@article{mineart_tallury_li_lee_spontak_2016, title={Phase-Change Thermoplastic Elastomer Blends for Tunable Shape Memory by Physical Design}, volume={55}, ISSN={["0888-5885"]}, DOI={10.1021/acs.iecr.6b04039}, abstractNote={Intelligent polymeric materials are of increasing interest in contemporary technologies due to their low cost, light weight, facile processability, and inherent ability to change properties, shape, and/or size upon exposure to an external stimulus. In this study, we consider thermally programmable shape-memory polymers (SMPs), which typically rely on chemistry-specific macromolecules composed of two functional species. An elastic, network-forming component permits stretched polymer chains to return to their relaxed state, and a switching component affords at least one thermal transition to regulate fixation of a desired strain state and return to a previous strain state. Here, we produce designer shape-memory materials by combining thermoplastic elastomeric triblock copolymers with a midblock-selective phase-change additive, thereby yielding shape-memory polymer blends (SMPBs). These materials not only exhibit tunable switch points but also controllable recovery kinetics. We further highlight the versatil...}, number={49}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Mineart, Kenneth P. and Tallury, Syamal S. and Li, Tao and Lee, Byeongdu and Spontak, Richard J.}, year={2016}, month={Dec}, pages={12590–12597} }
 @article{tallury_pourdeyhimi_pasquinelli_spontak_2016, title={Physical Microfabrication of Shape-Memory Polymer Systems via Bicomponent Fiber Spinning}, volume={37}, ISSN={["1521-3927"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84990927878&partnerID=MN8TOARS}, DOI={10.1002/marc.201600235}, abstractNote={As emerging technologies continue to require diverse materials capable of exhibiting tunable stimuli‐responsiveness, shape‐memory materials are of considerable significance because they can change size and/or shape in controllable fashion upon environmental stimulation. Of particular interest, shape‐memory polymers (SMPs) have secured a central role in the ongoing development of relatively lightweight and remotely deployable devices that can be further designed with specific surface properties. In the case of thermally‐activated SMPs, two functional chemical species must be present to provide (i) an elastic network capable of restoring the SMP to a previous strain state and (ii) switching elements that either lock‐in or release a temporary strain at a well‐defined thermal transition. While these species are chemically combined into a single macromolecule in most commercially available SMPs, this work establishes that, even though they are physically separated across one or more polymer/polymer interfaces, their shape‐memory properties are retained in melt‐spun bicomponent fibers. In the present study, we investigate the effects of fiber composition and cross‐sectional geometry on both conventional and cold‐draw shape memory, and report surprisingly high levels of strain fixity and recovery that generally improve upon strain cycling.
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}, number={22}, journal={MACROMOLECULAR RAPID COMMUNICATIONS}, publisher={Wiley-Blackwell}, author={Tallury, Syamal S. and Pourdeyhimi, Behnam and Pasquinelli, Melissa A. and Spontak, Richard J.}, year={2016}, month={Nov}, pages={1837–1843} }
 @article{tallury_mineart_woloszczuk_williams_thompson_pasquinelli_banaszak_spontak_2014, title={Communication: Molecular-level insights into asymmetric triblock copolymers: Network and phase development}, volume={141}, ISSN={["1089-7690"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84907545888&partnerID=MN8TOARS}, DOI={10.1063/1.4896612}, abstractNote={Molecularly asymmetric triblock copolymers progressively grown from a parent diblock copolymer can be used to elucidate the phase and property transformation from diblock to network-forming triblock copolymer. In this study, we use several theoretical formalisms and simulation methods to examine the molecular-level characteristics accompanying this transformation, and show that reported macroscopic-level transitions correspond to the onset of an equilibrium network. Midblock conformational fractions and copolymer morphologies are provided as functions of copolymer composition and temperature.}, number={12}, journal={JOURNAL OF CHEMICAL PHYSICS}, publisher={AIP Publishing}, author={Tallury, Syamal S. and Mineart, Kenneth P. and Woloszczuk, Sebastian and Williams, David N. and Thompson, Russell B. and Pasquinelli, Melissa A. and Banaszak, Michal and Spontak, Richard J.}, year={2014}, month={Sep} }
 @article{tallury_mineart_woloszczuk_williams_thompson_pasquinelli_banaszak_spontak_2014, title={Communication: Molecular-level insights into asymmetric triblock copolymers: Network and phase development (vol 141, 121103, 2014)}, volume={141}, ISSN={["1089-7690"]}, url={https://doi.org/10.1063/1.4898353}, DOI={10.1063/1.4898353}, abstractNote={First Page}, number={16}, journal={JOURNAL OF CHEMICAL PHYSICS}, publisher={AIP Publishing}, author={Tallury, Syamal S. and Mineart, Kenneth P. and Woloszczuk, Sebastian and Williams, David N. and Thompson, Russell B. and Pasquinelli, Melissa A. and Banaszak, Michal and Spontak, Richard J.}, year={2014}, month={Oct} }
 @article{tallury_spontak_pasquinelli_2014, title={Dissipative particle dynamics of triblock copolymer melts: A midblock conformational study at moderate segregation}, volume={141}, ISSN={["1089-7690"]}, url={https://doi.org/10.1063/1.4904388}, DOI={10.1063/1.4904388}, abstractNote={As thermoplastic elastomers, triblock copolymers constitute an immensely important class of shape-memory soft materials due to their unique ability to form molecular networks stabilized by physical, rather than chemical, cross-links. The extent to which such networks develop in triblock and higher-order multiblock copolymers is sensitive to the formation of midblock bridges, which serve to connect neighboring microdomains. In addition to bridges, copolymer molecules can likewise form loops and dangling ends upon microphase separation or they can remain unsegregated. While prior theoretical and simulation studies have elucidated the midblock bridging fraction in triblock copolymer melts, most have only considered strongly segregated systems wherein dangling ends and unsegregated chains become relatively insignificant. In this study, simulations based on dissipative particle dynamics are performed to examine the self-assembly and networkability of moderately segregated triblock copolymers. Utilizing a density-based cluster-recognition algorithm, we demonstrate how the simulations can be analyzed to extract information about microdomain formation and permit explicit quantitation of the midblock bridging, looping, dangling, and unsegregated fractions for linear triblock copolymers varying in chain length, molecular composition, and segregation level. We show that midblock conformations can be sensitive to variations in chain length, molecular composition, and bead repulsion, and that a systematic investigation can be used to identify the onset of strong segregation where the presence of dangling and unsegregated fractions are minimal. In addition, because this clustering approach is robust, it can be used with any particle-based simulation method to quantify network formation of different morphologies for a wide range of triblock and higher-order multiblock copolymer systems.}, number={24}, journal={JOURNAL OF CHEMICAL PHYSICS}, publisher={AIP Publishing}, author={Tallury, Syamal S. and Spontak, Richard J. and Pasquinelli, Melissa A.}, year={2014}, month={Dec} }
 @article{jiang_tallury_qiu_pasquinelli_2014, title={Molecular dynamics simulations of the effect of the volume fraction on unidirectional polyimide-carbon nanotube nanocomposites}, volume={67}, ISSN={["1873-3891"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84892781848&partnerID=MN8TOARS}, DOI={10.1016/j.carbon.2013.10.016}, abstractNote={Molecular dynamics (MD) simulations were used to predict the effect of the reinforcement volume fraction on a unidirectional nanocomposite comprised of a polyimide and multi-walled carbon nanotubes (MWCNTs). We derived a modified volume fraction equation that takes the interface into account, and thus can precisely calculate the volume fraction of the reinforcement. From the MD simulations, both the stress and the modulus are predicted to increase with increasing number of MWCNTs as a function of a constantly applied strain, although some interesting observations were made in comparison to a pure polyimide system that is ordered, akin to the pre-nucleated crystalline system. In addition, we developed an approach to indirectly predict the change in the degree of order in the matrix with the addition of the CNT reinforcements. The results suggest that the degree of ordering increases with an increase in the volume fraction of MWCNTs, especially at the polymer–CNT interface according to number density plots of the polymer, which is consistent with the hypothesis that CNTs can act as nucleation sites for the crystallization of the polymer matrix.}, journal={CARBON}, publisher={Elsevier BV}, author={Jiang, Qian and Tallury, Syamal S. and Qiu, Yiping and Pasquinelli, Melissa A.}, year={2014}, month={Feb}, pages={440–448} }
 @article{tallury_smyth_cakmak_pasquinelli_2012, title={Molecular dynamics simulations of interactions between polyanilines in their inclusion complexes with β-cyclodextrins}, volume={116}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84857387776&partnerID=MN8TOARS}, DOI={10.1021/jp206745q}, abstractNote={Conductive polymers have several applications such as in flexible displays, solar cells, and biomedical sensors. An inclusion complex of a conductive polymer and cyclodextrin is desired for some applications such as for molecular wires. In this study, different orientations of β-cyclodextrin rings on a single polyaniline (PANI) chain in an alternating emeraldine form were simulated using molecular dynamics. The simulations were performed in an implicit solvent environment that corresponds to experimental conditions. When the larger opening of the β-cyclodextrin toroids face the same direction, the cyclodextrins tend to repel each other. Alternating the orientation of the β-cyclodextrins on the chain causes the β-cyclodextrin rings to be more attractive to one another and form pairs or stacks of rings. These simulations explain how the β-cyclodextrins can be used to shield the polyaniline from outside chemical action by analyzing the PANI/cyclodextrin interactions from a molecular perspective.}, number={7}, journal={Journal of Physical Chemistry B}, publisher={American Chemical Society}, author={Tallury, Syamal S. and Smyth, Margaret B. and Cakmak, Enes and Pasquinelli, Melissa A.}, year={2012}, pages={2023–2030} }
 @article{tallury_pasquinelli_2010, title={Molecular Dynamics Simulations of Flexible Polymer Chains Wrapping Single-Walled Carbon Nanotubes}, volume={114}, ISSN={["1520-6106"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77950266139&partnerID=MN8TOARS}, DOI={10.1021/jp908001d}, abstractNote={The goal of this study is to explore the interface between single-walled carbon nanotubes (SWCNTs) and polymer chains with flexible backbones in vacuo via molecular dynamics (MD) simulations. These simulations investigate whether the polymers prefer to wrap the SWCNT, what the molecular details of that interface are, and how the interfacial interaction is affected by the chemical composition and structure of the polymer. The simulations indicate that polymers with flexible backbones tend to wrap around the SWCNT, although not in any distinct conformation; no helical conformations were observed. PAN with the cyano side group showed a preference for transversing the length of the SWCNT rather than wrapping around its diameter, and the cyano group prefers to align parallel to the SWCNT surface. Flexible backbone polymers with bulky and aromatic side groups such as PS and PMMA prefer intrachain coiling rather than wrapping the SWCNT. Moment of inertia plots as a function of time quantify the interplay between intrachain coiling and adsorption to the SWCNT surface.}, number={12}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, publisher={ACS Publications}, author={Tallury, Syamal S. and Pasquinelli, Melissa A.}, year={2010}, month={Apr}, pages={4122–4129} }
 @article{tallury_pasquinelli_2010, title={Molecular Dynamics Simulations of Polymers with Stiff Backbones Interacting with Single-Walled Carbon Nanotubes}, volume={114}, ISSN={["1520-5207"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77954898628&partnerID=MN8TOARS}, DOI={10.1021/jp101191j}, abstractNote={The goal of this study is to explore the interface between single-walled carbon nanotubes (SWCNTs) and polymer chains with semiflexible and stiff backbones in vacuum via molecular dynamics (MD) simulations, which complements our previous work with flexible backbone polymers. These simulations investigate the structural and dynamical features of interactions with the SWCNT, such as how the polymers prefer to interface with the SWCNT and how the interfacial interaction is affected by the chemical composition and structure of the polymer. The simulations indicate that polymers with stiff and semiflexible backbones tend to wrap around the SWCNT with more distinct conformations than those with flexible backbones. Aromatic moieties along the backbone appear to dictate the adsorption conformation, which is likely due to the preference for optimizing pi-pi interactions, although the presence of bulky aliphatic side chains can hinder those interactions. Moment of inertia plots as a function of time indicate that the adsorption of polymers with stiff backbones tends to be a two-step process, in contrast to flexible backbones.}, number={29}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, publisher={American Chemical Society}, author={Tallury, Syamal S. and Pasquinelli, Melissa A.}, year={2010}, month={Jul}, pages={9349–9355} }