@article{spontak_ryan_2020, title={Polymer blend compatibilization by the addition of block copolymers}, ISBN={["978-0-12-816006-0"]}, DOI={10.1016/B978-0-12-816006-0.00003-7}, abstractNote={Since most polymer pairs are inherently thermodynamically incompatible, a wide variety of physical methods has been developed to reduce the interfacial tension in, and thus compatibilize, multicomponent polymer blends. In this chapter, we provide an overview of polymer/polymer phase behavior and elucidate the molecular factors responsible for phase separation. Several strategies introduced to compatibilize phase-separated polymer blends are briefly described, with an emphasis on block copolymers as macromolecular surfactants. The unique attributes of neat block copolymers are examined prior to discussing their ubiquitous use as compatibilizing agents in polymer blends. The criteria and conditions capable of promoting compatibilization are consequently identified, and a molecular-level description of the factors responsible for interfacial modification (and adhesion) is provided. In addition to conventional blends prepared by either high-shear melt/solid mixing or solution casting, we further consider compatibilization of blends with precisely controlled and modified interfaces. One example consists of bilayered polymer films that either contain or are separated by block copolymers differing in concentration and/or molecular composition/weight. Similarly, the effectiveness of adding a premade block copolymer to induce compatibilization in phase-modulated bicomponent fibers is also examined.}, journal={COMPATIBILIZATION OF POLYMER BLENDS: MICRO AND NANO SCALE PHASE MORPHOLOGIES, INTERPHASE CHARACTERIZATION, AND PROPERTIES}, author={Spontak, Richard J. and Ryan, Justin J.}, year={2020}, pages={57–102} }
 @article{dai_ansaloni_ryan_spontak_deng_2019, title={Incorporation of an ionic liquid into a midblock-sulfonated multiblock polymer for CO2 capture}, volume={588}, ISSN={["1873-3123"]}, DOI={10.1016/j.memsci.2019.117193}, abstractNote={In the present work, hybrid block ionomer/ionic liquid (IL) membranes containing up to 40 wt% IL are prepared by incorporating 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) into a midblock-sulfonated pentablock polymer (Nexar) that behaves as a thermoplastic elastomer. Various analytical techniques, including thermogravimetric analysis (TGA), Fourier-transform infrared (FTIR) spectroscopy, small-angle X-ray scattering (SAXS), and water sorption have been employed to characterize the resultant membrane materials. Single- and mixed-gas permeation tests have been performed at different relative humidity conditions to evaluate membrane gas-separation performance and interrogate the molecular transport of CO2 through these membranes. Addition of IL to Nexar systematically enhances CO2 permeability through membranes in the dry state. Introduction of water vapor into the gas feed further promotes CO2 transport, yielding a maximum permeability of 194 Barrers and a maximum CO2/N2 selectivity of 128 under different test conditions. These results confirm that humidified Nexar/IL hybrid membranes constitute promising candidates for the selective removal, and subsequent capture, of CO2 from mixed gas streams to reduce the environmental contamination largely responsible for global climate change.}, journal={JOURNAL OF MEMBRANE SCIENCE}, author={Dai, Zhongde and Ansaloni, Luca and Ryan, Justin J. and Spontak, Richard J. and Deng, Liyuan}, year={2019}, month={Oct} }
 @article{mineart_ryan_appavou_lee_gradzielski_spontak_2019, title={Self-Assembly of a Midblock-Sulfonated Pentablock Copolymer in Mixed Organic Solvents: A Combined SAXS and SANS Analysis}, volume={35}, ISSN={["0743-7463"]}, DOI={10.1021/acs.langmuir.8b03825}, abstractNote={Ionic, and specifically sulfonated, block copolymers are continually gaining interest in the soft materials community due to their unique suitability in various ion-exchange applications such as fuel cells, organic photovoltaics, and desalination membranes. One unresolved challenge inherent to these materials is solvent templating, that is, the translation of self-assembled solution structures into nonequilibrium solid film morphologies. Recently, the use of mixed polar/nonpolar organic solvents has been examined in an effort to elucidate and control the solution self-assembly of sulfonated block copolymers. The current study sheds new light on micellar assemblies (i.e., those with the sulfonated blocks comprising the micellar core) of a midblock-sulfonated pentablock copolymer in polar/nonpolar solvent mixtures by combining small-angle X-ray and small-angle neutron scattering. Our scattering data reveal that micelle size depends strongly on overall solvent composition: micelle cores and coronae grow as the fraction of nonpolar solvent is increased. Universal model fits further indicate that an unexpectedly high fraction of the micelle cores is occupied by polar solvent (60-80 vol %) and that partitioning of the polar solvent into micelle cores becomes more pronounced as its overall quantity decreases. This solvent presence in the micelle cores explains the simultaneous core/corona growth, which is otherwise counterintuitive. Our findings provide a potential pathway for the formation of solvent-templated films with more interconnected morphologies due to the greatly solvated micellar cores in solution, thereby enhancing the molecular, ion, and electron-transport properties of the resultant films.}, number={4}, journal={LANGMUIR}, author={Mineart, Kenneth P. and Ryan, Justin J. and Appavou, Marie-Sousai and Lee, Byeongdu and Gradzielski, Michael and Spontak, Richard J.}, year={2019}, month={Jan}, pages={1032–1039} }
 @article{ashraf_ryan_satkowski_smith_spontak_2018, title={Effect of Systematic Hydrogenation on the Phase Behavior and Nanostructural Dimensions of Block Copolymers}, volume={10}, ISSN={["1944-8252"]}, DOI={10.1021/acsami.7b19433}, abstractNote={Unsaturated polydienes are frequently hydrogenated to yield polyolefins that are more chemically stable. Here, the effects of partial hydrogenation on the phase behavior and nanostructure of polyisoprene-containing block copolymers are investigated. To ensure access to the order-disorder transition temperature (TODT) over a wide temperature range, we examine copolymers with at least one random block. Dynamic rheological and scattering measurements indicate that TODT increases linearly with increasing hydrogenation. Small-angle scattering reveals that the temperature-dependence of the Flory-Huggins parameter changes and the microdomain period increases, while the interfacial thickness decreases. The influence of hydrogenation becomes less pronounced in more constrained multiblock copolymers.}, number={4}, journal={ACS APPLIED MATERIALS & INTERFACES}, author={Ashraf, Arman R. and Ryan, Justin J. and Satkowski, Michael M. and Smith, Steven D. and Spontak, Richard J.}, year={2018}, month={Jan}, pages={3186–3190} }
 @article{dai_ansaloni_ryan_spontak_deng_2018, title={Nafion/IL hybrid membranes with tuned nanostructure for enhanced CO2 separation: effects of ionic liquid and water vapor}, volume={20}, ISSN={["1463-9270"]}, DOI={10.1039/c7gc03727a}, abstractNote={Fully hydrated hybrid membranes based on a polyelectrolyte mixed with an ionic liquid possess gas permeation properties of significant interest for CO2 capture applications.}, number={6}, journal={GREEN CHEMISTRY}, author={Dai, Zhongde and Ansaloni, Luca and Ryan, Justin J. and Spontak, Richard J. and Deng, Liyuan}, year={2018}, month={Mar}, pages={1391–1404} }
 @article{ryan_mineart_lee_spontak_2018, title={Ordering and Grain Growth in Charged Block Copolymer Bulk Films: A Comparison of Solvent-Related Processes}, volume={5}, ISSN={["2196-7350"]}, DOI={10.1002/admi.201701667}, abstractNote={Abstract}, number={8}, journal={ADVANCED MATERIALS INTERFACES}, author={Ryan, Justin J. and Mineart, Kenneth P. and Lee, Byeongdu and Spontak, Richard J.}, year={2018}, month={Apr} }