title: Clustering effects in ionic polymers: Molecular dynamics simulations.
abstract: Ionic clusters control the structure, dynamics, and transport in soft matter. Incorporating a small fraction of ionizable groups in polymers substantially reduces the mobility of the macromolecules in melts. These ionic groups often associate into random clusters in melts, where the distribution and morphology of the clusters impact the transport in these materials. Here, using molecular dynamic simulations we demonstrate a clear correlation between cluster size and morphology with the polymer mobility in melts of sulfonated polystyrene. We show that in low dielectric media ladderlike clusters that are lower in energy compared with spherical assemblies are formed. Reducing the electrostatic interactions by enhancing the dielectric constant leads to morphological transformation from ladderlike clusters to globular assemblies. Decrease in electrostatic interaction significantly enhances the mobility of the polymer.
authors.affiliation: Department of Chemistry, Clemson University, Clemson, South Carolina 29634, USA.
authors.forename: Anupriya
authors.initials: A
authors.lastname: Agrawal
authors.affiliation: Department of Chemistry, Clemson University, Clemson, South Carolina 29634, USA.
authors.forename: Dvora
authors.initials: D
authors.lastname: Perahia
authors.affiliation: Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
authors.forename: Gary S
authors.initials: GS
authors.lastname: Grest