Microphase Behavior of Hydrogen Bonded Polystyrenesulfonate Ionomers From Dynamic Light Scattering Measurements
Dynamic light scattering was used to investigate the phase diagram of a lightly sulfonated (< 2been previously characterized and the phase boundary obtained by cloudpoint measurements. The hydrogen bonding of the sulfonate groups is considered to be the driving force behind intermolecular aggregation that leads to phase separation at the cloupoint. Dynamic light scattering measurements exhibited multiple relaxation times at temperatures somewhat above the cloudpoints. The longer relaxation times correspond to multichain aggregates. Parallel measurements of the parent polystyrene provided a measure of chain expansion and a means of accounting for changing solvent quality for the chain backbone.