LIGHT-SCATTERING AND SMALL-ANGLE X-RAY-SCATTERING STUDIES OF AN IONOMER POLY(STYRENE-SODIUM 2-(ACRYLAMIDO)-2-METHYLPROPANESULFONATE) IN POLAR-SOLVENTS

Ionomers with very high levels of sulfonate content, poly(styrene-sodium 2(acrylamido)-2-methylpropanesulfonate) (poly(St-NaAMPS)), in polar solvents were investigated by using laser light scattering (LLS) and small-angle X-ray scattering (SAXS). The aggregation behavior in the dilute-solution regime could be further confirmed by laser light-scattering measurements of the apparent hydrodynamic radius as a function of temperature and concentration. An ionic peak of this polymer solution, as observed in the SAXS pattern, showed a strong concentration dependence but depended less on the sulfonate content. The SAXS pattern was compared with the core-shell model and the liquidlike structure model. A multifold structure of aggregates in poly(St-NaAMPS) solutions was suggested.