stabilizer. Submicron-sized polyacrylonitrile particles were obtained. The initial concentrations of acrylonitrile and the stabilizer and the reaction pressure had some effects on the resulting size of the colloidal particles.}, number={5}, journal={MACROMOLECULES}, author={Shiho, H and DeSimone, JM}, year={2000}, month={Mar}, pages={1565–1569} } @article{shiho_desimone_2000, title={Dispersion polymerization of styrene in supercritical carbon dioxide utilizing random copolymers containing a fluorinated acrylate for preparing micron-size polystyrene particles}, volume={38}, number={7}, journal={Journal of Polymer Science. Part A, Polymer Chemistry}, author={Shiho, H. and Desimone, J. M.}, year={2000}, month={Apr}, pages={1146–1153} } @article{young_desimone_2000, title={Frontiers in green chemistry utilizing carbon dioxide for polymer synthesis and applications}, volume={72}, ISSN={1365-3075 0033-4545}, url={http://dx.doi.org/10.1351/pac200072071357}, DOI={10.1351/pac200072071357}, abstractNote={Abstract In the last ten years, there has been incredible growth in research involving the use of carbon dioxide as an environmentally benign solvent. This article will highlight polymer synthesis, characterization, and applications in CO2 and place this research in the context of both green chemistry and the latest developments in CO2 technology.}, number={7}, journal={Pure and Applied Chemistry}, publisher={Walter de Gruyter GmbH}, author={Young, Jennifer L. and DeSimone, Joseph M.}, year={2000}, month={Jan}, pages={1357–1363} } @article{royer_gay_desimone_khan_2000, title={High-pressure rheology of polystyrene melts plasticized with CO2: Experimental measurement and predictive scaling relationships}, volume={38}, number={23}, journal={Journal of Polymer Science. Part B, Polymer Physics}, author={Royer, J. R. and Gay, Y. J. and Desimone, J. M. and Khan, S. A.}, year={2000}, month={Dec}, pages={3168–3180} } @article{shultz_ledford_desimone_brookhart_2000, title={Kinetic Studies of Migratory Insertion Reactions at the (1,3-Bis(diphenylphosphino)propane)Pd(II) Center and Their Relationship to the Alternating Copolymerization of Ethylene and Carbon Monoxide}, volume={122}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja994251n}, DOI={10.1021/ja994251n}, abstractNote={The quantitative details of three migratory insertion processes relevant to the copolymerization of ethylene and CO by the highly active (dppp)Pd(II)-based catalyst have been examined. Cationic Pd(II) intermediates generated at low temperatures and characterized by 1H, 13C and 31P NMR spectroscopy include (dppp)Pd(C2H4)(R)+ (R = −CH3, −CH2CH3), 6 and 7; (dppp)Pd(CO)(R)+ (R = −CH3, −CH2CH3), 8 and 11; and (dppp)Pd(C2H4)(COCH3)+, 13. Kinetic studies of the migratory insertion reactions of these species established the following activation parameters:  6(ΔG⧧ = 16.6(1) kcal/mol (−45.6 °C), ΔH⧧= 15.2(7) kcal/mol, ΔS⧧ = −6.2(2.9) eu), 7(ΔG⧧ = 16.3(1) kcal/mol (−33.7 °C), ΔH⧧ = 15.9(8) kcal/mol, ΔS⧧ = −1.6(3.7) eu), 8(ΔG⧧ = 14.8(1) kcal/mol (−81.7 °C), ΔH⧧ = 14.8(7) kcal/mol, ΔS⧧ = 0.1(3.0) eu), 11(ΔG⧧ = 13.4(1) kcal/mol (−94.2 °C)), 13(ΔG⧧ = 12.3(1) kcal/mol (−103.1 °C)). On the basis of the relative binding affinities of CO and C2H4 to the Pd(II) center and the relative rates of alkyl to CO and alkyl to ethyle...}, number={27}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Shultz, C. Scott and Ledford, John and DeSimone, Joseph M. and Brookhart, Maurice}, year={2000}, month={Jul}, pages={6351–6356} } @misc{carbonel_desimone_henon_2000, title={Method and compositions for protecting civil infrastructure}, volume={6,127,000}, number={2000 Oct. 3}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonel, R. G. and DeSimone, J. M. and Henon, F. E.}, year={2000}, month={Oct} } @misc{carbonell_desimone_novick_2000, title={Method for meniscus coating with liquid carbon}, volume={6,497,921}, number={2002 Dec. 24}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M. and Novick, B. J.}, year={2000}, month={Jun} } @misc{carbonell_desimone_novick_2000, title={Method for meniscus coating with liquid carbon dioxide}, volume={6,083,565}, number={2000 July 4}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M. and Novick, B. J.}, year={2000}, month={Jul} } @article{sykora_maxwell_desimone_meyer_2000, title={Mimicking the antenna-electron transfer properties of photosynthesis}, volume={97}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.97.14.7687}, DOI={10.1073/pnas.97.14.7687}, abstractNote={ A molecular assembly based on derivatized polystyrene is described, which mimics both the light-harvesting and energy-conversion steps of photosynthesis. The system is unique in that the two key parts of a photosynthetic system are incorporated in a functional assembly constructed from polypyridine complexes of Ru II . This system is truly artificial, as none of the components used in construction of the assembly are present in a natural photosynthetic system. Quantitative evaluation of the energy and electron transfer dynamics after transient irradiation by visible light offers important insights into the mechanisms of energy transport and electron transfer that lead to photosynthetic light-to-chemical energy conversion. }, number={14}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Sykora, M. and Maxwell, K. A. and DeSimone, J. M. and Meyer, T. J.}, year={2000}, month={Jul}, pages={7687–7691} } @misc{taylor_carbonell_desimone_2000, title={Opportunities for pollution prevention and energy efficiency enabled by the carbon dioxide technology platform}, volume={25}, ISSN={["1056-3466"]}, DOI={10.1146/annurev.energy.25.1.115}, abstractNote={ ▪ Abstract  Various applications using carbon dioxide (CO2) have developed within the last decade and, if current trends continue, the CO2 technology platform could emerge as the most commonly used solvent in the twenty-first century. An environmentally friendly platform that is wrapped in a successful business format with apparent implications for people and their communities is most likely to endure. Does the CO2 technology platform meet the criteria for becoming a sustainable enterprise? Utilizing CO2 as an alternative solvent in conventional processes has the potential to favorably impact the environment and our communities. There are, however, several barriers to adopting CO2-based applications. Several concepts as well as obstacles to adopting the carbon dioxide technology platform are highlighted in this chapter. }, journal={ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT}, author={Taylor, DK and Carbonell, R and DeSimone, JM}, year={2000}, pages={115–146} } @article{shiho_desimone_2000, title={Preparation of silicone-graft copolymers by homogeneous radical copolymerization in supercritical carbon dioxide}, volume={38}, ISSN={["0887-624X"]}, DOI={10.1002/(sici)1099-0518(20000401)38:7<1139::aid-pola12>3.0.co;2-3}, abstractNote={Copolymerizations of 1,1-dihydroperfluorooctyl methacrylate (FOMA; M1) and methacryloxypropyl-terminated polydimethylsiloxane [M-PDMS (Mn = 5.9 K); M2] and homopolymerization of M-PDMS in supercritical CO2 are described. The homopolymerization of M-PDMS proceeded homogeneously without difficulty to produce oligomers (Mn = 30 K). The copolymerizations of FOMA and M-PDMS also proceeded homogeneously over a wide monomer feed ratio. The ratio of M-PDMS incorporated into the copolymer obtained was almost equal to the monomer feed ratio even up to the high conversion. The reactivity ratio r1 was determined to be 1.66. DSC examination of the copolymers indicated a microphase-separated morphology consisting of poly-FOMA (PFOMA) and PDMS domains for all copolymer compositions. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1139–1145, 2000}, number={7}, journal={JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY}, author={Shiho, H and DeSimone, JM}, year={2000}, month={Apr}, pages={1139–1145} } @article{triolo_arrighi_triolo_migliardo_magazù_mcclain_betts_desimone_middendorf_2000, title={QENS from polymer aggregates in supercritical CO2}, volume={276-278}, ISSN={0921-4526}, url={http://dx.doi.org/10.1016/s0921-4526(99)01500-8}, DOI={10.1016/s0921-4526(99)01500-8}, abstractNote={Abstract We report QENS measurements from PS-b-PFOA aggregates in supercritical CO2. Line shapes are dominated by localized diffusive modes and segmental dynamics of the anchored, finite-length PFOA chains. For Q⩽0.6 A−1, we obtain effective diffusion coefficients of ≅0.8 10−6 cm2/s. At higher Q, a single component is not sufficient as shown by excess intensity on the flanks. For Q⩾1.5 A−1, the wings reflect contributions due to a distribution of faster, more localized chain modes.}, journal={Physica B: Condensed Matter}, publisher={Elsevier BV}, author={Triolo, R and Arrighi, V and Triolo, A and Migliardo, P and Magazù, S and McClain, J.B and Betts, D and DeSimone, J.M and Middendorf, H.D}, year={2000}, month={Mar}, pages={386–387} } @article{shiho_desimone_2000, title={Radical polymerizations of a silicone-containing acrylic monomer in supercritical carbon dioxide}, volume={38}, ISSN={["0887-624X"]}, DOI={10.1002/1099-0518(20000901)38:17<3100::AID-POLA110>3.0.CO;2-#}, number={17}, journal={JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY}, author={Shiho, H and DeSimone, JM}, year={2000}, month={Sep}, pages={3100–3105} } @article{smith_maxwell_desimone_meyer_palmer_2000, title={Step-Scan FTIR Time-Resolved Spectroscopy Study of Excited-State Dipole Orientation in Soluble Metallopolymers}, volume={39}, ISSN={0020-1669 1520-510X}, url={http://dx.doi.org/10.1021/ic990819h}, DOI={10.1021/ic990819h}, abstractNote={Step-scan FTIR time-resolved spectroscopy (S2FTIR TRS) in acetonitrile-d3 has been used to probe the acceptor ligand in metal-to-ligand charge transfer (MLCT) excited states of amide-substituted polypyridyl complexes of RuII and in analogues appended to polystyrene. On the basis of ground-to-excited state shifts in v(C = O) of -31 cm-1 for the amide group in [RuII(bpy)2(bpyCONHEt')]2+ (bpyCONHEt' = 4'-methyl-2,2'-bipyridine-4-carboxamide-Et'; Et' = -CH2CH2BzCH2CH3) (1) and in the derivatized polystyrene abbreviated [PS-[CH2-CH2NHCObpy-RuII(bpy)2]20]40+ (3), the excited-state dipole is directed toward the amide-containing pyridyl group in the polymer side chain. Smaller shifts in v(C = O) of -17 cm-1 in [RuII(4,4'-(CONEt2)2bpy)2-(bpyCONHEt')]2+ (2) and in the derivatized polystyrene abbreviated [PS-[CH2CH2NHCObpy-RuII(4,4'-(CONEt2)2bpy)2]20]40+ (4) indicate that the excited-state dipole is directed toward one of the diamide bpy ligands. The nearly identical results for 1 and 3 and for 2 and 4 show that the molecular and electronic structures of the monomer excited states are largely retained in the polymer samples. These conclusions about dipole orientation in the polymers are potentially of importance in understanding intrastrand energy transfer dynamics. The excited-state dipole in 3 is oriented in the direction of the covalent link to the polymer backbone, and toward nearest neighbors. In 4, it is oriented away from the backbone.}, number={5}, journal={Inorganic Chemistry}, publisher={American Chemical Society (ACS)}, author={Smith, Gregory D. and Maxwell, Kimberly A. and DeSimone, Joseph M. and Meyer, Thomas J. and Palmer, Richard A.}, year={2000}, month={Mar}, pages={893–898} } @article{triolo_triolo_triolo_steytler_lewis_heenan_wignall_desimone_2000, title={Structure of diblock copolymers in supercritical carbon dioxide and critical micellization pressure}, volume={61}, ISSN={1063-651X 1095-3787}, url={http://dx.doi.org/10.1103/physreve.61.4640}, DOI={10.1103/physreve.61.4640}, abstractNote={This paper reports a small angle neutron scattering investigation of micelle formation by fluorocarbon-hydrocarbon block copolymers in supercritical CO2(sc-CO2) at 65 degrees C. A sharp unimer-micelle transition is obtained due to the tuning of the solvating ability of sc-CO2 by profiling pressure, so that the block copolymer, in a semidilute solution, finds sc-CO2 a good solvent at high pressure and a poor solvent at low pressure. At high pressure the copolymer is in a monomeric state with a random coil structure. However, on lowering the pressure, aggregates are formed with a structure similar to aqueous micelles with the hydrocarbon segments forming the core and the fluorocarbon segments forming the corona of the micelle. This unimer-aggregate transition is driven by the gradual elimination of CO2 molecules solvating the hydrocarbon segments of the polymer. Comparison of these results with related data on the same polymer at different temperatures indicates that the transition is critically related to the density of the solvent. This suggests the definition of a critical micellization density, to our knowledge a new concept in colloid chemistry.}, number={4}, journal={Physical Review E}, publisher={American Physical Society (APS)}, author={Triolo, R. and Triolo, A. and Triolo, F. and Steytler, D. C. and Lewis, C. A. and Heenan, R. K. and Wignall, G. D. and DeSimone, J. M.}, year={2000}, month={Apr}, pages={4640–4643} } @article{ye_desimone_2000, title={Synthesis of Sugar-Containing Amphiphiles for Liquid and Supercritical Carbon Dioxide}, volume={39}, ISSN={0888-5885 1520-5045}, url={http://dx.doi.org/10.1021/ie000184q}, DOI={10.1021/ie000184q}, abstractNote={Liquid and/or supercritical carbon dioxide as a useful processing fluid is limited by its inability to solubilize highly polar compounds. This problem can be alleviated by the addition of CO2-philic amphiphiles. Our primary objective herein is to design and synthesize novel materials that have both strong polar moieties and highly CO2-philic segments. Sugar-containing hydrophobic/hydrophilic fluorinated copolymers were synthesized by free-radical polymerization. The degree of solubility of the amphiphiles in CO2 was found to be heavily influenced by the amphiphilic structure, including the polarity of the sugar head (acetal protected and deprotected), and the fraction of CO2-philic groups. We also found that the presence of water in the CO2 phase could decrease the solubility of the hydrophilic copolymer. The dispersion polymerization of 2-hydroxyethyl methacrylate in CO2 was tested by using the hydrophilic amphiphile as a stabilizer. Spherical particles in the submicron size range were obtained.}, number={12}, journal={Industrial & Engineering Chemistry Research}, publisher={American Chemical Society (ACS)}, author={Ye, Weijun and DeSimone, Joseph M.}, year={2000}, month={Dec}, pages={4564–4566} } @article{xia_johnson_gaynor_matyjaszewski_desimone_1999, title={Atom Transfer Radical Polymerization in Supercritical Carbon Dioxide}, volume={32}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9900380}, DOI={10.1021/ma9900380}, abstractNote={Atom transfer radical polymerization (ATRP) has been successfully carried out in supercritical carbon dioxide (scCO2) for the polymerization of fluorinated (meth)acrylates. In particular, well-controlled polymerizations have been obtained with the use of a fluoroalkyl-substituted 2,2‘-bipyridine ligand. Block copolymers comprised of fluorinated (meth)acrylates and poly(MMA) (MMA = methyl methacrylate) or poly(DMAEMA) (DMAEMA = 2-(dimethylamino)ethyl methacrylate) were produced in scCO2 by ATRP. In addition, the dispersion polymerization of MMA using ATRP in scCO2 in the presence of a fluorinated polymeric surfactant stabilizer was successfully carried out to yield poly(MMA) latex particles with controlled molecular weight and a narrow molecular weight distribution.}, number={15}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Xia, Jianhui and Johnson, Terri and Gaynor, Scott G. and Matyjaszewski, Krzysztof and DeSimone, Joseph}, year={1999}, month={Jul}, pages={4802–4805} } @article{royer_desimone_khan_1999, title={Carbon dioxide-induced swelling of poly( dimethylsiloxane)}, volume={32}, ISSN={["0024-9297"]}, DOI={10.1021/ma9904518}, abstractNote={A new experimental device is used to monitor in situ the swelling behavior of poly(dimethylsiloxane) melts in contact with supercritical carbon dioxide. The effects of pressure, temperature, and sample molecular weight on the kinetics and extent of swelling are examined using this experimental technique. The swelling kinetics of all polymer samples exhibit two distinct regimes:  an initial region of large swelling in which the diffusion of CO2 into the polymer follow Fickian behavior and a subsequent region of small volume increase asymptotic to an equilibrium swelling value. Diffusion coefficients of CO2, obtained from the initial swelling kinetics data, are found to be relatively insensitive to pressure, increase with temperature, and decrease with polymer molecular weight with the latter exhibiting a power-law dependence with an exponent of ∼−2. The extent of swelling increases with both pressure and molecular weight but exhibits different trends with temperature depending on system pressure. For press...}, number={26}, journal={MACROMOLECULES}, author={Royer, JR and DeSimone, JM and Khan, SA}, year={1999}, month={Dec}, pages={8965–8973} } @article{charpentier_kennedy_desimone_roberts_1999, title={Continuous Polymerizations in Supercritical Carbon Dioxide:  Chain-Growth Precipitation Polymerizations}, volume={32}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma990377t}, DOI={10.1021/ma990377t}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTContinuous Polymerizations in Supercritical Carbon Dioxide: Chain-Growth Precipitation PolymerizationsP. A. Charpentier, K. A. Kennedy, J. M. DeSimone, and G. W. RobertsView Author Information Department of Chemical Engineering, North Carolina State University, Box #7095, Raleigh, North Carolina 27695-7905, and Department of Chemistry, University of North CarolinaChapel Hill, Venable and Kenan Laboratories, CB#3290, Chapel Hill, North Carolina 27599 Cite this: Macromolecules 1999, 32, 18, 5973–5975Publication Date (Web):August 12, 1999Publication History Received12 March 1999Published online12 August 1999Published inissue 1 September 1999https://pubs.acs.org/doi/10.1021/ma990377thttps://doi.org/10.1021/ma990377trapid-communicationACS PublicationsCopyright © 1999 American Chemical SocietyRequest reuse permissionsArticle Views371Altmetric-Citations69LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Gel permeation chromatography,Monomers,Polymerization,Polymers,Precipitation Get e-Alerts}, number={18}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Charpentier, P. A. and Kennedy, K. A. and DeSimone, J. M. and Roberts, G. W.}, year={1999}, month={Sep}, pages={5973–5975} } @article{triolo_triolo_triolo_londono_wignall_mcclain_betts_wells_samulski_desimone_2000, title={Critical Micelle Density for the Self-Assembly of Block Copolymer Surfactants in Supercritical Carbon Dioxide}, volume={16}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la990140q}, DOI={10.1021/la990140q}, abstractNote={The parameters which influence the self-assembly of molecules in solution include the temperature and solvent quality, and this study illustrates the use of these variables to regulate the degree of association of block copolymer amphiphiles in highly compressible supercritical carbon dioxide. Small-angle neutron scattering (SANS) has been used to examine the association behavior of a block copolymer containing a CO2-phobic moiety, poly(vinyl acetate), and a CO2-philic block, poly(1,1-dihydroperfluoro-octylacrylate). By adjustment of the density of the medium through pressure and temperature profiling, the self-assembly can be reversibly controlled from unimers to core−shell spherical micelles and this establishes a critical micelle density (CMD), a phenomenon distinctive of highly compressible fluids, such as supercritical CO2. Mathematical modeling of the data in terms of core−shell micelle structures permits a detailed description of the structure and the degree of swelling (penetration) of the solvent...}, number={2}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Triolo, F. and Triolo, A. and Triolo, R. and Londono, J. D. and Wignall, G. D. and McClain, J. B. and Betts, D. E. and Wells, S. and Samulski, E. T. and DeSimone, J. M.}, year={2000}, month={Jan}, pages={416–421} } @article{gross_roberts_kiserow_desimone_2000, title={Crystallization and solid-state polymerization of poly(bisphenol A carbonate) facilitated by supercritical CO2}, volume={33}, ISSN={["1520-5835"]}, DOI={10.1021/ma990901w}, abstractNote={Poly(bisphenol A carbonate) was synthesized by solid-state polymerization (SSP) using supercritical CO2 to induce crystallinity in low molecular weight polycarbonate beads. The CO2-induced crystallization was studied as a function of time, temperature, molecular weight, and pressure. There was an optimum temperature for crystallization which depended on the molecular weight of the polymer. The molecular weight and percent crystallinity of the polymer produced by SSP were determined as a function of time and radial position in the bead. The molecular weight and percent crystallinity were strong functions of the particle radius, probably because of the slow diffusion of phenol out of the polymer particles. Nitrogen and supercritical CO2 were used as sweep fluids for the SSP process. The polymerization rate was always higher in supercritical CO2 at otherwise comparable conditions. We hypothesize that supercritical CO2 plasticizes the amorphous regions of the polymer, thereby increasing chain mobility and the...}, number={1}, journal={MACROMOLECULES}, author={Gross, SM and Roberts, GW and Kiserow, DJ and DeSimone, JM}, year={2000}, month={Jan}, pages={40–45} } @misc{desimone_wei_romack_1999, title={Fluorination in liquid or supercritical carbon dioxide}, volume={6,426,391}, number={2002 Jul. 30}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Wei, H.-C. and Romack, T. J.}, year={1999}, month={May} } @article{maxwell_sykora_desimone_meyer_2000, title={One-Pot Synthesis and Characterization of a Chromophore−Donor−Acceptor Assembly}, volume={39}, ISSN={0020-1669 1520-510X}, url={http://dx.doi.org/10.1021/ic990512i}, DOI={10.1021/ic990512i}, abstractNote={The acid-functionalized tris-heteroleptic chromophore--donor--acceptor assembly [RuII(bpyCOOH)(bpyCH2PTZ)(bpyCH2MV2+)](PF6)4]4+ (1) (bpyCOOH = 4'-methyl-2,2'-bipyridine-4-carboxylic acid; bpyCH2PTZ = 10-((4'-methyl-2,2'-bipyridin-4-yl)methyl)phenothiazine; bpyCH2MV2+ = 1-((4'-methyl-2,2'-bipyridin-4-yl)methyl)-1'-methyl- 4,4'-bipyridinediium) was synthesized in a one-pot reaction by careful selection of the order of ligand addition to RuCl2(DMSO)4 (DMSO = dimethyl sulfoxide). The success of this method was based upon separation and isolation of 1 from mixtures containing ligand-scrambled products by cation exchange chromatography. Metal-to-ligand charge-transfer (MLCT) excitation in acetonitrile at 464 nm was followed by intramolecular electron transfer to give a redox-separated state [RuII(bpyCOOH)(bpyCH2PTZ.+)(bpyCH2MV.+)]4+ with an efficiency of eta RS = 0.35 +/- 0.05.}, number={1}, journal={Inorganic Chemistry}, publisher={American Chemical Society (ACS)}, author={Maxwell, Kimberly A. and Sykora, Milan and DeSimone, Joseph M. and Meyer, Thomas J.}, year={2000}, month={Jan}, pages={71–75} } @article{bunyard_romack_desimone_1999, title={Perfluoropolyether Synthesis in Liquid Carbon Dioxide by Hexafluoropropylene Photooxidation}, volume={32}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma981588l}, DOI={10.1021/ma981588l}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTPerfluoropolyether Synthesis in Liquid Carbon Dioxide by Hexafluoropropylene PhotooxidationW. Clayton Bunyard, Timothy J. Romack, and Joseph M. DeSimoneView Author Information Department of Chemistry, University of North Carolina at Chapel Hill, CB #3290, Venable and Kenan Laboratories, Chapel Hill, North Carolina 27599-3290 Cite this: Macromolecules 1999, 32, 24, 8224–8226Publication Date (Web):November 10, 1999Publication History Received9 October 1998Revised4 October 1999Published online10 November 1999Published inissue 1 November 1999https://pubs.acs.org/doi/10.1021/ma981588lhttps://doi.org/10.1021/ma981588lrapid-communicationACS PublicationsCopyright © 1999 American Chemical SocietyRequest reuse permissionsArticle Views589Altmetric-Citations24LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Inorganic carbon compounds,Oxides,Phenyls,Photooxidation,Solvents Get e-Alerts}, number={24}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Bunyard, W. Clayton and Romack, Timothy J. and DeSimone, Joseph M.}, year={1999}, month={Nov}, pages={8224–8226} } @inbook{davidson_desimone_1999, place={Weinheim, Germany}, title={Polymerizations in Dense Carbon Dioxide}, DOI={10.1002/9783527613687.ch15}, abstractNote={Chapter 15 Polymerizations in Dense Carbon Dioxide Tammy A. Davidson, Tammy A. DavidsonSearch for more papers by this authorJoseph M. Desimone, Joseph M. DesimoneSearch for more papers by this author Tammy A. Davidson, Tammy A. DavidsonSearch for more papers by this authorJoseph M. Desimone, Joseph M. DesimoneSearch for more papers by this author Book Editor(s):Dr. Philip G. Jessop, Dr. Philip G. Jessop Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470, Mülheim an der Ruh, GermanySearch for more papers by this authorProf. Walter Leitner, Prof. Walter Leitner Department of Chemistry, University of California, Davis, California, 95616, USASearch for more papers by this author First published: 08 July 1999 https://doi.org/10.1002/9783527613687.ch15 AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Summary This chapter contains sections titled: Introduction Homogeneous Solution Polymerizations Heterogeneous Polymerizations Metal-catalyzed Polymerizations Step-growth Polymerizations Hybrid Systems Conclusions Acknowledgments Chemical Synthesis Using Supercritical Fluids RelatedInformation}, booktitle={Chemical Synthesis Using Supercritical Fluids}, publisher={J. Wiley-VCH}, author={Davidson, T. and DeSimone, J.M.}, editor={Jessop, P.G. and Leitner, W.Editors}, year={1999}, pages={297–325} } @article{kendall_canelas_young_desimone_1999, title={Polymerizations in Supercritical Carbon Dioxide}, volume={99}, ISSN={0009-2665 1520-6890}, url={http://dx.doi.org/10.1021/cr9700336}, DOI={10.1021/cr9700336}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolymerizations in Supercritical Carbon DioxideJonathan L. Kendall, Dorian A. Canelas, Jennifer L. Young, and Joseph M. DeSimoneView Author Information Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290 Cite this: Chem. Rev. 1999, 99, 2, 543–564Publication Date (Web):January 22, 1999Publication History Received30 June 1998Revised23 November 1998Published online22 January 1999Published inissue 1 February 1999https://pubs.acs.org/doi/10.1021/cr9700336https://doi.org/10.1021/cr9700336research-articleACS PublicationsCopyright © 1999 American Chemical SocietyRequest reuse permissionsArticle Views5192Altmetric-Citations758LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Monomers,Polymer particles,Polymerization,Polymers,Solvents Get e-Alerts}, number={2}, journal={Chemical Reviews}, publisher={American Chemical Society (ACS)}, author={Kendall, Jonathan L. and Canelas, Dorian A. and Young, Jennifer L. and DeSimone, Joseph M.}, year={1999}, month={Feb}, pages={543–564} } @article{shiho_desimone_1999, title={Preparation of micron-size polystyrene particles in supercritical carbon dioxide}, volume={37}, ISSN={0887-624X 1099-0518}, url={http://dx.doi.org/10.1002/(sici)1099-0518(19990715)37:14<2429::aid-pola17>3.0.co;2-b}, DOI={10.1002/(sici)1099-0518(19990715)37:14<2429::aid-pola17>3.0.co;2-b}, abstractNote={The dispersion polymerization of styrene in supercritical CO2 utilizing poly(1,1-dihydroperfluorooctyl acrylate) (p-FOA) as a polymeric stabilizer was investigated as well as poly(1,1-dihydroperfluorooctyl methacrylate) (p-FOMA). The resulting high yield (>85%) of spherical and relatively uniform polystyrene (PS) particles with micron-size range (2.9–9.6 µm) was formed for 40 h at 370 bar using various amounts of p-FOA and p-FOMA as a stabilizer with good stability until the end of the reaction. The particle diameter was shown to be dependent on the weight percent of added stabilizer. Previously, we reported that p-FOA was not effective for the dispersion polymerization of styrene as a stabilizer. Here, we find that p-FOA can indeed be an effective stabilizer for the dispersion polymerization of styrene in supercritical CO2, but the pressure necessary to achieve good stability is higher than pressure used by us previously. This study suggests the possibility that fluorinated acrylic homopolymers are effective for the dispersion polymerization of various kinds of monomers as a stabilizer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2429–2437, 1999}, number={14}, journal={Journal of Polymer Science Part A: Polymer Chemistry}, publisher={Wiley}, author={Shiho, Hiroshi and Desimone, Joseph M.}, year={1999}, month={Jul}, pages={2429–2437} } @article{betts_canelas_cochran_desimone_londono_mcclain_samulski_triolo_wignall_1999, title={Small Angle Neutron Scattering from Polymers in Supercritical Carbon Dioxide}, volume={10}, DOI={10.1080/10448639908233669}, abstractNote={Abstract Above its critical point, carbon dioxide forms a supercritical (SC) solvent which promises to be an environmentally responsible replacement for the organic solvents currently used in polymer synthesis and processing. CO2–soluble molecules (e.g. tluoropolymers) have been charkterized using small angle neutron scattering (SANS). By analogy with light and small-angle X–ray scattering (SAXS) experiments on polymers in dilute solution, the radius of gyration (Rg), molecular weight (MW) and second osmotic virial coefficient (A,) are determined from SANS experiments in SC–CO2. However, many polymers do not dissolve in this medium and in order to promote the synthesis of such materials, a range of amphiphilic block copolymers has been developed. These molecules function as surfactants or emulsifying agents to solubilize the CO2–phobic polymers. In the case of diblock copolymers in SC–CO2, aggregation occurs when the solvent is preferential for one of the blocks, and SANS allows the size and shape of the aggregates (micelles) to be determined. Illustrative examples of these studies are given and neutron scattering promises to give the same level of insight into polymers and amphiphiles in supercritical media that it has provided in the condensed state and in aqueous systems.}, number={2}, journal={Neutron News}, author={Betts, D.E. and Canelas, D.A. and Cochran, H.D. and DeSimone, J.M. and Londono, J.D. and McClain, J.B. and Samulski, E.T. and Triolo, R. and Wignall, G.D.}, year={1999}, pages={10–15} } @article{gross_flowers_roberts_kiserow_desimone_1999, title={Solid-State Polymerization of Polycarbonates Using Supercritical CO2}, volume={32}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma981395y}, DOI={10.1021/ma981395y}, abstractNote={We report the extension of the crystallization process with supercritical CO 2 to granules or beads of low molecular weight polycarbonate in an effort to create a material that can undergo slid-state polymerization without using toxic organic solvents}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Gross, Stephen M. and Flowers, Devin and Roberts, George and Kiserow, Douglas J. and DeSimone, Joseph M.}, year={1999}, month={May}, pages={3167–3169} } @misc{desimone_carbonell_1999, title={Spin coating method and apparatus for liquid carbon dioxide systems}, volume={6,001,418}, number={1999 Dec.14}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carbonell, R. G.}, year={1999}, month={Dec} } @article{henon_camaiti_burke_carbonell_desimone_piacenti_1999, title={Supercritical CO2 as a solvent for polymeric stone protective materials}, volume={15}, ISSN={["1872-8162"]}, DOI={10.1016/S0896-8446(99)00005-4}, abstractNote={The utilization of CO2 as a potential solvent for fluoropolymers used for the protection of civil infrastructures (buildings, bridges, monuments, etc.) is of major environmental as well as economic importance. The cloud points of six perfluoropolyethers at different weight concentrations in CO2 have been measured over a wide range of pressures. The results show that these fluorinated polymers are readily soluble in pure CO2 (no cosolvent or surfactant needed) at temperatures close to 30°C and pressures below 210 bars. The solubilities of the different polymeric products are strongly depend on the polymer hydrogen content and molecular weight.}, number={2}, journal={JOURNAL OF SUPERCRITICAL FLUIDS}, author={Henon, FE and Camaiti, M and Burke, ALC and Carbonell, RG and DeSimone, JM and Piacenti, F}, year={1999}, month={Jun}, pages={173–179} } @inproceedings{betts_johnson_leroux_desimone_1998, place={Washington, DC}, series={ACS Symposium Series}, booktitle={Controlled Radical Polymerization}, publisher={American Chemical Society}, author={Betts, D.E. and Johnson, T. and LeRoux, D. and DeSimone, J.M.}, editor={Matyjaszewski, K.Editor}, year={1998}, pages={418–432}, collection={ACS Symposium Series} } @inproceedings{hoggan_carbonell_desimone_cramer_stewart_1998, place={Flemington, NJ}, title={Detergent-Aided Cleaning of Metal Surfaces in Liquid Carbon Dioxide}, booktitle={CleanTech98 Proceedings}, publisher={Witter Publishing}, author={Hoggan, E.N. and Carbonell, R.G. and DeSimone, J.M. and Cramer, G.L. and Stewart, G.M.}, year={1998}, pages={137–146} } @article{cain_zhang_betts_desimone_johnson_1998, title={Diffusion of Block Copolymers in Liquid CO2:  Evidence of Self-Assembly from Pulsed Field Gradient NMR}, volume={120}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja981328j}, DOI={10.1021/ja981328j}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTDiffusion of Block Copolymers in Liquid CO2: Evidence of Self-Assembly from Pulsed Field Gradient NMRJudith B. Cain, Kewei Zhang, Douglas E. Betts, Joseph M. DeSimone, and Charles S. JohnsonView Author Information Department of Chemistry, University of North Carolina Chapel Hill, North Carolina 27599-3290 Cite this: J. Am. Chem. Soc. 1998, 120, 36, 9390–9391Publication Date (Web):August 29, 1998Publication History Received20 April 1998Revised3 August 1998Published online29 August 1998Published inissue 1 September 1998https://pubs.acs.org/doi/10.1021/ja981328jhttps://doi.org/10.1021/ja981328jrapid-communicationACS PublicationsCopyright © 1998 American Chemical SocietyRequest reuse permissionsArticle Views224Altmetric-Citations21LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Copolymers,Diffusion,Micelles,Polymers,Transport properties Get e-Alerts}, number={36}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Cain, Judith B. and Zhang, Kewei and Betts, Douglas E. and DeSimone, Joseph M. and Johnson, Charles S.}, year={1998}, month={Sep}, pages={9390–9391} } @article{dardin_desimone_samulski_1998, title={Fluorocarbons Dissolved in Supercritical Carbon Dioxide. NMR Evidence for Specific Solute−Solvent Interactions}, volume={102}, ISSN={1520-6106 1520-5207}, url={http://dx.doi.org/10.1021/jp972127p}, DOI={10.1021/jp972127p}, abstractNote={The proton and fluorine chemical shifts of n-hexane, perfluoro-n-hexane, and 1,1-dihydroperfluorooctylpropionate dissolved in supercritical carbon dioxide have been studied using high-pressure, high-resolution nuclear magnetic resonance. The CO2 density differentially influences 1H and 19F chemical shifts, which, in turn, suggest specific solute−solvent interactions between CO2 and fluorinated compounds. The density-dependent proton chemical shifts are exclusively governed by changes in the bulk susceptibility of CO2; these shifts exhibit only a slight temperature dependence. By contrast, the 19F signals show that an additional mechanisma van der Waals termcontributes to the magnetic shielding, and this has to be taken into account to explain the experimental shifts as a function of CO2 density and temperature. Furthermore, the 19F NMR data also show a distinct site specificity which is qualitatively explained in terms of the surface accessibility of fluorine atoms in the various CF2(CF3) units in fluoroc...}, number={10}, journal={The Journal of Physical Chemistry B}, publisher={American Chemical Society (ACS)}, author={Dardin, Alexander and DeSimone, Joseph M. and Samulski, Edward T.}, year={1998}, month={Mar}, pages={1775–1780} } @article{harrison_da rocha_yates_johnston_canelas_desimone_1998, title={Interfacial Activity of Polymeric Surfactants at the Polystyrene−Carbon Dioxide Interface}, volume={14}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la980323x}, DOI={10.1021/la980323x}, abstractNote={The reduction of the interfacial tension at the polystyrene (PS, Mn = 1850)−supercritical CO2 interface is reported for poly(1,1-dihydroperfluorooctyl acrylate) (PFOA) and the block copolymers PS-b-PFOA (3.7K/27K) and PS-b-poly(dimethylsiloxane) (PDMS) (2K/16K, 500/10K) at 45 °C. PS-b-PDMS (2K/16K) lowers the interfacial tension to 0.5 dyn/cm at 45 °C and 238 bar, more than that of any of the other copolymers. On the basis of the dynamics of the lowering of the interfacial tension, the apparent diffusion coefficient of PS-b-PDMS (2K/16K) is 8 × 10-6 cm2/s. The critical micelle concentration of PS-b-PFOA (3.7K/27K) is 9 × 10-4 wt %. Whereas both the PDMS- and PFOA-based copolymers studied adsorb on the PS surface, PS-b-PFOA is much more effective in stabilizing the PS emulsions. The difference in stabilization is discussed in terms of the surfactant adsorption and the interactions of the anchor and buoy blocks with CO2 and the PS surface.}, number={24}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Harrison, Kristi L. and da Rocha, Sandro R. P. and Yates, M. Z. and Johnston, Keith P. and Canelas, Dorian and DeSimone, Joseph M.}, year={1998}, month={Nov}, pages={6855–6863} } @article{buhler_dobrynin_desimone_rubinstein_1998, title={Light-Scattering Study of Diblock Copolymers in Supercritical Carbon Dioxide:  CO2Density-Induced Micellization Transition}, volume={31}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma980442j}, DOI={10.1021/ma980442j}, abstractNote={The behavior of polymeric surfactant polyvinyl acetate (PVAC)-b-poly(1,1,2,2-tetrahydroperfluorooctyl acrylate) (PTAN) in supercritical carbon dioxide (CO2) was investigated using static and dynamic light scattering. We observed three regions on the phase diagram of the copolymer in supercritical CO2:  (i) two-phase region at low CO2 density; (ii) solutions of spherical micelles at intermediate CO2 densities; (iii) solutions of unimers (individual copolymer chains) at high CO2 densities. The aggregation number (the number of copolymer chains in a micelle) decreases with an increasing density of supercritical CO2 in region (ii). An increase of the CO2 density corresponds to the improvement of solvent quality for both blocks of the copolymer (PVAC and PTAN). The hydrodynamic radius of micelles and unimers was measured using dynamic light scattering in regions (ii) and (iii), respectively. This light-scattering study is the first one reporting a solvent density-induced transition between spherical micelles a...}, number={21}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Buhler, E. and Dobrynin, A. V. and DeSimone, J. M. and Rubinstein, M.}, year={1998}, month={Oct}, pages={7347–7355} } @inbook{mistele_desimone_1998, place={Oxford, England}, title={Metal catalysis and processing utilizing carbon dioxide}, ISBN={9780198501701}, booktitle={Green Chemistry: Frontiers in Benign Chemical Synthesis and Processing}, publisher={Oxford University Press}, author={Mistele, C. and DeSimone, J.M.}, editor={Anastas, Paul T. and Williamson, Tracy C.Editors}, year={1998}, pages={286–312} } @article{luna-bárcenas_mawson_takishima_desimone_sanchez_johnston_1998, title={Phase behavior of poly(1,1-dihydroperfluorooctylacrylate) in supercritical carbon dioxide}, volume={146}, ISSN={0378-3812}, url={http://dx.doi.org/10.1016/s0378-3812(98)00215-5}, DOI={10.1016/s0378-3812(98)00215-5}, abstractNote={Liquid–fluid phase equilibria data are reported for the poly(1,1-dihydroperfluorooctylacrylate) (poly(FOA))–CO2 system at sub- and supercritical fluid conditions and modeled with the statistical associated fluid theory (SAFT). Lower critical solution temperature (LCST) phase behavior is observed with a critical concentration between 1.0 and 2.0 wt.% poly(FOA). The high solubility of poly(FOA) is consistent with its low cohesive energy density and the weak van der Waals forces of CO2. To aid this analysis, pressure–volume–temperature (PVT) data are reported for pure poly(FOA) and correlated with lattice-fluid and SAFT theory.}, number={1-2}, journal={Fluid Phase Equilibria}, publisher={Elsevier BV}, author={Luna-Bárcenas, Gabriel and Mawson, Simon and Takishima, Shigeki and DeSimone, Joseph M and Sanchez, Isaac C and Johnston, Keith P}, year={1998}, month={May}, pages={325–337} } @article{canelas_betts_desimone_yates_johnston_1998, title={Poly(vinyl acetate) and poly(vinyl acetate-co-ethylene) latexes via dispersion polymerizations in carbon dioxide}, volume={31}, ISSN={["1520-5835"]}, DOI={10.1021/ma980596z}, abstractNote={The preparation of stable dispersions of poly(vinyl acetate) or ethylene/vinyl acetate copolymers via dispersion polymerizations in a carbon dioxide continuous phase has been investigated. The effectiveness of stabilizers of various chemical compositions and architectures was compared. Both fluorinated and siloxane-based stabilizers including homopolymers, block copolymers, and reactive macromonomers were employed. Effects of variations in the reaction temperature, pressure, stabilizer composition, stabilizer concentration, and use of cosolvents on the resulting product were investigated. A turbidimetry technique was used successfully to monitor dispersed-phase volume fractions, particle sizes, and number densities during the polymerizations and to give the final particle sizes at the end of the polymerizations. The fluorinated stabilizers gave rise to smaller particles and more stable latexes when compared to the siloxane-based stabilizers.}, number={20}, journal={MACROMOLECULES}, author={Canelas, DA and Betts, DE and DeSimone, JM and Yates, MZ and Johnston, KP}, year={1998}, month={Oct}, pages={6794–6805} } @article{canelas_de simone_1998, title={Polymer shake up}, volume={34}, number={8}, journal={Chemistry in Britain}, author={Canelas, D. and De Simone, J.}, year={1998}, pages={38–40} } @article{quadir_desimone_van herk_german_1998, title={Pulsed-Laser Polymerization of Methyl Methacrylate in Liquid and Supercritical Carbon Dioxide}, volume={31}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma980658l}, DOI={10.1021/ma980658l}, abstractNote={The free-radical propagation rate coefficients for methyl methacrylate (MMA) in liquid and supercritical carbon dioxide have been successfully determined using pulsed-laser polymerization (PLP) method. The effect of carbon dioxide solvency on the propagation rate coefficient, kp, is examined at 180 bar for a temperature range of 20−80 °C. The temperature dependency of the obtained kp data is evaluated by use of the Arrhenius equation. The resulting activation energy is (25.4 ± 1.2 kJ·mol-1, and the preexponential factor is (5.2 ± 3.0 × 106 L·mol-1·s-1. These results are compared to the bulk activation parameters for the propagation rate coefficient of MMA as set forth by the IUPAC working party on “Modeling of Kinetics and Processes of Polymerization”. The discrepancy in the propagation rate coefficients at the lower temperature regime is attributed to a solvent effect of CO2. This is consistent with the results from a recent PLP study of this monomer.}, number={19}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Quadir, Murat A. and DeSimone, Joseph M. and van Herk, Alex M. and German, Anton L.}, year={1998}, month={Sep}, pages={6481–6485} } @article{hamilton_rooney_desimone_mistele_1998, title={Stereochemistry of Ring-Opened Metathesis Polymers Prepared in Liquid CO2at High Pressure Using Ru(H2O)6(Tos)2as Catalyst}, volume={31}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9715536}, DOI={10.1021/ma9715536}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTStereochemistry of Ring-Opened Metathesis Polymers Prepared in Liquid CO2 at High Pressure Using Ru(H2O)6(Tos)2 as CatalystJ. G. Hamilton, J. J. Rooney, J. M. DeSimone, and C. MisteleView Author Information School of Chemistry, The Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland, and Department of Chemistry, CB#3290, Venable and Kenan Laboratories, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290 Cite this: Macromolecules 1998, 31, 13, 4387–4389Publication Date (Web):June 9, 1998Publication History Received22 October 1997Revised16 April 1998Published online9 June 1998Published inissue 1 June 1998https://pubs.acs.org/doi/10.1021/ma9715536https://doi.org/10.1021/ma9715536rapid-communicationACS PublicationsCopyright © 1998 American Chemical SocietyRequest reuse permissionsArticle Views180Altmetric-Citations32LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Alcohols,Catalysts,Ligands,Metathesis polymerization,Polymers Get e-Alerts}, number={13}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Hamilton, J. G. and Rooney, J. J. and DeSimone, J. M. and Mistele, C.}, year={1998}, month={Jun}, pages={4387–4389} } @article{jaimes_arcana_brethon_mathieu_schue_desimone_1998, title={Structure and Morphology of Poly([R,S]-beta-butyrolactone) Synthesized from Aluminoxane Catalysts}, volume={34}, DOI={10.1016/S0014-3057(97)00106-7}, number={2}, journal={European Polymer Journal}, author={Jaimes, C. and Arcana, M. and Brethon, A. and Mathieu, A. and Schue, F. and DeSimone, J.M.}, year={1998}, pages={175–185} } @article{gross_givens_jikei_royer_khan_desimone_odell_hamer_1998, title={Synthesis and Swelling of Poly(bisphenol A carbonate) Using Supercritical CO2}, volume={31}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma980234r}, DOI={10.1021/ma980234r}, abstractNote={Introduction. Among the advantages of traditional melt-phase polymerization processes is the potential to produce a high molecular weight polymer without the use of solvent. While solvent-free melt-phase polymerization methods avoid the use of environmentally detrimental solvent mixtures, it would be convenient to mediate the high viscosity of the polymer melt associated with the attainment of high molecular weight polymer, especially near the end of the polymerization. It has been noted previously that the condensate associated with certain step-growth polymerizations can be removed more effectively by swelling or plasticizing the polymer melt in some manner, thus increasing both chain mobility and free volume in the melt phase.1 Swelling agents should improve polymerization rates of step-growth polymerization processes by increasing the surface area available for condensate removal, but such a technique is not an advantage from a processing standpoint if it introduces to the reaction a swelling agent that is toxic, costly, or difficult to separate from the end product. Since many step-growth polymers are used for food and beverage packaging applications, absolute safety of any additive to the melt phase is imperative. Polycarbonates are an important class of polymers due primarily to their toughness and optical clarity. Two different, industrially suitable, synthetic routes were developed virtually simultaneously by Bayer A.G. and General Electric Co.2 The first route involves an interfacial reaction between 4,4′-isopropylidene bisphenol (bisphenol A) and phosgene using a biphasic system of methylene chloride and an alkaline aqueous phase with a phase-transfer catalyst. The other route involves a melt transesterification between a bisphenol and a diaryl carbonate, typically diphenyl carbonate. The former has become the predominant industrial route despite the drawbacks of the use of both phosgene and methylene chloride. The difference in pKa of various bisphenols, their partitioning between the two phases, and interaction with the phase-transfer catalyst reduce the utility of this route for producing a wide range of statistical copolymers.3 For this reason, as well as both the ease of synthesis of the monomer and satisfactory properties of the derived polymer, the industry has centered on the use of bisphenol A. Melt transesterification provides a useful route to a wide range of statistical copolymers, but the high viscosity of the melt limits the molecular weight that can practically be achieved. The high viscosity, which, for example, can reach 106 P for poly(4,4′-cyclohexylidene bisphenol) carbonate at the reaction/processing temperature of 280 °C, is the result of the polymer chain stiffness which also provides the desirable mechanical properties. Such viscosities necessitate the use of high temperatures, which, in turn, can lead to discoloration in the final product. Although CO2 is a nonsolvent for most polymers (exceptions include many fluoropolymers and silicones), CO2 has been found to be an excellent plasticizing agent.4-7 Thus, if the mechanism of a given polymerization process is compatible with CO2, many mass/bulk polymerization processes could benefit from the plasticization afforded by CO2. Recent work using liquid or supercritical carbon dioxide as a solvent medium has shown that supercritical CO2 is compatible with a number of polymerization types, including free radical,8 cationic,9 ring opening,10 and oxidative coupling.11 A number of small molecules display significant solubility in liquid or supercritical CO2, including a number of step-growth reaction byproducts. Although water has a low solubility in supercritical CO2, other common condensates, such as acetic acid, neopentyl glycol, and phenol, have the potential to be extracted from a reaction melt using supercritical fluid extraction methods that would drive the reaction to completion. Conventional methods of melt-phase step-growth polymerizations use vacuum techniques to remove condensates, but extraction of condensates using a SCFE method with CO2 has the added benefit of introducing a swelling agent into the polymer melt. In addition, the commercial scale use of vacuum methods requires tedious process controls and extensive capital investment in order to maintain vacuum integrity for extended periods of time (years) with little maintenance. The use of low-pressure CO2 as a continuous phase for bulk-phase polymerizations of polyesters and polyamides has been proposed,12 but the issue of the potential plasticization of the melt phase afforded by high-pressure CO2 has only been recently demonstrated.13 We are currently investigating the effects of CO2 as the swelling medium for melt-phase step-growth polymerizations. If the mechanism of polymerization is compatible with CO2, we anticipate that the swelling of the polymer melt by supercritical CO2 will lead to a reduction in the melt viscosity, which, in turn, may lead to increased reaction rates and increased production quality (color, higher purity lower residual monomer, etc.). Polymer Swelling Measurements. Measurements of polymer swelling with CO2 was performed in a specially designed high-pressure view cell, constructed of 316 stainless steel. The window of the cell consists of a steel plug in series with a brass O-ring, a 1 in. o.d., 0.5 in. thick sapphire window and a 0.002 in. thick Teflon gasket. High-pressure CO2 was introduced to the cell using a syringe pump (Isco 260D). A digital camera (Pulnix TM-7CN) outfitted with a 50 mm lens (Nikon f/1.4D) was used to view and record the swelling kinetics * To whom correspondence should be addressed. † University of North Carolina at Chapel Hill. ‡ North Carolina State University. § Presently at MiCell Technologies. ⊥ Presently at the Tokyo Institute of Technology. 9090 Macromolecules 1998, 31, 9090-9092}, number={25}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Gross, Stephen M. and Givens, Ramone D. and Jikei, Mitsutoshi and Royer, Joseph R. and Khan, Saad and DeSimone, Joseph M. and Odell, Peter G. and Hamer, Gordon K.}, year={1998}, month={Dec}, pages={9090–9092} } @misc{gross_givens_jikei_royer_khan_desimone_odell_hamer_1998, title={Synthesis and swelling of poly(bisphenol A carbonate) using supercritical CO2}, volume={31}, number={25}, journal={Macromolecules}, author={Gross, S. M. and Givens, R. D. and Jikei, M. and Royer, J. R. and Khan, S. and Desimone, J. M. and Odell, P. G. and Hamer, G. R.}, year={1998}, month={Dec}, pages={9090–9092} } @article{kassis_desimone_linton_remsen_lange_friedman_1997, title={A Direct Deposition Method for Coupling Matrix-assisted Laser Desorption/Ionization Mass Spectrometry with Gel Permeation Chromatography for Polymer Characterization}, volume={11}, ISSN={0951-4198 1097-0231}, url={http://dx.doi.org/10.1002/(sici)1097-0231(19970630)11:10<1134::aid-rcm910>3.0.co;2-0}, DOI={10.1002/(sici)1097-0231(19970630)11:10<1134::aid-rcm910>3.0.co;2-0}, abstractNote={Matrix-assisted laser desorption/ionization (MALDI) measurements of polymeric materials of narrow polydispersity provide molecular weight measurements that agree closely with those from conventional tools such as gel-permeation chromatography (GPC). However, materials that have a broader molecular weight distribution (polydispersity) > 1.1) have been shown to diminish the accuracy of the MALDI results. In a recent effort to overcome this limitation, some researchers have utilized GPC prior to MALDI analysis to collect fractions with narrower molecular weight distributions. In our research, the GPC eluent was spray deposited onto a rotating matrix-coated substrate and the resulting polymer ‘trail’ was characterized directly by MALDI. Specifically, molecular weight information was determined using various points along poly(methyl methacrylate) sample ‘trails’ deposited on a matrix of trans-3-indoleacrylic acid. The overall number-average molecular weight (M n) and molecular weight distribution (MWD) for each of the samples were calculated. The Mn values are in fairly good agreement with manufacturer's values, though the MWD values determined by MALDI are narrower. © 1997 John Wiley & Sons, Ltd.}, number={10}, journal={Rapid Communications in Mass Spectrometry}, publisher={Wiley}, author={Kassis, Camille E. and DeSimone, Joseph M. and Linton, Richard W. and Remsen, Edward E. and Lange, Gary W. and Friedman, Robert M.}, year={1997}, month={Jun}, pages={1134–1138} } @article{kassis_desimone_linton_lange_friedman_1997, title={An Investigation into the Importance of Polymer-Matrix Miscibility Using Surfactant Modified Matrix-assisted Laser Desorption/Ionization Mass Spectrometry}, volume={11}, ISSN={0951-4198 1097-0231}, url={http://dx.doi.org/10.1002/(sici)1097-0231(19970830)11:13<1462::aid-rcm44>3.0.co;2-2}, DOI={10.1002/(sici)1097-0231(19970830)11:13<1462::aid-rcm44>3.0.co;2-2}, abstractNote={Sample preparation, namely finding a suitable matrix–analyte combination, has been one of the most important concerns in using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for synthetic polymers. Herein we report the novel use of surfactants in the polymer sample preparation procedure. Specifically, three nonionic surfactants were investigated for MALDI analysis of poly(methyl methacrylate) (PMMA). This approach resulted in major enhancements in the PMMA molecular ion signals with dithranol as the matrix. The results illustrate the importance of polymer–matrix miscibility in optimizing MALDI investigations. © 1997 John Wiley & Sons, Ltd.}, number={13}, journal={Rapid Communications in Mass Spectrometry}, publisher={Wiley}, author={Kassis, Camille M. and DeSimone, Joseph M. and Linton, Richard W. and Lange, Gary W. and Friedman, Robert M.}, year={1997}, month={Aug}, pages={1462–1466} } @article{canelas_burke_desimone_1997, title={Carbon Dioxide as a Continuous Phase for Polymer Synthesis}, volume={53}, number={12}, journal={Plastics Engineering}, author={Canelas, D.A. and Burke, A. and DeSimone, J.M.}, year={1997}, pages={37–40} } @article{clark_kendall_desimone_1997, title={Cationic Dispersion Polymerizations in Liquid Carbon Dioxide}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9619344}, DOI={10.1021/ma9619344}, abstractNote={The successful cationic dispersion polymerization of styrene in liquid carbon dioxide using amphiphilic block copolymers is reported. Vinyl ether block copolymers consisting of a CO2-philic fluorinated segment and a poly(methyl vinyl ether) anchoring segment were employed to stabilize the growing polystyrene (PS) particles. The effect of stabilization in these polymerizations on molar mass, molar mass distribution, and polymer yield was studied as a function of temperature and surfactant composition. Scanning electron microscopy confirmed the formation of PS particles ranging in size from 300 nm to 1 μm in diameter.}, number={20}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Clark, M. R. and Kendall, J. L. and DeSimone, J. M.}, year={1997}, month={Oct}, pages={6011–6014} } @article{canelas_desimone_1997, title={Dispersion Polymerizations of Styrene in Carbon Dioxide Stabilized with Poly(styrene-b-dimethylsiloxane)}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma970579u}, DOI={10.1021/ma970579u}, abstractNote={Herein we report the use of poly(styrene-b-dimethylsiloxane) block copolymers as steric stabilizers for dispersion polymerizations of styrene in a carbon dioxide continuous phase. It was demonstrated that the anchor-soluble balance (ASB) of the stabilizer has a dramatic effect on both the progress of the reaction and the morphology of the resulting polystyrene (PS) colloid. When a stabilizer with an appropriate ASB is employed, the initial concentrations of styrene, stabilizer, and helium have substantial effects on the resulting size and dispersity of the colloidal particles. Dispersion polymerizations carried out under a series of different pressures (143−439 bar) resulted in variations in the conversion, molecular weight, and PS particle diameter, suggesting that the reaction is extremely sensitive to the density of the continuous phase. An investigation of the progress of the reaction as a function of time at two different temperatures revealed that the average molecular weight increases gradually ove...}, number={19}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Canelas, Dorian A. and DeSimone, Joseph M.}, year={1997}, month={Sep}, pages={5673–5682} } @article{hsiao_desimone_1997, title={Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide: Influence of helium concentration on particle size and particle size distribution}, volume={35}, ISSN={0887-624X 1099-0518}, url={http://dx.doi.org/10.1002/(sici)1099-0518(19970730)35:10<2009::aid-pola16>3.0.co;2-k}, DOI={10.1002/(sici)1099-0518(19970730)35:10<2009::aid-pola16>3.0.co;2-k}, abstractNote={Dispersion polymerizations of methyl methacrylate utilizing poly(1,1,-dihydroperfluorooctyl acrylate) as a steric stabilizer in supercritical carbon dioxide (CO2) were carried out in the presence of helium. Particle size and particle size distribution were found to be dependent on the amount of inert helium present. Particle sizes ranging from 1.64 to 2.66 μm were obtained with various amounts of helium. Solvatochromic investigations using 9-(α-perfluoroheptyl-β,β-dicyanovinyl)julolidine indicated that the solvent strength of CO2 decreases with increasing helium concentration. This effect was confirmed by calculations of Hildebrand solubility parameters. Dispersion polymerization results indicate that PMMA particle size can be attenuated by the amount of helium present in supercritical CO2. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2009–2013, 1997}, number={10}, journal={Journal of Polymer Science Part A: Polymer Chemistry}, publisher={Wiley}, author={Hsiao, Yu-Ling and Desimone, Joseph M.}, year={1997}, month={Jul}, pages={2009–2013} } @article{quadir_snook_gilbert_desimone_1997, title={Emulsion Polymerization in a Hybrid Carbon Dioxide/Aqueous Medium}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma970259a}, DOI={10.1021/ma970259a}, abstractNote={The development of a new reaction medium is reported, based on a biphasic mixture of carbon dioxide and water for emulsion polymerizations:  a surfactant-free aqueous emulsion polymerization of methyl methacrylate using potassium persulfate under a varying head pressure of CO2 (0−350 bar) at 75 °C. The resulting polymer is a stable latex with particles of submicron size. The effect of CO2 on polymerization is relatively small, until there is a significant change at high CO2 pressure. This is seen by examining the molecular weight distribution in the form of the log(number distribution), P(M) (readily obtained by GPC). At pressures of 140 bar and below, the P(M) show the form expected for chain-stopping events dominated by transfer and by diffusion-controlled termination. At 280 bar, ln P(M) is significantly steeper than its lower-pressure counterpart at relatively low conversion (45%). This is attributed to swelling by supercritical CO2 reducing the viscosity of the particles, allowing more rapid termination.}, number={20}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Quadir, Murat A. and Snook, Rodd and Gilbert, Robert G. and DeSimone, Joseph M.}, year={1997}, month={Oct}, pages={6015–6023} } @article{o'neill_yates_harrison_johnston_canelas_betts_desimone_wilkinson_1997, title={Emulsion Stabilization and Flocculation in CO2. 1. Turbidimetry and Tensiometry}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9616930}, DOI={10.1021/ma9616930}, abstractNote={The stabilization and flocculation of emulsions of poly(2-ethylhexyl acrylate) (PEHA) in liquid and supercritical carbon dioxide (SC-CO2) with the homopolymer poly(1,1-dihydroperfluorooctyl acrylate) (PFOA), the diblock copolymer polystyrene-b-PFOA, and the triblock copolymer PFOA-b-poly(vinyl acetate)-b-PFOA were quantified by turbidimetry and measurements of interfacial tension. Upon decreasing the CO2 density, a distinct change in emulsion stability occurs at the critical flocculation density (CFD). Steric stabilization by the homopolymer PFOA is due to a small number of adsorbed segments and a large number of segments in loops and tails as determined by measurements of the PEHA−CO2 interfacial tension. Below the CFD, flocculation is irreversible due to bridging by the high molecular weight PFOA chains. PS-b-PFOA adsorbs much more strongly to the PEHA−CO2 interface than the other two stabilizers. Consequently, it provides the greatest resistance to emulsion flocculation, both above and below the CFD, a...}, number={17}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={O'Neill, M. L. and Yates, M. Z. and Harrison, K. L. and Johnston, K. P. and Canelas, D. A. and Betts, D. E. and DeSimone, J. M. and Wilkinson, S. P.}, year={1997}, month={Aug}, pages={5050–5059} } @article{yates_o'neil_johnston_webber_canelas_betts_desimone_1997, title={Emulsion Stabilization and Flocculation in CO2. 2. Dynamic Light Scattering}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma961694s}, DOI={10.1021/ma961694s}, abstractNote={Dynamic light scattering (DLS) was used to investigate steric stabilization and flocculation of dilute poly(2-ethylhexyl acrylate) (PEHA, Mw = 92K) emulsions in liquid CO2 at 25 °C by monitoring changes in droplet size over time at various CO2 densities. Two steric stabilizers were investigated:  a homopolymer, poly(1,1-dihydroperfluorooctyl acrylate) (PFOA, Mw = 1 × 106), and a block copolymer, polystyrene (Mn = 4.5K g/mol)-b-PFOA (Mn = 25K). For a concentration of 0.03 wt %, aggregates of PS-b-PFOA were observed in CO2 with an average hydrodynamic diameter of approximately 80 nm and a polydispersity index of 0.2−0.3 from the method of cumulants. Critical flocculation densities (CFDs) of PEHA emulsions were determined by lowering the CO2 density at constant temperature to induce flocculation. The CFDs of the emulsions agree closely with the ϑ point density of PFOA in CO2 for both the homopolymer and block copolymer stabilizers. Above the CFD, the emulsions have an average droplet size of 400−600 nm and a...}, number={17}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Yates, M. Z. and O'Neil, M. L. and Johnston, K. P. and Webber, S. and Canelas, D.A. and Betts, D.E. and DeSimone, J.M.}, year={1997}, month={Aug}, pages={5060–5067} } @article{cooper_londono_wignall_mcclain_samulski_lin_dobrynin_rubinstein_burke_fréchet_et al._1997, title={Extraction of a hydrophilic compound from water into liquid CO2 using dendritic surfactants}, volume={389}, ISSN={0028-0836 1476-4687}, url={http://dx.doi.org/10.1038/38706}, DOI={10.1038/38706}, number={6649}, journal={Nature}, publisher={Springer Nature}, author={Cooper, A. I. and Londono, J. D. and Wignall, G. and McClain, J. B. and Samulski, E. T. and Lin, J. S. and Dobrynin, A. and Rubinstein, M. and Burke, A. L. C. and Fréchet, J. M. J. and et al.}, year={1997}, month={Sep}, pages={368–371} } @article{dukes_harbron_forbes_desimone_1997, title={Flow system and 9.5 GHz microwave resonators for time-resolved and steady-state electron paramagnetic resonance spectroscopy in compressed and supercritical fluids}, volume={68}, ISSN={0034-6748 1089-7623}, url={http://dx.doi.org/10.1063/1.1148149}, DOI={10.1063/1.1148149}, abstractNote={An apparatus for the electron paramagnetic resonance (EPR) detection of stable and transient free radicals in pressurized liquids and supercritical fluids is described. The construction of a quartz EPR sample cell capable of withstanding pressures up to 3000 psi (204 atm) and the components of a high pressure flow system are explained and illustrated. In order to accommodate the thick-walled, high pressure sample tube, two X-band (9.5 GHz) microwave cavities were fabricated. One is a brass, cylindrical TE011 cavity for time-resolved (direct detection) EPR experiments where field modulation was not necessary, and the other is a silver wire-wound cylindrical TE011 cavity, mounted in a quartz support tube. The wire-wound cavity allows for simultaneous light excitation and field modulation for steady-state EPR. Both cavities are fitted with tunable end plates to facilitate tuning at X band in the face of large frequency shifts when the sample tube is introduced to the resonator and to allow for operation with smaller sample tubes at ambient pressure. Microwave coupling, flow optimization, and UV-light access for both cavities are described, and sample spectra in both time-resolved and steady-state modes are reported.}, number={6}, journal={Review of Scientific Instruments}, publisher={AIP Publishing}, author={Dukes, Katerina E. and Harbron, Elizabeth J. and Forbes, Malcolm D. E. and DeSimone, Joseph M.}, year={1997}, month={Jun}, pages={2505–2510} } @article{dardin_cain_desimone_johnson_samulski_1997, title={High-Pressure NMR of Polymers Dissolved in Supercritical Carbon Dioxide}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma961917e}, DOI={10.1021/ma961917e}, abstractNote={High-pressure, high-resolution proton nuclear magnetic resonance spectroscopy has been utilized to study the solution behavior of poly(1,1-dihydroperfluorooctyl acrylate) (PFOA) and poly(1,1-dihydr...}, number={12}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Dardin, Alexander and Cain, J. B. and DeSimone, J. M. and Johnson, C. S. and Samulski, E. T.}, year={1997}, month={Jun}, pages={3593–3599} } @article{mas_jaaba_schue_belu_kassis_linton_desimone_1997, title={Modification de Surface de Poly (Hydroxybutyrate-co-9% Hydroxyvalerate) Par Polymerisation Par Plasma d'Alcool Allylique}, volume={33}, ISSN={0014-3057}, url={http://dx.doi.org/10.1016/s0014-3057(96)00154-1}, DOI={10.1016/s0014-3057(96)00154-1}, abstractNote={La polymérisation par plasma d'alcool allylique conduit au dépôt d'un film minceà la surface de P(HB-co-9% HV). L'enrichissement en oxygène est faible mais se traduit par une augmentation des carbones de types CO, C-OC, C-OH déterminée par ESCA et une mouillabilité supérieure par rapport au matériau non traité. La mouillabilité diminue avec l'augmentation de la température et du temps de stockage après traitement puis se stabilise mais elle reste fixeà −20°C. L'interprétation est basée sur la réorientation des groupes polaires en surface et l'existence d'un dépôt non réticulé dont la valeur de la température de transition vitreuse serait comprise entre −20 et 25°C.) Allyl alcohol plasma polymerization permits to obtain a thin deposited film on to P(HB-co-9% HV) surface. The oxygen atomic increase is weak but gives an increase of Cls in CO, C-OC, C-OH bonds which is determinate by XPS analysis and a wettability greater than that of the non-treated material. The wettability decreases with storage temperature and time after treatment then it is stable. However it remains constant at − 20°C. The interpretation is supported by polar groups motions on the surface and the formation of a non-crosslinked deposited film whose the glass temperature value would be situated between −20 and 25°C. © 1997 Elsevier Science Ltd. All rights reserved}, number={3}, journal={European Polymer Journal}, publisher={Elsevier BV}, author={Mas, A. and Jaaba, H. and Schue, F. and Belu, A.M. and Kassis, C.M. and Linton, R.W. and Desimone, J.M.}, year={1997}, month={Mar}, pages={331–337} } @article{tanner_brookhart_desimone_1997, title={Observation of an Inverse Kinetic Isotope Effect in a Co(III)-Catalyzed Polymerization of Ethylene}, volume={119}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja971300s}, DOI={10.1021/ja971300s}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunicationObservation of an Inverse Kinetic Isotope Effect in a Co(III)-Catalyzed Polymerization of EthyleneMartha J. Tanner, M. Brookhart, and J. M. DeSimoneView Author Information Department of Chemistry University of North Carolina at Chapel Hill Chapel Hill, North Carolina 27514 Cite this: J. Am. Chem. Soc. 1997, 119, 32, 7617–7618Publication Date (Web):August 13, 1997Publication History Received24 April 1997Published online13 August 1997Published inissue 1 August 1997https://pubs.acs.org/doi/10.1021/ja971300shttps://doi.org/10.1021/ja971300srapid-communicationACS PublicationsCopyright © 1997 American Chemical SocietyRequest reuse permissionsArticle Views653Altmetric-Citations44LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Alkyls,Isotope effects,Metals,Monomers,Transition states Get e-Alerts}, number={32}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Tanner, Martha J. and Brookhart, M. and DeSimone, J. M.}, year={1997}, month={Aug}, pages={7617–7618} } @article{li_desimone_poon_samulski_1997, title={Photoinduced graft polymerization of styrene onto polypropylene substrates}, volume={64}, ISSN={0021-8995 1097-4628}, url={http://dx.doi.org/10.1002/(sici)1097-4628(19970502)64:5<883::aid-app8>3.0.co;2-l}, DOI={10.1002/(sici)1097-4628(19970502)64:5<883::aid-app8>3.0.co;2-l}, abstractNote={The photochemical grafting of styrene onto polypropylene (PP) using benzophenone (BP) and benzoin ethyl ether (BEE) as photosensitizers is described. The effects of various parameters (such as monomer and photosensitizer concentration, reaction time, and solvent) on percent grafting were studied. We found that BP is a very efficient photosensitizer for the grafting of styrene onto PP surfaces. Unlike BEE, BP does not initiate nongrafting homopolymerization reactions in solution which compete with grafting reactions. This is advantageous over other photosensitizers since homopolymer formed in solution can interfere with the grafting reaction as well complicate sample preparation and purification. The graft copolymers obtained using both BP and BEE were characterized by high resolution 1H-NMR, optical microscopy and swelling studies. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 883–889, 1997}, number={5}, journal={Journal of Applied Polymer Science}, publisher={Wiley}, author={Li, Yuhua and Desimone, Joseph M. and Poon, Chi-Duen and Samulski, Edward T.}, year={1997}, month={May}, pages={883–889} } @article{mas_jaaba_schue_belu_kassis_linton_desimone_1997, title={Poly(Hydroxybutyrate-co-9% Hydroxyvalerate) Film Surface Modification by Ar, O2, H2,O/O2, H2O, and H2O2 Plasma Treatment}, volume={34}, ISSN={1060-1325 1520-5738}, url={http://dx.doi.org/10.1080/10601329708014935}, DOI={10.1080/10601329708014935}, abstractNote={Abstract We modified poly(hydroxybutyrate-co-9% hydroxyvalerate) film surfaces with Ar, O2, H2O/O2, H2O, and H2O2 vapor plasma treatments. We measured the grafted oxygen concentration by XPS analyses and the wettability by a θH2O contact angle method. Comparison between these various plasma treatments seems to indicate a better surface wettability correlated to C-OH bonds obtained with H2O and H2O2 plasma than with Ar and O2 plasma which incorporate oxygen atoms in C˭O bonds more easily.}, number={1}, journal={Journal of Macromolecular Science, Part A}, publisher={Informa UK Limited}, author={Mas, A. and Jaaba, H. and Schue, F. and Belu, A. M. and Kassis, C. and Linton, R. W. and Desimone, J. M.}, year={1997}, month={Jan}, pages={67–79} } @article{van herk_manders_canelas_quadir_desimone_1997, title={Propagation Rate Coefficients of Styrene and Methyl Methacrylate in Supercritical CO2}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9703416}, DOI={10.1021/ma9703416}, abstractNote={• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.}, number={16}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={van Herk, Alex M. and Manders, Bart G. and Canelas, Dorian A. and Quadir, Murat A. and DeSimone, Joseph M.}, year={1997}, month={Aug}, pages={4780–4782} } @article{mawson_johnston_betts_mcclain_desimone_1997, title={Stabilized Polymer Microparticles by Precipitation with a Compressed Fluid Antisolvent. 1. Poly(fluoro acrylates)}, volume={30}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma961048t}, DOI={10.1021/ma961048t}, abstractNote={Poly(1,1-dihydroperfluorooctyl acrylate) (poly(FOA)) based stabilizers greatly reduce, and in some cases eliminate, flocculation of amorphous poly(methyl methacrylate) (PMMA) and polystyrene (PS) microparticles formed by precipitation into liquid CO2 at 23 °C. The microparticle stabilization mechanism is explained in terms of the stabilizer−CO2 phase behavior, the spray characteristics, and the interfacial activity of the stabilizer. Compared with the homopolymer poly(FOA), the diblock copolymer PS-b-poly(FOA) produces smaller and more spherical primary particles (0.1−0.3 μm) and also prevents flocculation at lower stabilizer concentrations. These differences are due to the greater interfacial activity of PS-b-poly(FOA). Steric stabilization commences in the jet on the order of several tenths of milliseconds and continues for seconds throughout the precipitator. With the use of a coaxial nozzle, precipitation is delayed and the stabilizers become even more effective at preventing flocculation.}, number={1}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Mawson, Simon and Johnston, Keith P. and Betts, Doug E. and McClain, Jim B. and DeSimone, Joseph M.}, year={1997}, month={Jan}, pages={71–77} } @article{londono_dharmapurikar_cochran_wignall_mcclain_betts_canelas_desimone_samulski_chillura-martino_et al._1997, title={The Morphology of Block Copolymer Micelles in Supercritical Carbon Dioxide by Small-Angle Neutron and X-ray Scattering}, volume={30}, ISSN={0021-8898}, url={http://dx.doi.org/10.1107/s0021889897002446}, DOI={10.1107/s0021889897002446}, abstractNote={Above its critical point, carbon dioxide forms a super-critical fluid, which promises to be an environmentally responsible replacement for the organic solvents traditionally used in polymerizations. Many lipophilic polymers such as polystyrene (PS) are insoluble in CO2, though polymerizations may be accomplished via the use of PS-fluoropolymer stabilizers, which act as emulsifying agents. Small-angle neutron and X-ray scattering have been used to show that these molecules form micelles with a CO2-phobic PS core and a CO2-philic fluoropolymer corona. When the PS block was fixed in length and the fluorinated corona block was varied, the number of block copolymer molecules per micelle (six to seven) remained constant. Thus, the coronal block molecular weight exerts negligible influence on the aggregation number, in accordance with the theoretical predictions of Halperin, Tirrell & Lodge [Adv. Polym. Sci. (1992), 100, 31–46]. These observations are relevant to understanding the mechanisms of micellization and solubilization in supercritical fluids.}, number={5}, journal={Journal of Applied Crystallography}, publisher={International Union of Crystallography (IUCr)}, author={Londono, J. D. and Dharmapurikar, R. and Cochran, H. D. and Wignall, G. D. and McClain, J. B. and Betts, D. E. and Canelas, D. A. and DeSimone, J. M. and Samulski, E. T. and Chillura-Martino, D. and et al.}, year={1997}, month={Oct}, pages={690–695} } @article{avdievich_dukes_forbes_desimone_1997, title={Time-Resolved EPR Study of a 1,9-Flexible Biradical Dissolved in Liquid Carbon Dioxide. Observation of a New Spin-Relaxation Phenomenon:  Alternating Intensities in Spin-Correlated Radical Pair Spectra}, volume={101}, ISSN={1089-5639 1520-5215}, url={http://dx.doi.org/10.1021/jp961947j}, DOI={10.1021/jp961947j}, abstractNote={X-band (9.5 GHz) time-resolved electron paramagnetic resonance (TREPR) spectra of a 1,9-acyl−alkyl biradical were obtained at room temperature in benzene and in liquid (950 psi) carbon dioxide (CO2) solutions. The spin exchange interaction (J) in this biradical is negative and larger in magnitude than the hyperfine interaction (q). This leads to the observation, in both solvents, of spin-correlated radical pair (SCRP) spectra which are net emissive. Spectra obtained at later delay times (>1.5 μs) in CO2 exhibit alternating intensities of their SCRP transitions due to spin relaxation but do not show any significant change in line width. The same effect is observed in benzene, but on a slower time scale. Q-band (35 GHz) experiments in benzene showed that the phenomenon was found to be both field and temperature dependent. It is also chain-length dependent, being much stronger in short biradicals (90%) of polystyrene is obtained in the form of a stable polymer colloid comprised of submicron-sized particles. The particle diameter and distribution of sizes were shown to be dependent on the nature of the stabilizing block copolymer.}, number={8}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Canelas, D. A. and Betts, D. E. and DeSimone, J. M.}, year={1996}, month={Jan}, pages={2818–2821} } @article{shaffer_jones_canelas_desimone_wilkinson_1996, title={Dispersion Polymerizations in Carbon Dioxide Using Siloxane-Based Stabilizers}, volume={29}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma9516798}, DOI={10.1021/ma9516798}, abstractNote={A commercially available poly(dimethylsiloxane) macromonomer has been used to stabilize the dispersion polymerization of MMA in liquid and supercritical CO 2 and of styrene in supercritical C O 2 . Purification of the PMMA obtained showed that only a fraction of the macromonomer added to the polymerization actually copolymerized}, number={7}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Shaffer, K. A. and Jones, T. A. and Canelas, D. A. and DeSimone, J. M. and Wilkinson, S. P.}, year={1996}, month={Jan}, pages={2704–2706} } @article{belu_desimone_linton_lange_friedman_1996, title={Evaluation of matrix-assisted laser desorption ionization mass spectrometry for polymer characterization}, volume={7}, ISSN={1044-0305 1879-1123}, url={http://dx.doi.org/10.1016/1044-0305(95)00589-7}, DOI={10.1016/1044-0305(95)00589-7}, abstractNote={A protocol for the preparation of polymeric samples for time-of-flight matrix-assisted laser desorption ionization mass spectrometry (TOF-MALDI-MS) analysis was developed. Dithranol was identified as a good matrix for polystyrene (PS), and the addition of silver for cationization of molecules was determined to be necessary. Based on this preparative method, low molecular weight samples of other polymers [polyisoprene, polybutadiene, poly(ethylene oxide), poly(methyl methacrylate), and polydimethylsiloxane] were analyzed with molecular weights up to 49 ku. The effects of laser intensity were determined to influence the molecular weight distribution of intact oligomers, most significantly for low molecular weight polymers. Linear and reflectron modes of analysis were evaluated; better signal intensity and resolution were obtained in the reflectron mode. The TOF-MALDI-MS measurements are compared with time-of-flight secondary ion mass spectrometry (TOF-SIMS) and gel permeation chromatography (GPC) for the same polymers. The M n values calculated by TOF-MALDI-MS consistently are higher than values calculated by TOF-SIMS for all classes of polymers with molecular weights up to 8 ku. The molecular weights of the PS calculated from TOF-MALDI-MS are in good agreement with GPC (±10%). The composition of the terminal group on a polymer chain may affect the ion yields. The ion yields of intact oligomers were evaluated as a function of end group composition for both TOF-MALDI-MS and TOF-SIMS. The slight disparity of results between TOF-SIMS and TOF-MALDI-MS for the perfluoroalkyl-terminated PS suggests that the oligomers are desorbed preferentially from the surface in the TOF-SIMS analysis, rather than having an increased ionization probability.}, number={1}, journal={Journal of the American Society for Mass Spectrometry}, publisher={Springer Nature}, author={Belu, A. M. and DeSimone, J. M. and Linton, R. W. and Lange, G. W. and Friedman, R. M.}, year={1996}, month={Jan}, pages={11–24} } @article{mas_jaaba_schué_bellu_kassis_linton_desimone_1996, title={Modification of poly[(3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)] film surfaces in an oxygen low pressure plasma}, volume={197}, ISSN={1022-1352 1521-3935}, url={http://dx.doi.org/10.1002/macp.1996.021970723}, DOI={10.1002/macp.1996.021970723}, abstractNote={AbstractPoly[(3‐hydroxybutyric acid)‐co‐(3‐hydroxyvaleric acid)] (91:9 mass‐%) (P(HB‐co‐9% HV)) film surfaces were modified by an oxygen plasma treatment (75 W, 50 Pa, 5 min). The number of oxygen atoms increases about 12–13% and the polar component of the surface energy increases from 6.3 to 21 mN · m−1. However, the wettability is stable only after 60 days. Untreated and treated film surfaces are studied by means of X‐ray photoelectron spectroscopy with two different depth analyses. With storage time, the oxygen contents of the modified film is constant at a take‐off angle of 20° but decreases to the initial value at a take‐off angle of 70°. The superficial layer of the polymer film between the top of the film to a depth of 10 nm is divided into three superimposing zones. The interpretation is supported by motions of modified macromolecular chains and buried polar groups, chain cleavage and the formation of low‐molecular‐weight molecules which leads to a decrease of the glass transition temperature (plasticizer effect) and migration of short chains from the lowest modified zone toward the surface.}, number={7}, journal={Macromolecular Chemistry and Physics}, publisher={Wiley}, author={Mas, André and Jaaba, Hassan and Schué, François and Bellu, Anna Maria and Kassis, Camille and Linton, Richard and Desimone, Joseph Mark}, year={1996}, month={Jul}, pages={2331–2341} } @article{chillura-martino_triolo_mcclain_combes_betts_canelas_desimone_samulski_cochran_londono_et al._1996, title={Neutron scattering characterization of homopolymers and graft-copolymer micelles in supercritical carbon dioxide}, volume={383}, ISSN={0022-2860}, url={http://dx.doi.org/10.1016/s0022-2860(96)09260-5}, DOI={10.1016/s0022-2860(96)09260-5}, abstractNote={Superficial fluids (SCF) are becoming an attractive alternative to the liquid solvents traditionally used as polymerization media [1]. As the synthesis proceeds, a wide range of colloidal aggregates form, but there has hitherto been no way to measure such structures directly. We have applied small-angle neutron scattering (SANS) to characterize such systems, and although SCF polymerizations are carried out at high pressures, the penetrating power of the neutron beam means that typical cell windows are virtually transparent. Systems studied include polymers soluble in CO2 such as poly(1,1-dihydroperfluorooctyl acrylate) (PFOA), poly(hexafluoropropylene oxide) (PHFPO) and poly(dimethyl siloxane) (PDMS). PFOA has previously [2] been shown to exhibit a positive second virial coefficient (A2), though for PHFPO, A2 appears to be close to zero (104 A2 ⋍ 0 ± 0.2 cm3 g−2 mol). PDMS is soluble on the molecular level only in the limit of dilute solution and seems to form aggregates as the concentration increases (c > 0.01 g cm−3). Typical hydrocarbon polymers are insoluble in CO2, but it has been found that polymerizations may be accomplished via the use of a stabilizer [3]. For example, styrene has been polymerized in CO2 by means of a polystyrene-b-PFOA block copolymer surfactant, which forms micelles in CO2 and is also amenable to SANS characterization. Other amphiphilic surfactant molecules that form micelles include PFOA-g-poly(ethylene oxide) (PFOA-g-PEO) graft copolymers, which swell as the CO2 medium is saturated with water. These systems have been characterized by SANS, by taking advantage of the different contrast options afforded by substituting D2O for H2O. This paper illustrates the utility of SANS to measure molecular dimensions, thermodynamic variables, molecular weights, micelle structures etc. in supercritical CO2.}, number={1-3}, journal={Journal of Molecular Structure}, publisher={Elsevier BV}, author={Chillura-Martino, D. and Triolo, R. and McClain, J.B. and Combes, J.R. and Betts, D.E. and Canelas, D.A. and DeSimone, J.M. and Samulski, E.T. and Cochran, H.D. and Londono, J.D. and et al.}, year={1996}, month={Sep}, pages={3–10} } @article{cooper_desimone_1996, title={Polymer synthesis and characterization in liquid / supercritical carbon dioxide}, volume={1}, ISSN={1359-0286}, url={http://dx.doi.org/10.1016/s1359-0286(96)80100-8}, DOI={10.1016/s1359-0286(96)80100-8}, abstractNote={The use of carbon dioxide as an inert solvent has emerged recently as an important development in polymer chemistry. The past year has seen major advances in the synthesis of a variety of polymeric materials in carbon dioxide. At the same time complementary studies have successfully elucidated the physical behavior of a range of polymers in carbon dioxide solution. Herein we review both synthetic and physical studies that are defining the scope of this approach.}, number={6}, journal={Current Opinion in Solid State and Materials Science}, publisher={Elsevier BV}, author={Cooper, Andrew I and DeSimone, Joseph M}, year={1996}, month={Dec}, pages={761–768} } @article{mistele_thorp_desimone_1996, title={Ring-Opening Metathesis Polymerizations in Carbon Dioxide}, volume={33}, ISSN={1060-1325 1520-5738}, url={http://dx.doi.org/10.1080/10601329608014644}, DOI={10.1080/10601329608014644}, abstractNote={Abstract The polymerization of norbornene was successfully initiated with Ru(H2O)6(tos)2 in a carbon dioxide medium. The resultant poly(norbornene) was prepared with yields and molecular weights comparable to those obtained in other solvent systems. It was also found that the cis/trans ratio of the polymer microstructure could be controlled by the addition of various amounts of methanol to the reaction mixture. A detailed account of the polymerizations is described and believed to be the first example of a ring-opening metathesis polymerization in carbon dioxide.}, number={7}, journal={Journal of Macromolecular Science, Part A}, publisher={Informa UK Limited}, author={Mistele, Chad D. and Thorp, Holden H. and Desimone, Joseph M.}, year={1996}, month={Jul}, pages={953–960} } @article{mcclain_londono_combes_romack_canelas_betts_wignall_samulski_desimone_1996, title={Solution Properties of a CO2-Soluble Fluoropolymer via Small Angle Neutron Scattering}, volume={118}, ISSN={0002-7863 1520-5126}, url={http://dx.doi.org/10.1021/ja952750s}, DOI={10.1021/ja952750s}, abstractNote={In this communication, we report the first characterization of solutions of a high molecular weight polymer in supercritical CO{sub 2} by small-angle neutron scattering (SANS). It is shown that small-angle neutron scattering gives key molecular parameters of an amorphous fluoropolymer in supercritical CO{sub 2}, i.e., the molecular weight, radius of gyration, and second virial coefficient, and thereby gives insights into a polymer chain`s behavior in this unique solvent. The positive sign of the second virial coefficients indicate that this medium is a good solvent - there is no evidence of a collapsed chain conformation. In fact, we conclude from the SANS data that, in CO{sub 2}, the poly(FOA) chain dimensions are expanded relative to those characteristic of its melt. 29 refs., 2 figs., 1 tab.}, number={4}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={McClain, J. B. and Londono, D. and Combes, J. R. and Romack, T. J. and Canelas, D. A. and Betts, D. E. and Wignall, G. D. and Samulski, E. T. and DeSimone, J. M.}, year={1996}, month={Jan}, pages={917–918} } @article{kapellen_mistele_desimone_1996, title={Synthesis of Poly(2,6-dimethylphenylene oxide) in Carbon Dioxide}, volume={29}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma951299m}, DOI={10.1021/ma951299m}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTSynthesis of Poly(2,6-dimethylphenylene oxide) in Carbon DioxideK. K. Kapellen, C. D. Mistele, and J. M. DeSimoneView Author Information CB #3290, Venable and Kenan Laboratories, Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 Cite this: Macromolecules 1996, 29, 1, 495–496Publication Date (Web):January 1, 1996Publication History Received31 August 1995Revised27 October 1995Published online1 January 1996Published inissue 1 January 1996https://pubs.acs.org/doi/10.1021/ma951299mhttps://doi.org/10.1021/ma951299mrapid-communicationACS PublicationsCopyright © 1996 American Chemical SocietyRequest reuse permissionsArticle Views215Altmetric-Citations36LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Amines,Inorganic carbon compounds,Oxides,Polymers,Pyridines Get e-Alerts}, number={1}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Kapellen, K. K. and Mistele, C. D. and DeSimone, J. M.}, year={1996}, month={Jan}, pages={495–496} } @inbook{betts_mcclain_desimone_1996, title={The importance of surfactants for polymerizations in carbon dioxide}, ISBN={9780444824752}, ISSN={0921-8610}, url={http://dx.doi.org/10.1016/s0921-8610(96)80006-9}, DOI={10.1016/s0921-8610(96)80006-9}, abstractNote={Publisher Summary This chapter describes the effects of various surfactant and stabilizer systems as they apply to polymerizations in CO 2 . For CO 2 to be an effective continuous phase for polymerizations, heterogeneous reaction systems must necessarily be developed analogous to classical emulsion, inverse emulsion, dispersion, suspension, and precipitation polymerization processes. With some highly reactive monomers, such as acrylic acid and tetrafluoroethylene, free-radical precipitation polymerization can afford polymers with high yields and molecular weight. However, many industrial monomers require the utilization of surfactant stabilized reaction conditions. This chapter discusses the utilization of nonionic—homopolymer, block copolymer, and reactive macromonomer—surfactants consisting of covalently bound CO 2 -philic and CO 2 -phobic segments in the dispersion polymerization of various CO 2 -insoluble polymers. These reactions produce a stabilized polymer colloid in CO 2 solution and dry, free flowing powders after isolation.}, booktitle={High Pressure Chemical Engineering, Proceedings of the 3rd International Symposium on High Pressure Chemical Engineering}, publisher={Elsevier}, author={Betts, D.E. and McClain, J.B. and DeSimone, J.M.}, year={1996}, pages={23–30} } @article{dukes_forbes_jeevarajan_belu_desimone_linton_sheares_1996, title={Useful Model Systems for the Study of SRN1 Chemistry in the Synthesis of Poly(arylene ether ketone)s}, volume={29}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma951381h}, DOI={10.1021/ma951381h}, abstractNote={Factors contributing to the occurrence of the SRN1 reaction during the synthesis of poly(arylene ether ketone)s are studied using a variety of analytical techniques. Product analysis of polymerization reactions and magnetic resonance studies on photochemical model systems were performed. The polymerization of 4,4‘-dichlorobenzophenone with 4,4‘-isopropylidenediphenol under basic conditions was run in four amide solvents:  1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU), 1-methyl-2-pyrrolidinone (NMP), 1,1,3,3-tetramethylurea (TMU) and N,N ‘-dimethylacetamide (DMAc). Molecular weights of the products followed the order Mn(DMAc) > Mn(NMP) > Mn(TMU) > Mn(DMPU). Simulations of time-resolved electron paramagnetic resonance (TREPR) spectra were used to identify the radicals produced by photoinduced hydrogen atom abstraction in each of the four solvents. Transient optical absorption was used to quantify the yield of radicals produced by reaction of triplet benzophenone-d10 with each solvent. Time-of-fl...}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Dukes, Katerina E. and Forbes, Malcolm D. E. and Jeevarajan, Antony S. and Belu, Anna M. and DeSimone, Joseph M. and Linton, Richard W. and Sheares, Valerie V.}, year={1996}, month={Jan}, pages={3081–3089} } @article{kassis_steehler_betts_guan_romack_desimone_linton_1996, title={XPS Studies of Fluorinated Acrylate Polymers and Block Copolymers with Polystyrene}, volume={29}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma951782x}, DOI={10.1021/ma951782x}, abstractNote={X-ray photoelectron spectroscopy (XPS) has been used to investigate the surface characteristics of various novel fluorinated acrylate homopolymers [1,1-dihydroperfluorooctyl acrylate (PFOA), 1,1-dihydroperfluorooctyl methacrylate (PFOMA), 1,1,2,2-tetrahydroperfluorooctyl acrylate (PTAN)] as well as diblock copolymers consisting of both a fluorocarbon block of PFOA and a hydrocarbon block of polystyrene (PS). This technique allows nondestructive depth profiling of the top ∼100 A of a material, providing both elemental composition and chemical state information. Due to the low surface energy of the fluorinated species, its enhanced presence on the surface is of importance in any potential applications. Angle-dependent XPS surface studies were conducted on polymer thick films to monitor surface segregation of the fluorinated component as a function of depth. Fluorine and the fluorine-containing constituents are surface enriched relative to carbon and oxygen from the acrylate portions of the polymers. This ef...}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Kassis, Camille M. and Steehler, Jack K. and Betts, Douglas E. and Guan, Zhibin and Romack, Timothy J. and DeSimone, Joseph M. and Linton, Richard W.}, year={1996}, month={Jan}, pages={3247–3254} } @article{fulton_pfund_mcclain_romack_maury_combes_samulski_desimone_capel_1995, title={Aggregation of Amphiphilic Molecules in Supercritical Carbon Dioxide: A Small Angle X-ray Scattering Study}, volume={11}, ISSN={0743-7463 1520-5827}, url={http://dx.doi.org/10.1021/la00011a014}, DOI={10.1021/la00011a014}, abstractNote={Highly soluble amphiphilic materials are shown to form aggregates in supercritical CO{sub 2}. The strategy for synthesis of these amphiphilic molecules involves incorporating CO{sub 2}-philic segments that, for this study, are perfluorinated alkyl chains. These CO{sub 2} -philic regions function like the hydrocarbon tails of conventional surfactant molecules used in liquid organic solvents. Synthesis and characterization of three different CO{sub 2} amphiphiles are reported. Subsequent small angle X-ray scattering (SAXS) measurements were used to characterize the aggregation of these materials in supercritical CO{sub 2}. Each of the three amphiphiles studied showed a different type of aggregation behavior. A graft copolymer consisting of a CO{sub 2}-philic backbone and CO{sub 2}-phobic grafts associated into a micellar structure in the presence of water to promote hydrogen bonding. These aggregates contain approximately 600 grafts in the core. The commercially available surfactant perfluoroalkylpoly( ethylene oxide), or F(CF{sub 2}){sub 6-10}CH{sub 2} CH{sub 2}O(CH{sub 2}CH{sub 2}O){sub 3-8}H, forms classic reverse micelle structures having radii of about 84 A under the conditions of high pressure required to solubilize the material. A third amphiphile, the semifluorinated alkane diblock molecule F(CF{sub 2}){sub 10}(CH{sub 2}){sub 10}H, may form small aggregates of at most 4 unimers per aggregate. 41 refs., 10 figs.,more » 1 tab.« less}, number={11}, journal={Langmuir}, publisher={American Chemical Society (ACS)}, author={Fulton, John L. and Pfund, David M. and McClain, J. B. and Romack, T. J. and Maury, E. E. and Combes, J. R. and Samulski, E. T. and DeSimone, J. M. and Capel, Malcolm}, year={1995}, month={Nov}, pages={4241–4249} } @article{desimone_1995, title={Branching Out into New Polymer Markets}, volume={269}, ISSN={0036-8075 1095-9203}, url={http://dx.doi.org/10.1126/science.269.5227.1060}, DOI={10.1126/science.269.5227.1060}, abstractNote={One dependable route to the development of a novel, commercially important polymeric material, a substance that will grasp the attention of industrial scientists, is to use commercially available monomers to produce distinctive new materials. Incremental changes in the properties of old materials can sometimes extend commercial markets, but dramatic changes in properties can open up whole new markets. This has now been done by Frechet and co-workers, who, on page 1080 of this issue, describe a fascinating new concept for making use of readily available monomers to synthesize inexpensive new polymeric materials (1). The process by which they do this is branching, or manipulating the topology of the polymer chain. Branching exerts tremendous influence on material properties. The chemical, physical, mechanical, and rheological properties of a material correlate closely with the nature, degree, and distribution of chain branching. For example, polyethylene (PE), one of the most commonly used bulk polymers because of its excellent balance of cost and performance characteristics, can be used in widely different applications when chain branching is varied in degree and kind (Fig. 1). Completely linear PE, also known as high-density polyethylene (HDPE), has a crystalline melting point of 1350C and is used for applications where structural integrity is of utmost importance, such as crates and pallets, bottles, toys, and housewares. A slightly branched version of PE, commonly referred to as low-density polyethylene (LDPE), has a melting temperature of 1 15'C and is used in applications where low-temperature toughness and flexibility is important, such as pipe and packaging applications. Very recently, an amorphous PE was developed (2) that is so highly branched that it cannot crystallize and, as such, makes possible a number of heretofore unimaginable applications for PEs, such as very low temperature elastomers and damping materials. All of the above are PEs but their applications are diversified as a result of their disparate perfor-}, number={5227}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={DeSimone, J. M.}, year={1995}, month={Aug}, pages={1060–1061} } @article{clark_desimone_1995, title={Cationic Polymerization of Vinyl and Cyclic Ethers in Supercritical and Liquid Carbon Dioxide}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00112a059}, DOI={10.1021/ma00112a059}, abstractNote={Vinyl ethers and oxetanes heve been successfully cationically polymerized in CO 2 . These processes become heterogeneous using hydrocarbon vinyl ethers and oxetanes but high molar mass and high conversions can still bve achieved. Homogeneous cationic polymerizations are also possible with fluorocarbon-based alkyl vinyl ether and oxetane monomers. Polymerization occurs without incorporation of CO 2 into the polymer backbone for the systems used herein}, number={8}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Clark, M. R. and DeSimone, J. M.}, year={1995}, month={Apr}, pages={3002–3004} } @article{shaffer_desimone_1995, title={Chain Polymerizations in Inert Near- and Supercritical Fluids}, volume={3}, journal={Trends in Polymer Science}, author={Shaffer, K.A. and DeSimone, J.M.}, year={1995}, pages={146–153} } @article{brookhart_desimone_grant_tanner_1995, title={Cobalt(III)-Catalyzed Living Polymerization of Ethylene: Routes to End-Capped Polyethylene with a Narrow Molar Mass Distribution}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00119a033}, DOI={10.1021/ma00119a033}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCobalt(III)-Catalyzed Living Polymerization of Ethylene: Routes to End-Capped Polyethylene with a Narrow Molar Mass DistributionM. Brookhart, J. M. DeSimone, B. E. Grant, and M. J. TannerCite this: Macromolecules 1995, 28, 15, 5378–5380Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://doi.org/10.1021/ma00119a033RIGHTS & PERMISSIONSArticle Views638Altmetric-Citations99LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (331 KB) Get e-AlertsSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts}, number={15}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Brookhart, M. and DeSimone, J. M. and Grant, B. E. and Tanner, M. J.}, year={1995}, month={Jul}, pages={5378–5380} } @article{hsiao_maury_desimone_mawson_johnston_1995, title={Dispersion Polymerization of Methyl Methacrylate Stabilized with Poly(1,1-dihydroperfluorooctyl acrylate) in Supercritical Carbon Dioxide}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00128a028}, DOI={10.1021/ma00128a028}, abstractNote={The reaction parameters and progress of the dispersion polymerization of methyl methacrylate (MMA) utilizing poly(1,1-dihydroperfluorooctyl acrylate) [poly(FOA)] as a polymeric stabilizer in supercritical CO 2 were investigated. Spherical and relatively uniform polymer particles were formed. Poly(methyl methacrylate) (PMMA) latex particles with diameters ranging from 1.55 to 2.86 μm were obtained with poly(FOA) stabilizer [M w = 1.0 (± 0.4) x 10 6 g/mol] concentration from 16 to 0.24 wt %. Investigations of the particle size and conversion as a function of reaction time indicate that a gel effect occurs between 1 and 2 h of reaction time. In addition, the particle diameter increases with an increase in monomer concentration, presumably due to an increase in the solvency of the reaction medium. Dispersion polymerizations of MMA carried out under different pressures (145-331 bar) produced latex particles with similar diameters, molecular weights, and yields, suggesting that the results are insensitive to the pressure under the reaction conditions investigated. In addition, the phase behaviors of poly-(FOA) were thoroughly investigated. Cloud point experiments indicate lower critical solution temperature (LCST) phase behavior for the poly(FOA)/CO 2 system with much higher polymer solubilities than for hydrocarbon polymers.}, number={24}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Hsiao, Yu-Ling and Maury, Elise E. and DeSimone, Joseph M. and Mawson, Simon and Johnston, Keith P.}, year={1995}, month={Nov}, pages={8159–8166} } @article{mawson_johnston_combes_desimone_1995, title={Formation of Poly(1,1,2,2-tetrahydroperfluorodecyl acrylate) Submicron Fibers and Particles from Supercritical Carbon Dioxide Solutions}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00113a021}, DOI={10.1021/ma00113a021}, abstractNote={Rapid expansion from supercritical solution (RESS) of a crystalline fluoropolymer, poly(1,1,2,2-tetrahydroperfluorodecyl acrylate) or poly(TA-N), in carbon dioxide produces submicron to several micron sized particles and fibers. The understanding of the RESS mechanism has been clarified by careful design of experimental variables and procedures. The concentration of the poly(TA-N)/CO 2 solution was held constant (at 0.5 and 2.0 wt %), the solution cloud point curves were obtained, the pre-expansion temperature was varied above and below the cloud point, and the length to diameter (L/D) ratio of the nozzle was varied from 8.5 to 508. The morphology is explained in terms of the location of phase separation within the expansion nozzle. The L/D is the most influential variable for achieving a transition from particles or fibers. In most cases, manipulation of the solution concentration and the pre-expansion temperature did not produce this transition but did have a large effect on the sizes of the particles and fibers. These results are an important step in demonstrating CO 2 -based spray processes which do not require any volatile organic solvents}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Mawson, Simon and Johnston, Keith P. and Combes, James R. and DeSimone, Joseph M.}, year={1995}, month={Apr}, pages={3182–3191} } @article{romack_combes_desimone_1995, title={Free-Radical Telomerization of Tetrafluoroethylene in Supercritical Carbon Dioxide}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00109a057}, DOI={10.1021/ma00109a057}, abstractNote={It is shown that CO 2 is an exceptional medium in which to perform free-radical telomerizations of tetrafluoroethylene using perfluoroalkyl iodide telogens without chain transfer to solvents which plagues most all other solvent choices}, number={5}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Romack, T. J. and Combes, J. R. and DeSimone, J. M.}, year={1995}, month={Sep}, pages={1724–1726} } @article{romack_kipp_desimone_1995, title={Polymerization of Tetrafluoroethylene in a Hybrid Carbon Dioxide/Aqueous Medium}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00128a066}, DOI={10.1021/ma00128a066}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolymerization of Tetrafluoroethylene in a Hybrid Carbon Dioxide/Aqueous MediumT. J. Romack, B. E. Kipp, and J. M. DeSimoneCite this: Macromolecules 1995, 28, 24, 8432–8434Publication Date (Print):November 1, 1995Publication History Published online1 May 2002Published inissue 1 November 1995https://pubs.acs.org/doi/10.1021/ma00128a066https://doi.org/10.1021/ma00128a066research-articleACS PublicationsRequest reuse permissionsArticle Views403Altmetric-Citations25LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts}, number={24}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Romack, T. J. and Kipp, B. E. and DeSimone, J. M.}, year={1995}, month={Nov}, pages={8432–8434} } @article{romack_maury_desimone_1995, title={Precipitation Polymerization of Acrylic Acid in Supercritical Carbon Dioxide}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00108a017}, DOI={10.1021/ma00108a017}, abstractNote={We report the successful precipitation polymerization of acrylic acid in supercritical carbon dioxide at pressures ranging from 125 to 345 bar utilizing AIBN as a free radical initiator. Analyses by GPC and SEM indicate that for the pressure range studied there is no appreciable effect on product molecular weight, molecular weight distribution, or particle size or morphology. In addition, effective molecular weight control was demonstrated for precipitation polymerizations of acrylic acid in CO 2 through the use of ethyl mercaptan as a chain transfer agent.}, number={4}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Romack, T. J. and Maury, E. E. and DeSimone, J. M.}, year={1995}, month={Jul}, pages={912–915} } @article{wignall_affholter_bunick_desimone_hunt_menceloglu_samulski_1995, title={Synthesis and SANS Structural Characterization of Polymer-Substituted Fullerenes (Flagellenes)}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00122a003}, DOI={10.1021/ma00122a003}, abstractNote={Small-angle neutron scattering (SANS) has been shown to be an appropriate technique for the structural characterization of fullerenes in solvents with strong SANS contrast (e.g., CS 2 ) [Affholter, K. A. ; Henderson, S. J. ; Wignall, G. D. ; Bunick, G. J. ; Haufler, R. E. ; Compton, R. N. J. Chem. Phys. 1993, 99, 9224]. Since deuterated solvents (e.g., toluene-d 8 ) have a high scattering length density (SLD) which is close to that of C 60 and C 70 fullerenes, there is virtually no SANS contrast with the solvent, and these particles are practically invisible in such media. On the other hand, the negative scattering length of hydrogen means that the SLD of 1 H-containing materials is much lower, so they have a strong contrast with toluene-d 8 . Thus, SANS makes it possible to study the sizes and shapes of polymer-substituted fullerenes (flagellenes) [Samulski, E. T. ; DeSimone, J. M. ; Hung, M. O., Jr. ; Menceloglu, Y. Z. ; Jarnagin, R. C. ; York, G. A. ; Labat, K. B. ; Wang, H. Chem. Mater. 1992, 4, 1153]. Mono- and dipolystyrene-substituted C 60 were synthesized via termination of living anionic polymerization of styrene in an optimization of our previous work [Samulski et al.]. These materials were characterized by gel permeation chromatography (GPC) and small-angle neutron scattering (SANS). The extrapolated cross section at zero angle of scatter [dΣ/dΩ(0)] is a function of the number of pendant chains, so SANS can be used to assess the number of arms which are covalently attached to the fullerene core. Close agreement (±4%) between the measured and calculated values of dΣ/dΩ(0) and with independent estimates of the radius of gyration (R g ) and second virial coefficient (A 2 ) for a linear polystyrene calibration sample serves as a cross check on the validity of this methodology.}, number={18}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Wignall, G. D. and Affholter, K. A. and Bunick, G. J. and DeSimone, J. M. and Hunt, M. O. and Menceloglu, Y. Z. and Samulski, E. T.}, year={1995}, month={Aug}, pages={6000–6006} } @article{romack_desimone_treat_1995, title={Synthesis of Tetrafluoroethylene-Based, Nonaqueous Fluoropolymers in Supercritical Carbon Dioxide}, volume={28}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00128a065}, DOI={10.1021/ma00128a065}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of Tetrafluoroethylene-Based, Nonaqueous Fluoropolymers in Supercritical Carbon DioxideT. J. Romack, J. M. DeSimone, and T. A. TreatCite this: Macromolecules 1995, 28, 24, 8429–8431Publication Date (Print):November 1, 1995Publication History Published online1 May 2002Published inissue 1 November 1995https://pubs.acs.org/doi/10.1021/ma00128a065https://doi.org/10.1021/ma00128a065research-articleACS PublicationsRequest reuse permissionsArticle Views485Altmetric-Citations71LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts}, number={24}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Romack, T. J. and DeSimone, J. M. and Treat, T. A.}, year={1995}, month={Nov}, pages={8429–8431} } @article{peters_belu_linton_dupray_meyer_desimone_1995, title={Termination of Living Anionic Polymerizations Using Chlorosilane Derivatives: A General Synthetic Methodology for the Synthesis of End-Functionalized Polymers}, volume={117}, ISSN={0002-7863}, url={http://dx.doi.org/10.1021/ja00117a008}, DOI={10.1021/ja00117a008}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTermination of Living Anionic Polymerizations Using Chlorosilane Derivatives: A General Synthetic Methodology for the Synthesis of End-Functionalized PolymersM. A. Peters, A. M. Belu, R. W. Linton, L. Dupray, T. J. Meyer, and J. M. DeSimoneCite this: J. Am. Chem. Soc. 1995, 117, 12, 3380–3388Publication Date (Print):March 1, 1995Publication History Published online1 May 2002Published inissue 1 March 1995https://pubs.acs.org/doi/10.1021/ja00117a008https://doi.org/10.1021/ja00117a008research-articleACS PublicationsRequest reuse permissionsArticle Views1517Altmetric-Citations96LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts}, number={12}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Peters, M. A. and Belu, A. M. and Linton, R. W. and Dupray, L. and Meyer, T. J. and DeSimone, J. M.}, year={1995}, month={Mar}, pages={3380–3388} } @article{rix_barborak_wagner_tahliani_desimone_brookhart_elder_1995, title={Transition metal catalyzed alternating copolymerizations of olefins and co}, volume={98}, ISSN={1022-1360}, url={http://dx.doi.org/10.1002/masy.19950980118}, DOI={10.1002/masy.19950980118}, abstractNote={AbstractWell defined Pd(II) catalysts of the type (N′N)Pd(CH3)(Solv.)+ B(Arf)4‐ (Arf = −3, 5‐(CF3)2C6H3) have been prepared for living alternating copolymerizations of olefins with CO. This talk will focus on the mechanistic details of chain growth as elucidated by 1H and 13C NMR spectroscopy, model studies of key migratory insertion steps and synthesis and properties of various copolymers and block copolymers based on styrenes, CH2=CHC6H4X [X = p‐C(CH3)3, p‐OC(O)CH3, p‐OC(O)C‐t‐Bu), p‐NHC(O)(C‐t‐Bu)]. Use of the catalysts based on the C2 symmetric, homochiral ligand 2, 2'‐bis[2‐[4(S)‐(Alkyl)‐1, 3‐oxazolinyl]]propane [Alkyl = CH3, CH(CH3)2] produces a copolymer, 1, with a highly isotactic microstructure and high optical activity in contrast to achiral ligands such as 1,10‐phenanthroline which produce copolymers with predominantly syndiotactic microstructure.}, number={1}, journal={Macromolecular Symposia}, publisher={Wiley}, author={Rix, F. and Barborak, J. and Wagner, M. and Tahliani, S. and Desimone, J. and Brookhart, M. and Elder, D.}, year={1995}, month={Jul}, pages={219–219} } @article{desimone_maury_menceloglu_mcclain_romack_combes_1994, title={Dispersion Polymerizations in Supercritical Carbon Dioxide}, volume={265}, ISSN={0036-8075 1095-9203}, url={http://dx.doi.org/10.1126/science.265.5170.356}, DOI={10.1126/science.265.5170.356}, abstractNote={ Conventional heterogeneous dispersion polymerizations of unsaturated monomers are performed in either aqueous or organic dispersing media with the addition of interfacially active agents to stabilize the colloidal dispersion that forms. Successful stabilization of the polymer colloid during polymerization results in the formation of high molar mass polymers with high rates of polymerization. An environmentally responsible alternative to aqueous and organic dispersing media for heterogeneous dispersion polymerizations is described in which supercritical carbon dioxide (CO 2 ) is used in conjunction with molecularly engineered free radical initiators and amphipathic molecules that are specifically designed to be interfacially active in CO 2 . Conventional lipophilic monomers, exemplified by methyl methacrylate, can be quantitatively (>90 percent) polymerized heterogeneously to very high degrees of polymerization (>3000) in supercritical CO 2 in the presence of an added stabilizer to form kinetically stable dispersions that result in micrometer-sized particles with a narrow size distribution. }, number={5170}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={DeSimone, J. M. and Maury, E. E. and Menceloglu, Y. Z. and McClain, J. B. and Romack, T. J. and Combes, J. R.}, year={1994}, month={Jul}, pages={356–359} } @article{belu_hunt_desimone_linton_1994, title={End-Functionalized Polymers. 2. Quantification of Functionalization by Time-of-Flight Secondary Ion Mass Spectrometry}, volume={27}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00085a037}, DOI={10.1021/ma00085a037}, abstractNote={The applicability of time-of-flight secondary ion mass spectrometry (TOF-SIMS) for quantification of functionalization is demonstrated using five 1.0×10 3 g/mol polystyrene samples which were synthesized by living anionic polymerization. The polymerizations were functionally terminated to various extents (0, 25, 50, 75, and 100%) by using sequential termination techniques with chlorodimethylphenylsilane and methanol. Two distinct molecular weight distributions of intact oligomer signals are resolved in the TOF-SIMS spectra resulting from the functionalized and unfunctionalized (protonated) oligomer species in each sample}, number={7}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Belu, A. M. and Hunt, M. O. and DeSimone, J. M. and Linton, R. W.}, year={1994}, month={Mar}, pages={1905–1910} } @article{guan_desimone_1994, title={Fluorocarbon-Based Heterophase Polymeric Materials. 1. Block Copolymer Surfactants for Carbon Dioxide Applications}, volume={27}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00098a002}, DOI={10.1021/ma00098a002}, abstractNote={Poly(1,1-dihydroperfluorooctyl acrylate) (PFOA) based block copolymers were synthesized for use as lipophilic/«CO 2 -philic» surfactants for CO 2 applications. The first step was the synthesis of telechelic polystyrenes capped with the N,N-diethyldithrocarbamate group (TD-PS) using the iniferter method. The 3-D GPC analysis provided detailed information on the percent functionality of end groups across the molar mass distribution. The results showed that the functionality was constant for different chain lengths. Block copolymers were synthesized by sunsequent polymerization of FOA using telechelic polystyrene as macroinitiator}, number={20}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Guan, Zhibin and DeSimone, J. M.}, year={1994}, month={Sep}, pages={5527–5532} } @article{combes_guan_desimone_1994, title={Homogeneous free-radical polymerizations in carbon dioxide. 3. Telomerization of 1,1-difluoroethylene in supercritical carbon dioxide}, volume={27}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00081a036}, DOI={10.1021/ma00081a036}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHomogeneous free-radical polymerizations in carbon dioxide. 3. Telomerization of 1,1-difluoroethylene in supercritical carbon dioxideJ. R. Combes, Z. Guan, and J. M. DeSimoneCite this: Macromolecules 1994, 27, 3, 865–867Publication Date (Print):January 1, 1994Publication History Published online1 May 2002Published inissue 1 January 1994https://pubs.acs.org/doi/10.1021/ma00081a036https://doi.org/10.1021/ma00081a036research-articleACS PublicationsRequest reuse permissionsArticle Views218Altmetric-Citations55LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts}, number={3}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Combes, J. R. and Guan, Z. and DeSimone, J. M.}, year={1994}, month={May}, pages={865–867} } @article{phillips_sheares_samulski_desimone_1994, title={Isomeric Poly(benzophenone)s: synthesis of Highly Crystalline Poly(4,4'-benzophenone) and Amorphous Poly(2,5-benzophenone), a Soluble Poly(p-phenylene) Derivative}, volume={27}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00086a064}, DOI={10.1021/ma00086a064}, abstractNote={Abstract : Nickel-catalyzed polymerization which employs the coupling of isomeric dichlorobenzophenones is described. The polymerization utilizes inexpensive readily available monomers, 4,4'-dichlorobenzophenone (4,4'-DCBP) and 2,5-dichlorobenzophenone (2,5-DCBP). The poly(4,4'-benzophenone) can be derivatized to be soluble during the synthesis by the use of a ketimine precursor that is subsequently hydrolyzed to give the target material. The polymerization of 2,5-dichlorobenzophenone yields a soluble derivative of poly(p-phenylene). The resulting polymers were characterized to confirm the composition, molar mass, and thermal properties. The Ni(O) catalyzed route proves to be facile and economically feasible and opens the way to a large variety of heterocyclic and phenyl-based homo- and copolymers. 4,4'- dichlorobenzophenone, Hydrolyzed, Molar mass, Thermal.}, number={8}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Phillips, R. W. and Sheares, V. V. and Samulski, E. T. and DeSimone, J. M.}, year={1994}, month={Apr}, pages={2354–2356} } @article{affholter_bunick_desimone_hunt_menceloglu_samulski_wignall_1994, title={Structural Characterization of a Polymer Substituted Fullerene (Flagellene) by Small Angle Neutron Scattering}, volume={359}, ISSN={0272-9172 1946-4274}, url={http://dx.doi.org/10.1557/proc-359-335}, DOI={10.1557/proc-359-335}, abstractNote={ABSTRACTSmall-angle neutron scattering (SANS) can structurally characterize fullerenes1in solvents with strong SANS contrast (e.g. CS2). Deuterated solvents (e.g. toluene-d8) have a high scattering length density (SLD), which is close to that of C60and C70moieties. Hence, there is virtually no SANS contrast with the solvent and these particles are practically “invisible” in such media. On the other hand, the negative scattering length of hydrogen means that the SLD of H1-containing materials is much lower, so they have strong contrast with toluene-d8. Thus, SANS makes it possible to study the size and shapes of modified buckyballs such as the polymer-substituted fullerenes, or flagellenes2. These consist of C60cores to which 1-4 polystyrene chains (with a molecular weight, MW ≃ 2000) are attached. The extrapolated cross section at zero angle of scatter [dΣ/dΩ(0)]s is a function of the number of pendant chains, so SANS can be used to assess the number of “arms” which are covalently attached to the fullerene “sphere”. Close agreement (± 4%) between the measured and calculated values of dΣ/dΩ(0) along with independent estimates of the radius of gyration (Rg) and second virial coefficient (A2) for a calibration linear polystyrene sample serves as a cross check on the validity of this methodology.}, journal={MRS Proceedings}, publisher={Cambridge University Press (CUP)}, author={Affholter, K.A. and Bunick, G.J. and Desimone, J.M. and Hunt, M.O., JR. and Menceloglu, Y.Z. and Samulski, E.T. and Wignall, G.D.}, editor={Bernier, P. and Bethune, D.S. and Chiang, L.Y. and Ebbesen, T.W. and Metzger, R.M.Editors}, year={1994}, pages={335–340} } @article{sheares_desimone_hedrick_carter_labadie_1994, title={Thiophene-based poly(arylene ether)s: 5. Imide-arylene ether statistical copolymers}, volume={35}, ISSN={0032-3861}, url={http://dx.doi.org/10.1016/0032-3861(94)90562-2}, DOI={10.1016/0032-3861(94)90562-2}, abstractNote={Abstract Imide-aryl ether thiophene copolymers were prepared and their thermal and mechanical properties were investigated. A key feature of these copolymers is the incorporation of the 2,5-thiophene moiety using 5,5′-bis[(3-aminophenoxy)thienyl-2] Ketone or 5,5′-bis[(4-aminophenoxy)thienyl-2] ketone as diamines in polyimide syntheses. The preparation of these thiophene diamines involved the nucleophilic aromatic substitution of bis(5-chlorothienyl-2) ketone with either 3- or 4-aminophenol in N -methyl-2-pyrrolidinone using potassium carbonate. These diamines were reacted with various compositions of pyromellitic dianhydride and 4,4′-oxydianiline to synthesize the desired poly(amic acid)s. Films were cast and cured (300°C) to effect the imide formation, and the resulting films showed tough ductile mechanical properties with high glass transition temperatures that decreased with increasing thiophene diamine content.}, number={17}, journal={Polymer}, publisher={Elsevier BV}, author={Sheares, V.V. and DeSimone, J.M. and Hedrick, J.L. and Carter, K.R. and Labadie, J.W.}, year={1994}, month={Aug}, pages={3782–3785} } @article{desimone_sheares_1993, title={Clarification of the introduction to the communication "New polymerization methodology: synthesis of thiophene-based poly(arylene ether ketones)"}, volume={26}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00062a042}, DOI={10.1021/ma00062a042}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTClarification of the introduction to the communication "New polymerization methodology: synthesis of thiophene-based poly(arylene ether ketones)"J. M. DeSimone and V. V. ShearesCite this: Macromolecules 1993, 26, 10, 2642Publication Date (Print):May 1, 1993Publication History Published online1 May 2002Published inissue 1 May 1993https://pubs.acs.org/doi/10.1021/ma00062a042https://doi.org/10.1021/ma00062a042research-articleACS PublicationsRequest reuse permissionsArticle Views64Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts}, number={10}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={DeSimone, J. M. and Sheares, V. V.}, year={1993}, month={May}, pages={2642–2642} } @article{hunt_belu_linton_desimone_1993, title={End-functionalized polymers. 1. Synthesis and characterization of perfluoroalkyl-terminated polymers via chlorosilane derivatives}, volume={26}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00070a020}, DOI={10.1021/ma00070a020}, abstractNote={Surface-active, perfluoroalkyl-terminated block copolymers were synthesized and characterized. These heterophase block copolymers were made by terminating a variety of living anionic polymerizations with a chlorosilane derivative containing a perfluoroalkyl group. This synthetic methodology was successfully applied to the anionic polymerization of styrene and 1,3-dienes. Perfluoroalkyl-terminated poly(olefin)s were obtained via hydrogenation of the unsaturated poly(diene) materials. Excellent control of the molar mass, molar mass distribution, and functionality was verified using conventional characterization techniques such as gel permeation chromatography, NMR, and elemental analysis. In addition, time-of-flight secondary ion mass spectrometry (TOF-SIMS) was employed to characterize the absolute molar masses and molar mass distributions and also the extent of functionalization.}, number={18}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Hunt, M. O. and Belu, A. M. and Linton, R. W. and DeSimone, J. M.}, year={1993}, month={Aug}, pages={4854–4859} } @article{guan_combes_menceloglu_desimone_1993, title={Homogeneous free radical polymerizations in supercritical carbon dioxide: 2. Thermal decomposition of 2,2'-azobis(isobutyronitrile)}, volume={26}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00063a003}, DOI={10.1021/ma00063a003}, abstractNote={The thermal decomposition of 2,2'-azobis(isobutyronitrile) (AIBN) in supercritical CO 2 was investigated by using UV/vis spectroscopic methods. The measured solvent strength of supercritical CO 2 aided in the interpretation of the observed effects of density on the decomposition kinetics. Analysis of the decomposition products indicated that supercritical CO 2 is an acceptable medium to conduct free radical reactions. The decomposition rate and initiation efficiency of AIBN in supercritical CO 2 as a function of pressure and temperature were determined and modeled using Kirkwood solution theory. The initiation efficiency of AIBN in supercritical CO 2 was shown to be ca. 1.5 times higher than that measured in benzene and was found to be invariant with pressure}, number={11}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Guan, Zhibin and Combes, J. R. and Menceloglu, Y. Z. and DeSimone, J. M.}, year={1993}, month={May}, pages={2663–2669} } @article{desimone_maury_lemert_combes_1993, title={Near- and supercritical fluid solvents for living anionic polymerizations}, volume={67}, ISSN={0258-0322}, url={http://dx.doi.org/10.1002/masy.19930670120}, DOI={10.1002/masy.19930670120}, abstractNote={AbstractNear‐ and supercritical fluids are investigated as solvents for anionic polymerizations of 1,3‐dienes. Solvent strength (solubility parameter) of mixtures of light hydrocarbons containing cyclohexane is shown to be adjustable using solvatochromic probe methods. The results indicate that these mixtures have solubility parameter values that are lower than conventional liquid solvents and represent a regime of solvent strength that has remained unexplored for ionic polymerizations. The anionic initiator 3‐methyl‐1,1‐diphenyl‐pentyllithium (MDPPL) was shown to be soluble in supercritical ethane and that its ultraviolet/visible absorption maximum was sensitive to systematic density changes of the supercritical fluid induced by pressure profiling. These results were extended to the anionic polymerization of isoprene in butane/cyclohexane mixtures.}, number={1}, journal={Makromolekulare Chemie. Macromolecular Symposia}, publisher={Wiley}, author={Desimone, J.M. and Maury, E.E. and Lemert, R.M. and Combes, J. R.}, year={1993}, month={Mar}, pages={251–260} } @article{brennan_wang_desimone_stompel_samulski_1993, title={Thiophene-based poly(arylene ether ketone)s: 2. Thermal and mechanical properties of amorphous systems using bis(p-fluorobenzoyl)aryl monomers}, volume={34}, ISSN={0032-3861}, url={http://dx.doi.org/10.1016/0032-3861(93)90366-i}, DOI={10.1016/0032-3861(93)90366-i}, abstractNote={A series of high molar mass and controlled molar mass poly(aryl ether ketone)s were synthesized based on bis(p-fluoro-benzoyl)aryl monomers and 4,4'isopropylidenediphenol.The central aromatic unit of the activated bishalide was varied to include 1,4 phenylene, 2,5 thiophene, and 1,3 phenylene to systematically change the exocyclic bond angle from 1800 to 1480 to 1200, respectively.The thermal, dynamic mechanical and mechanical properties of the three polymers were determined for the controlled molar mass materials.The glass transition temperature of the controlled molar mass 2,5-thiophene based polymer was 147 0 C compared to 149 0 C for 1,3-phenylene based polymer and 162 0 C for the 1,4-phenylene based polymer.The thermal stability of poly(BFTh-BisA) was similar to that of poly(1,3-BFB-BisA) and poly(1,4-BFB-BisA).Two sub T loss dispersions were measured for each of the three polymers.The pronounced y relaxation for poly(BFTh-BisA), poly(1,4-BFB-BisA), and poly(1,3-BFB-BisA), has an activation energy of 7.5, 9.0, and 10 kcal/mole, respectively.The activation energy of a dispersion for poly(BFTh-BisA) is 16 kcal/mole.The Young's modulus is 2.9 GPa, 3.1 GPa and 3.6 GPa for poly(1,4-BFB-BisA), poly(2,5-BFTh-BisA) and poly(1,3-BFB-BisA), respectively.}, number={4}, journal={Polymer}, publisher={Elsevier BV}, author={Brennan, A.B. and Wang, Y.Q. and DeSimone, J.M. and Stompel, S. and Samulski, E.T.}, year={1993}, month={Feb}, pages={807–812} } @article{archibald_sheares_samulski_desimone_1993, title={Thiophene-based poly(arylene ethers). 4. Synthesis of poly(arylene ether sulfones)}, volume={26}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00077a057}, DOI={10.1021/ma00077a057}, abstractNote={High molecular weight polymer [(C 4 H 2 S)SO 2 PhOPhC(Me) 2 PhO] n is synthesized by nucleophilic displacement of 2-chloro- and 2-fluoro-5-[(4'-chlorophenyl)sulfonyl]thiophene with Bisphenol A. The resulting polymer has a T g of 164°C and a 5% weight loss temperature of 400°C in air and 394°C in nitrogen}, number={25}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Archibald, R. S. and Sheares, V. V. and Samulski, E. T. and DeSimone, J. M.}, year={1993}, month={Dec}, pages={7083–7085} } @article{linton_mawn_belu_desimone_hunt_menceloglu_cramer_benninghoven_1993, title={Time-of-flight secondary ion mass spectrometric analysis of polymer surfaces and additives}, volume={20}, ISSN={0142-2421 1096-9918}, url={http://dx.doi.org/10.1002/sia.740201210}, DOI={10.1002/sia.740201210}, abstractNote={AbstractThis paper presents the application of static time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) to the analysis of polymeric materials, including chemically modified polymers and polymer additives. Throuh the detection of intact functionalized oligomers, analysis of poly(styrene) functionalized with perfluoroalkyl chlorosilane provides confirmation of a successful endgroup termination for a living polymerization. The calculated molecular weight distribution also is in good agreement with chromatrographic results. High mass resolution studies allow monitoring of the hydrogenation of a poly(butadiene) polymer through increases in oligomer mass due to proton addition. The quantitative ToF‐SIMS results for the extent of hydrogenation for a specific oligomer are lower than the values averaged over all oligomers as determined by magnetic resonance. The usefulness of ToF‐SIMS for determination of trace‐level polymer additives is demonstrated for linear low‐density poly(ethylene) (LLDPE). Application of a 150 nm thick evaporated Ag pattern enables in situ detection of the five trace additives present in the LLDPE matrix, and also provides information on additive surface migration and surface oxidation. A study of the silver cationization process for the silver‐patterned LLDPE surface suggests differences in diffusion and/or ionization processes for two additives. This is confirmed with mass‐resolved ion imaging to show the lateral distribution of the silver‐cationized signals for various polymer additive molecular ions. Finally, poly(styrene) (Mn = 1300) coated with a continuous silver overlayer is investigated. The ToF‐SIMS‐determined molecular weight distribution shifts to lower masses, suggesting the greater diffusion of shorter polymer chains through the silver overlayer.}, number={12}, journal={Surface and Interface Analysis}, publisher={Wiley}, author={Linton, R. W. and Mawn, M. P. and Belu, A. M. and DeSimone, J. M. and Hunt, M. O. and Menceloglu, Y. Z. and Cramer, H. G. and Benninghoven, A.}, year={1993}, month={Nov}, pages={991–999} } @article{samulski_desimone_hunt_menceloglu_jarnagin_york_labat_wang_1992, title={Flagellenes: nanophase-separated, polymer-substituted fullerenes}, volume={4}, ISSN={0897-4756 1520-5002}, url={http://dx.doi.org/10.1021/cm00024a011}, DOI={10.1021/cm00024a011}, abstractNote={This paper describes the synthesis and characterization of fusible and soluble polystyrene (PS) adducts of the spheroidal C{sub 60} fullerene and named flagellenes, C{sub 60}(PS){sub x`}, where x is variable (x {ge} 10). These materials spontaneously partition the fullerene moiety into domains in a nanophase-separated glass. Gel permeation chromatography and NMR confirm that mixtures of C{sub 60}(PS){sub x} adducts can be synthesized by adding living PS carbanions (number average molar mass = 2000) to C{sub 60}. Transmission electron microscopy shows nanophase-separated morphologies with fullerene-rich domains. The flagellenes could facilitate the processing and fabrication of fullerene-based materials and thereby contribute to the realization of the electronic and optical properties of C{sub 60} in technological applications.}, number={6}, journal={Chemistry of Materials}, publisher={American Chemical Society (ACS)}, author={Samulski, E. T. and DeSimone, J. M. and Hunt, M. O. and Menceloglu, Y. Z. and Jarnagin, R. C. and York, G. A. and Labat, K. B. and Wang, H.}, year={1992}, month={Nov}, pages={1153–1157} } @article{desimone_sheares_1992, title={New polymerization methodology: synthesis of thiophene-based heterocyclic polyethers}, volume={25}, DOI={10.1021/ma00042a033}, abstractNote={Abstract : A new methodology is described for the synthesis of aromatic heterocyclic polyethers which employs thienyl-phenyl ether bond formation as the polymer forming reaction. The efficacy of the new polymerization methodology was first investigated with model compounds where the potassium salt of t-butylphenoxide was found to quantitatively displace the activated chloride on 2benzoyl-5-chlorothiophene to yield 2-benzoyl-5-(4-t-butylphenoxy)thiophene. The model reaction was extended to the synthesis of high polymer using bis(5-chlorothienyl-2)ketone and 4,4'isopropylidenediphenol in an azeotroping mixed solvent system with K2CO3. The resulting polymer was characterized to confirm its composition, structure, and molar mass. This new methodology uses facile synthetic routes and economically feasible starting materials and opens the way to a large variety of heterocyclic, aromatic polyethers which are generally applicable for utilization as advanced materials for structural composites. Thiophene, Heterocyclic polyethers, PEEK, Thermoplastic composites.}, number={16}, journal={Macromolecules}, author={DeSimone, J.M. and Sheares, V.V.}, year={1992}, pages={4235–4236} } @article{brookhart_rix_desimone_barborak_1992, title={Palladium(II) catalysts for living alternating copolymerization of olefins and carbon monoxide}, volume={114}, ISSN={0002-7863}, url={http://dx.doi.org/10.1021/ja00040a082}, DOI={10.1021/ja00040a082}, abstractNote={Several Pd(II) catalyst systems have been reported which effect prefectly alternating copolymerization of olefins with carbon monoxide to yield polyketones [C(O)CH(R)CH{sub 2}]{sub n}. There has been increasing interest in these polymers, particularly the C{sub 2}H{sub 4}/CO copolymer (T{sub m} = 257{degree}C), due to their unusual properties, the low cost of monomers, the present of the carbonyl functionality, and the potential for further functionalization. The catalyst systems used have typically employed Pd(II) salts in methanol or chloroform. We report here the synthesis of well-defined Pd(II) catalysts that operate in aprotic solvents to yield living alternating copolymers of olefins and CO. In situ spectroscopic studies have established mechanistic details including the identity of the catalyst resting state.}, number={14}, journal={Journal of the American Chemical Society}, publisher={American Chemical Society (ACS)}, author={Brookhart, M. and Rix, Francis C. and DeSimone, J. M. and Barborak, James C.}, year={1992}, month={Jul}, pages={5894–5895} } @article{bowden_gozdz_desimone_mcgrath_ito_matsuda_1992, title={Reactive-ion etch resistant polysulfones for microlithography}, volume={53}, ISSN={0258-0322}, url={http://dx.doi.org/10.1002/masy.19920530113}, DOI={10.1002/masy.19920530113}, abstractNote={AbstractThe various chemical approaches aimed at improving the reactive‐ion etch resistance of poly(olefin sulfone)s are described. Resist systems based on incorporation of RIE‐resistant moieties via random copolymerization, blending and block copolymer formation are described and lithographic properties noted.}, number={1}, journal={Makromolekulare Chemie. Macromolecular Symposia}, publisher={Wiley}, author={Bowden, Murrae J. and Gozdz, Antoni S. and DeSimone, Joseph M. and McGrath, James E. and Ito, Seiki and Matsuda, Minoru}, year={1992}, month={Jan}, pages={125–137} } @article{smith_desimone_huang_york_dwight_wilkes_mcgrath_1992, title={Synthesis and characterization of poly(methyl methacrylate)-g-poly(dimethylsiloxane)copolymers. I. Bulk and surface characterization}, volume={25}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00036a002}, DOI={10.1021/ma00036a002}, abstractNote={Poly(dimethylsiloxane) (PDMS) macromonomers of controlled molar masses, narrow molar mass distributions, and high percent functionalities were synthesized through the utilization of the living anionic ring-opening polymerization of hexamethylcyclotrisiloxane. The resultant methacryloxy-functionalized macromonomers were statistically copolymerized with methyl methacrylate to form the title graft copolymers of various chemical compositions. Surface segregation of the low surface energy component, PDMS, was established}, number={10}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Smith, S. D. and DeSimone, J. M. and Huang, H. and York, G. and Dwight, D. W. and Wilkes, G. L. and McGrath, J. E.}, year={1992}, month={May}, pages={2575–2581} } @article{desimone_guan_elsbernd_1992, title={Synthesis of Fluoropolymers in Supercritical Carbon Dioxide}, volume={257}, ISSN={0036-8075 1095-9203}, url={http://dx.doi.org/10.1126/science.257.5072.945}, DOI={10.1126/science.257.5072.945}, abstractNote={Fluoropolymers are used in many technologically demanding applications because of their balance of high-performance properties. A significant impediment to the synthesis of variants of commercially available amorphous fluoropolymers is their general insolubility in most solvents except chlorofluorocarbons (CFCs). The environmental concerns about CFCs can be circumvented by preparing these technologically important materials in supercritical fluids. The homogeneous solution polymerization of highly fluorinated acrylic monomers can be achieved in supercritical carbon dioxide by using free radical methods. In addition, detailed decomposition rates and efficiency factors were measured for azobisisobutyronitrile in supercritical carbon dioxide and were compared to those obtained with conventional liquid solvents.}, number={5072}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={DeSimone, J. M. and Guan, Z. and Elsbernd, C. S.}, year={1992}, month={Aug}, pages={945–947} } @article{desimone_stompel_samulski_wang_brennan_1992, title={Thiophene-containing poly(arylene ether ketones). 1. Polymerization of bis(p-fluorobenzoyl)aryl systems with 4,4'-isopropylidenediphenol}, volume={25}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00035a038}, DOI={10.1021/ma00035a038}, abstractNote={Polymers [PhCO-X-COPhOPhC(CH 3 ) 2 PhO] (X= Ph, C 4 H 2 S) were prepared. All of the polymers were of high molecular weight, including the system using 2,5-bis(p-fluorobenzoyl)thiophene, which indicates the inherent stability of the thiophene-containing monomer to the usual polymerization reaction conditions. The effect of varying the exocyclic bond angle of the central aromatic unit on physical properties was studied. The thiophene-containing poly(arylene ether ketone showed a T g between that of the 1,4- and 1,3-phenylene-based polymers.}, number={9}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={DeSimone, J. M. and Stompel, S. and Samulski, E. T. and Wang, Y. Q. and Brennan, A. B.}, year={1992}, month={Apr}, pages={2546–2550} } @article{desimone_stangle_riffle_mcgrath_1991, title={Aluminium-27 NMR studies of aluminiumporphyrins}, volume={42-43}, ISSN={0258-0322}, url={http://dx.doi.org/10.1002/masy.19910420131}, DOI={10.1002/masy.19910420131}, abstractNote={AbstractAluminium‐27 NMR has been employed to study several different aluminiumporphyrins based on (5, 10, 15, 20‐tetraphenyl)porphyrin (TPPH2). The aluminiumporphyrins were formed by reacting a stoichiometric amount of trialkylaluminium with TPPH2to yield TPPAl‐R. The resulting aluminiumporphyrin was modified by adding a stoichiometric amount of various carboxylic acids to form aluminiumporphyrin carboxylates that had varying steric and electronic effects on the macrocycle.}, number={1}, journal={Makromolekulare Chemie. Macromolecular Symposia}, publisher={Wiley}, author={Desimone, J. M. and Stangle, M. and Riffle, J. S. and McGrath, J. E.}, year={1991}, month={Mar}, pages={373–385} } @article{lemert_desimone_1991, title={Solvatochromic characterization of near- and supercritical ethane, propane, and dimethyl ether using 9-(α-perfluoroheptyl-β,β-dicyano-vinyl)julolidine}, volume={4}, ISSN={0896-8446}, url={http://dx.doi.org/10.1016/0896-8446(91)90007-s}, DOI={10.1016/0896-8446(91)90007-s}, abstractNote={The solvatochromic dye 9(α-perfluoroheptyl-β,β-dicyanovinyl)julolidine is used to characterize the solvent strength of ethane, propane, and dimethyl ether over a pressure range of 35–300 bar at temperatures ranging from 25 to 155 °C. The results are consistent with the concept of clustering of the solvent molecules around the solute near the critical density. The direct relationship between the solvent's local density about the solute and it's isothermal compressibility, is shown to be valid not only at pressures above the critical pressure, but also at pressures below this value. Dimethyl ether is shown to be a highly adjustable solvent worth future consideration in supercritical fluid applications.}, number={3}, journal={The Journal of Supercritical Fluids}, publisher={Elsevier BV}, author={Lemert, Richard M. and Desimone, Joseph M.}, year={1991}, month={Sep}, pages={186–193} } @article{desimone_york_mcgrath_gozdz_bowden_1991, title={Synthesis, bulk, surface and microlithographic characterization of poly(1-butene sulfone)-g-poly(dimethylsiloxane)}, volume={24}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00019a019}, DOI={10.1021/ma00019a019}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis, bulk, surface and microlithographic characterization of poly(1-butene sulfone)-g-poly(dimethylsiloxane)J. M. DeSimone, G. A. York, J. E. McGrath, A. S. Gozdz, and M. J. BowdenCite this: Macromolecules 1991, 24, 19, 5330–5339Publication Date (Print):September 1, 1991Publication History Published online1 May 2002Published inissue 1 September 1991https://doi.org/10.1021/ma00019a019RIGHTS & PERMISSIONSArticle Views243Altmetric-Citations34LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (4 MB) Get e-Alertsclose Get e-Alerts}, number={19}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={DeSimone, J. M. and York, G. A. and McGrath, J. E. and Gozdz, A. S. and Bowden, M. J.}, year={1991}, month={Sep}, pages={5330–5339} } @article{siochi_desimone_hellstern_mcgrath_ward_1990, title={Dilute solution properties of model PMMA-g-PMMA's}, volume={23}, ISSN={0024-9297 1520-5835}, url={http://dx.doi.org/10.1021/ma00223a030}, DOI={10.1021/ma00223a030}, abstractNote={Etude de l'influence du degre de ramification sur les proprietes des solutions diluees de PMMA peignes de meme masse moleculaire. Etude de la validite de l'etalonnage universel pour la determination de la masse moleculaire et la distribution de masse moleculaire de polymeres en peigne}, number={21}, journal={Macromolecules}, publisher={American Chemical Society (ACS)}, author={Siochi, E. J. and DeSimone, J. M. and Hellstern, A. M. and McGrath, J. E. and Ward, Thomas C.}, year={1990}, month={Oct}, pages={4696–4706} } @article{desimone_hellstern_siochi_smith_ward_mcgrath_gallagher_krukonis_1990, title={Homogeneous and multiphase poly(methyl methacrylate) graft polymers via the macromonomer method}, volume={32}, ISSN={0258-0322}, url={http://dx.doi.org/10.1002/masy.19900320105}, DOI={10.1002/masy.19900320105}, abstractNote={AbstractAnionic and group transfer polymerization processes were used to synthesize controlled molecular weight methacryloyloxy functionalized poly(dimethylsiloxane) and poly(methyl methacrylate) macromonomers having a narrow molecular weight distribution and high percent functionality. These macromonomers were anionically copolymerized with methyl methacrylate (MMA) to afford poly(methyl methacrylate)‐graft‐poly(methyl methacrylate) (PMMA‐g‐PMMA) and poly(methyl methacrylate)‐graft‐poly(dimethylsiloxane) (PMMA‐g‐PDMS) polymers having not only narrow molecular weight distribution graft parts but also backbone parts. The PMMA‐g‐PDMS system was fractionated using supercritical chlorodifluoromethane to determine its chemical composition distribution (CCD). The CCD for the PMMA‐g‐PDMS copolymerized in a living manner was substantially more narrow than the free radically copolymerized material. The PMMA‐g‐PMMA system was used to study the dilute solution properties of branched homopolymers. The appropriateness of the universal calibration gel permeation chromatography (GPC) method for branched systems exhibiting long chain branching was reaffirmed.}, number={1}, journal={Makromolekulare Chemie. Macromolecular Symposia}, publisher={Wiley}, author={Desimone, J. M. and Hellstern, A. M. and Siochi, E. J. and Smith, S. D. and Ward, T. C. and McGrath, J. E. and Gallagher, P. M. and Krukonis, V. J.}, year={1990}, month={Feb}, pages={21–45} } @inbook{mcgrath_desimone_hellstern_long_hoover_smith_broske_cho_yoo_wood_et al._1989, place={Washington, D. C}, title={Advances in Heterophase Copolymer Synthesis}, booktitle={Multiphase Macromolecular Systems}, publisher={American Chemical Society}, author={McGrath, J.E. and DeSimone, J.M. and Hellstern, A.M. and Long, T.E. and Hoover, J.M. and Smith, S.D. and Broske, A.D. and Cho, C. and Yoo, Y. and Wood, P. and et al.}, editor={Culbertson, W.Editor}, year={1989}, pages={213–226} } @inproceedings{desimone_york_smith_gozdz_bowden_mcgrath_1989, title={Synthesis and Characterization of Poly(1-butene sulfone)-g-Polydimethylsiloxane): A New Electron-Beam Resist for Two-Layer Lithography}, volume={3}, booktitle={Proceedings of the 3rd International SAMPE Electronics Conference}, author={DeSimone, J.M. and York, G.A. and Smith, S.D. and Gozdz, A.S. and Bowden, M.J. and McGrath, J.E.}, year={1989}, pages={872–881} } @inbook{desimone_hellstern_ward_mcgrath_smith_gallagher_krukonis_stejskal_strakova_kratochvil_1989, place={Washington, D. C}, title={Synthesis, Characterization, and Chemical Composition Distribution Investigations of Graft Copolymers Prepared by the Macromonomer Technique}, booktitle={Multiphase Macromolecular Systems}, publisher={American Chemical Society}, author={DeSimone, J.M. and Hellstern, A.M. and Ward, T.C. and McGrath, J.E. and Smith, S.D. and Gallagher, P.M. and Krukonis, V.J. and Stejskal, J. and Strakova, D. and Kratochvil, P.}, editor={Culbertson, W.Editor}, year={1989}, pages={227–241} } @article{tunnicliffe_desimone, title={A passion for innovation Joseph DeSimone}, number={824}, journal={Chemical Engineer (London, England)}, author={Tunnicliffe, H. and DeSimone, J.}, pages={56–57} } @misc{charpentier_desimone_roberts, title={Apparatus for continuous production of polymers in carbon dioxide}, volume={7,410,620}, number={2008 Aug. 12}, author={Charpentier, P. A. and DeSimone, J. M. and Roberts, G. W.} } @misc{williams_desimone, title={Carbon dioxide-assisted methods of providing biocompatible intraluminal prostheses}, volume={7,285,287}, number={2007 Oct. 23}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Williams, M. S. and DeSimone, J. M.} } @misc{desimone_romack_betts_mcclain, title={Cleaning process using carbon dioxide as a solvent and employing molecularly engineered surfactants}, volume={5,783,082}, number={1998 Jul. 21}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. and Betts, D. E. and McClain, J. B.} } @misc{desimone_romack_betts_mcclain, title={Cleaning process using carbon dioxide as a solvent and employing molecularly engineered surfactants}, volume={5,944,996}, number={1999 Aug. 31}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. and Betts, D. E. and McClain, J. B.} } @misc{desimone_romack_betts_mcclain, title={Cleaning process using carbon dioxide as a solvent and employing molecularly engineered surfactants}, volume={5,866,005}, number={1999 Feb. 2}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. J. and Betts, D. E. and McClain, J. B.} } @misc{carbonell_desimone_henon, title={Compositions for protecting civil infrastructure}, volume={6,736,996}, number={2004 May 18}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Carbonell, R. G. and DeSimone, J. M. and Henon, F. E.} } @article{charpentier_desimone_roberts, title={Continuous polymerizations in supercritical carbon dioxide}, volume={819}, journal={Clean solvents: Alternative media for chemical reactions and processing}, publisher={Washington, DC: American Chemical Society; New York: Distributed by Oxford University Press}, author={Charpentier, P. A. and Desimone, J. M. and Roberts, G. W.}, editor={M. A. Abraham, L. MoensEditor}, pages={113–135} } @misc{charpentier_desimone_roberts, title={Continuous process for making polymers in carbon dioxide}, volume={6,914,105}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Charpentier, P. A. and DeSimone, J. M. and Roberts, G. W.} } @misc{williams_glenn_smith_holbrook_desimone, title={Endoprostheses and methods of manufacture}, volume={6,887,266}, number={2005 May 3}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Williams, M. S. and Glenn, R. A. and Smith, J. A. and Holbrook, K. D. and DeSimone, J. M.} } @misc{williams_glenn_smith_holbrook_desimone, title={Endoprostheses and methods of manufacture}, volume={7,163,554}, number={2007 Jan. 16}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Williams, M. S. and Glenn, R. A. and Smith, J. A. and Holbrook, K. D. and DeSimone, J. M.} } @misc{desimone_carson_miller_wells, title={Fluorinated copolymer surfactants and use thereof in aerosol compositions}, volume={6,451,287}, number={2002 Sep. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Carson, T. J. and Miller, J. F. and Wells, S.} } @book{joseph m. desimone, title={Green chemistry using liquid and supercritical carbon dioxide}, publisher={New York: Oxford University Press}, author={Joseph M. DeSimone, William Tumas} } @misc{desimone_maury_combes_menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,382,623}, number={1995 Jan. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_maury_combes_menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,451,633}, number={1995 Sep. 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_maury_combes_menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,506,317}, number={1996 Apr. 9}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_maury_combes_menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,589,105}, number={1996 Dec. 31}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_maury_j. r._menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,679,737}, number={1997 Oct. 21}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. Combes and J. R. and Menceloglu, Y. A.} } @misc{desimone_maury_combes_menceloglu, title={Heterogeneous polymerization in carbon dioxide}, volume={5,312,882}, number={1994 May 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_romack_canelas_shaffer, title={Heterogeneous polymerizations in carbon dioxide}, volume={5,780,553}, number={1998 Jul. 14}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. J. and Canelas, D. A. and Shaffer, K. A.} } @misc{desimone_maury_combes_menceloglu, title={Heterogenous polymerization in carbon dioxide}, volume={5,639,836}, number={1997 Jun. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maury, E. E. and Combes, J. R. and Menceloglu, Y. Z.} } @misc{desimone_williams, title={Intraluminal prostheses having polymeric material with selectively modified crystallinity and methods of making same}, volume={6,932,930}, number={2005 Aug. 23}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Williams, M. S.} } @misc{barborak_brookhart_desimone, title={Late transition metal catalysts for the CO- and terpolymerization of olefin and alkyne monomers with carbon monoxide}, volume={5,561,216}, number={1996 Oct. 1}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Barborak, J. C. and Brookhart, M. S. and DeSimone, J. M.} } @misc{desimone_deyoung_mcclain, title={Method and apparatus for cleaning substrates using liquid carbon dioxide}, volume={6,763,840}, number={2004 Jul. 20}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and DeYoung, J. P. and McClain, J. B.} } @misc{desimone_romack, title={Method for olefin oxidation}, volume={5,872,157}, number={1999 Feb. 16}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. J.} } @misc{deyoung_mcclain_desimone_romack, title={Method of dyeing substrates in carbon dioxide}, volume={6,010,542}, number={2000 Jan. 4}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeYoung, J. P. and McClain, J. B. and DeSimone, J. M. and Romack, T. J.} } @misc{desimone_romack_betts_mcclain, title={Method of entraining solid particulates in carbon dioxide fluids}, volume={6,224,774}, number={2001 May 1}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T. and Betts, D. E. and McClain, J. B.} } @misc{desimone_hunt, title={Method of making fluorinated copolymers}, volume={5,360,869}, number={1994 Nov. 1}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Hunt, M. O.} } @misc{desimone, title={Method of making fluoropolymers}, volume={5,496,901}, number={1996 Mar. 5}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{desimone, title={Method of making fluoropolymers}, volume={5,688,879}, number={1997 Nov. 18}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{desimone, title={Method of making fluoropolymers}, volume={5,739,223}, number={1998 Apr. 14}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{desimone, title={Method of making fluoropolymers}, volume={5,863,612}, number={1999 Jan. 26}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{desimone, title={Method of making fluoropolymers}, volume={5,922,833}, number={1999 Jul. 13}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{mcclain_romack_deyoung_lienhart_desimone_huggins, title={Methods for carbon dioxide dry cleaning with integrated distribution}, volume={6,332,342}, number={2001 Dec. 25}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={McClain, J. B. and Romack, T. J. and DeYoung, J. P. and Lienhart, R. B. and DeSimone, J. M. and Huggins, K. L.} } @misc{mcclain_romack_deyoung_lienhart_desimone_huggins, title={Methods for carbon dioxide dry cleaning with integrated distribution}, volume={6,248,136}, number={2001 Jun. 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={McClain, J. B. and Romack, T. J. and DeYoung, J. P. and Lienhart, R. B. and DeSimone, J. M. and Huggins, K. L.} } @misc{deyoung_mcclain_gross_simone, title={Methods for cleaning microelectronic structures with aqueous carbon dioxide systems}, volume={6,641,678}, number={2003 Nov. 4}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeYoung, J. P. and McClain, J. B. and Gross, S. M. and Simone, J. M.} } @misc{desimone_maier, title={Methods for solid state polymerizing polyesters utilizing carbon dioxide}, volume={6,107,443}, number={2000 Aug. 22}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maier, G.} } @misc{royer_desimone_roberts_khan, title={Methods of CO2-assisted reactive extrusion}, volume={6,900,267}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Royer, J. and DeSimone, J. M. and Roberts, G. W. and Khan, S. A.} } @misc{desimone_paisner, title={Methods of forming polymeric structures using carbon dioxide and polymeric structures formed therapy}, volume={6,765,030}, number={2004 Jul. 20}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Paisner, S. N.} } @misc{mcclain_desimone, title={Methods, apparatus and slurries for chemical mechanical planarization}, volume={6,623,355}, number={2003 Sep. 23}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={McClain, J. B. and DeSimone, J. M.} } @misc{mcclain_desimone, title={Methods, apparatus and slurries for chemical mechanical planarization}, volume={6,743,078}, number={2004 Jun. 1}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={McClain, J. B. and DeSimone, J. M.} } @misc{desimone_romack, title={Multi-phase polymerization process}, volume={5,527,865}, number={1996 Jun. 18}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Multi-phase polymerization process}, volume={5,514,759}, number={1996 May 7}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Multi-phase polymerization process}, volume={5,672,667}, number={1997 Sep. 30}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Multi-phase polymerization process}, volume={5,824,726}, number={1998 Oct. 20}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Multi-phase polymerization process}, volume={5,530,077}, number={1996 Jun. 25}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Nonaqueous polymerization of fluoromonomers}, volume={5,618,894}, number={1997 Apr. 8}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Nonaqueous polymerization of fluoromonomers}, volume={5,939,501}, number={1999 Aug. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Nonaqueous polymerization of fluoromonomers}, volume={5,674,957}, number={1997 Oct. 7}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Nonaqueous polymerization of fluoromonomers}, volume={5,981,673}, number={1999 Nov. 9}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_romack, title={Nonaqueous polymerization of fluoromonomers}, volume={5,939,502}, number={1999 Aug. 17}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Romack, T.} } @misc{desimone_mistele, title={Olefin metathesis reactions in carbon dioxide medium}, volume={5,840,820}, number={1998 Nov. 24}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Mistele, C. D.} } @article{khodabandehlou_tian_luft_khan_desimone, title={Particles for local delivery of proteins using intra-articular route}, volume={5}, number={6}, journal={Advanced Healthcare Materials}, author={Khodabandehlou, K. and Tian, S. M. and Luft, J. C. and Khan, S. A. and DeSimone, J. M.}, pages={653–658} } @misc{desimone_keiper, title={Phosphate fluorosurfactants for use in carbon dioxide}, volume={7,122,060}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Keiper, J. S.} } @misc{williams_holbrook_glenn_smith_desimone, title={Photocurable endoprosthesis system}, volume={7,141,061}, number={2006 Nov. 28}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Williams, M. S. and Holbrook, K. D. and Glenn, R. A. and Smith, J. A. and DeSimone, J. M.} } @article{royer_gay_adam_desimone_khan, title={Polymer melt rheology with high-pressure co2 using a novel magnetically levitated sphere rheometer}, volume={43}, number={8}, journal={Polymer}, author={Royer, J. R. and Gay, Y. J. and Adam, M. and DeSimone, J. M. and Khan, S. A.}, pages={2375–2383} } @misc{desimone_tumas_powell_mccleskey_romack_mcclain_birnbaum, title={Polymers for metal extractions in carbon dioxide}, volume={6,176,895}, number={2001 Jan. 23}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Tumas, W. and Powell, K. R. and McCleskey, T. M. and Romack, T. J. and McClain, J. B. and Birnbaum, E. R.} } @misc{desimone, title={Positive tone lithography with carbon dioxide development systems}, volume={6,929,904}, number={2005 Aug. 16}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M.} } @misc{desimone_maier, title={Process for the preparation of polyester in carbon dioxide}, volume={5,945,477}, number={1999 Aug. 31}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maier, G.} } @misc{desimone_maier, title={Process for the preparation of polyesters in carbon dioxide}, volume={5,977,292}, number={1999 Nov. 2}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Maier, G.} } @article{khodabandehlou_kumbhar_habibi_pandya_luft_khan_desimone, title={Silylated precision particles for controlled release of proteins}, volume={7}, number={10}, journal={ACS Applied Materials & Interfaces}, author={Khodabandehlou, K. and Kumbhar, A. S. and Habibi, S. and Pandya, A. A. and Luft, J. C. and Khan, S. A. and DeSimone, J. M.}, pages={5756–5767} } @misc{desimone_y., title={Synthesis of conductive polymers in liquid and supercritical CO.sub.2}, volume={5,855,819}, number={1999 Jan. 5}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Y., Ni} } @misc{desimone_givens_jikei_cohen, title={Synthesis of polycarbonates using Co2}, volume={6,288,202}, number={2001 Sep. 11}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Givens, R. and Jikei, M. and Cohen, J. D.} } @article{desimone, title={The role of diversity in commercializing basic science}, volume={57}, number={6}, journal={Research Technology Management}, author={DeSimone, J. M.}, pages={16–20} } @misc{samulski_desimone, title={Thiophene-based polymers}, volume={5,266,677}, number={1993 Nov. 30}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Samulski, E. T. and DeSimone, J. M.} } @misc{samulski_desimone, title={Thiophene-based polymers}, volume={5,354,836}, number={1994 Oct. 11}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Samulski, E. T. and DeSimone, J. M.} } @misc{desimone_samulski_archibald_sheares, title={Thiophene-containing poly(arylene ether) sulfones}, volume={5,410,013}, number={1995 Apr. 25}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Samulski, E. T. and Archibald, R. S. and Sheares, V. V.} } @misc{desimone_gulari_manke, title={Use of CO.sub.2 -soluble materials in making molds}, volume={5,860,467}, number={1999 Jan. 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Gulari, E. and Manke, C.} } @misc{desimone_gulari_manke, title={Use of CO2-soluble materials as transient coatings}, volume={6,298,902}, number={2001 Oct. 9}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={DeSimone, J. M. and Gulari, E. and Manke, C.} }