K. Chakrabarty et al., CHARACTERIZATION OF IONOMER SOLUTIONS - 2 - DYNAMIC LIGHT-SCATTERING-STUDIES ON SULFONATED POLYSTYRENE IONOMERS IN A NONPOLAR SOLVENT, Macromolecules, 31(21), 1998, pp. 7390-7397
The microphase behavior of lightly sulfonated polystyrene solutions in
Decalin was investigated using dynamic light scattering. The nature o
f the aggregates formed in these solutions by the association of the s
ulfonic acid groups was dependent on the temperature and concentration
. At high concentrations, aggregates persisted to temperatures far abo
ve the cloud point temperatures. At low concentrations, the aggregates
were absent except near the cloud point temperatures. The aggregation
increased as one approached the cloud point, thereby indicating that
the extensive aggregation provides the driving force for phase separat
ion in these solutions at temperatures higher than that for the precur
sor polystyrene solutions.