Molecular and supramolecular structure of sulfonated polystyrene ionomers in solutions

The structure of sulfonated polystyrene ionomers in chloroform was studied by molecular hydrodynamics and neutron scattering methods. The ionomer containing 1.35 mol % of ionogenic SO₃Na groups undergoes the coil-globule transition and transforms to a micellar structure due to attraction of polar groups concentrated in the core surrounded by nonpolar chain fragments. At a sulfonation degree of 2.6 mol %, selfassembly of SO₃Na groups with adjacent chain segments to the structure such as a spherical layer, i.e., vesicle (hollow micelle with solvent) with boundaries formed by nonpolar chain fragments, is observed. Vesicular structures in solution associate in pairs. Intra- and interchain associations are significantly enhanced by hydrogen bonds in ionomers with acid groups SO₃H (2.6 and 4.47 mol %) which stabilize micellar structures, promoting their assembly into chain clusters and fragments of the simple cubic lattice.