Effect of Ionic Liquids on the Conformation of Ionizable Polymers from a Single Molecule to an Assembly

Ionizable polymers have been incorporated successfully into light weigh energy applications. However, the mobility of ions, critical to the function these polymers is rather low. To overcome this issue, highly mobile salts have been added, among them are ionic liquids. Though salts enhance mobility, they interact with the polymers, affecting their structure and dynamics. Here we probe the effects of a model ionic liquid family, 1-alkyl 3-methylimidazolium bis (trifluoromethyl sulfonyl) imide), on the conformation of polystyrene sulfonate (PSS) in the ionomers and the polyelectrolyte regimes, using molecular dynamics simulations. Starting with single PSS molecules, with sulfonation fraction f ranging from 0 to 0.96, and building to more complex assemblies of multi-component polymers with containing a PSS block, the polymers were dissolved in the ionic liquids. Results for radius of gyration, the static and dynamic structure factors S(q) and S(q,t) of all components, the residence time as of each of the ions by the polymers will be discussed.