Solvent Effects on the Structure of Sulfonated Polystyrene Networks

ORAL

Abstract

Driven by ionic association, ionomers form dynamic sparse networks in solutions at extremely low ionic content. Here we probe the factors that affect the structure of these types of networks formed by lightly sulfonated polystyrene (PSS) using small angle neutron scattering (SANS). Measurements were carried out in 0.25-10Wt% PSS in toluene/ethanol solutions, across a broad temperature range. In toluene, a good solvent for the PS, the SANS patterns consist of a broad signature at intermediate q, attributed here to an average network mesh size, determined by the distance between ionic physical crosslinks. At low q, a network characteristic upturn is observed. With increasing concentrations, the characteristic dimension, calculated from Rg of a Gaussian chain, decreases by ~1nm due to increasing cluster size and numbers. The long-range correlations of ~20nm, were captured by the Beacuge model. The PS chains assume an overall Gaussian configuration around the ionic clusters. Surprisingly, while the long-range correlations diminish with addition of ethanol, the mesh size decreases. While the ionic clusters become less defined, the PS chains are concurrently affected, assuming a more constrained chain configuration.

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Presenters

  • Chathurika Kosgallana

    Department of Chemistry, Clemson University, Clemson, SC, United States, Department of Chemistry, Clemson, SC, 29634, United States, Clemson University, Department of Chemistry, Clemson University, Clemson, SC, United States., Chemistry, Clemson University

Authors

  • Chathurika Kosgallana

    Department of Chemistry, Clemson University, Clemson, SC, United States, Department of Chemistry, Clemson, SC, 29634, United States, Clemson University, Department of Chemistry, Clemson University, Clemson, SC, United States., Chemistry, Clemson University

  • Sidath Wijesinghe

    Department of Chemistry, University Of North Carolina, Department of Chemistry, Clemson University, Clemson, SC, United States

  • Manjula Senanayake

    Department of Chemistry , Clemson University, Clemson, SC, United States,29634, Department of Chemistry, Clemson University, Clemson, SC, United States, Department of Chemistry, Clemson, SC, 29634, United States, Clemson University, Department of Chemistry, Clemson University, Clemson, SC, United States., Chemistry, Clemson University

  • Supun S. Mohottalalage

    Department of Chemistry, Clemson University, Clemson, SC, United States, Department of Chemistry, Clemson, SC, 29634, United States, Clemson University, Chemistry, Clemson University

  • Lilin He

    Oak Ridge National Laboratory, Oak Ridge, TN, United States, Oak Ridge National Laboratory

  • Dvora Perahia

    Department of Chemistry/Department of Physics, Clemson University, Clemson, SC, United States, 29634, Clemson University, Department of Chemistry/ Department of Physics, Clemson University, Clemson, SC, United States, Department of Chemistry, Clemson, SC, 29634, United States, Clemson University, Department of Physics, Clemson, SC, 29631, United States, Clemson University, Department of Chemistry/Department of Physics, Clemson University, Clemson, SC, United States., Chemistry, Physics, Clemson University