Influence of a surfactant additive on the crystallization of syndiotactic polystyrene and sulfonated syndiotactic polystyrene.

Syndiotactic polystyrene (sPS) was mixed with dodecylbenzene sodium sulfonate (DBSNa), benzene sodium sulfonate (BSNa) and dodecylbenzene (DB), to investigate the influence of these additives on the crystallization behavior of sPS. The crystallization of sPS containing DBSNa was significantly slower than that of sPS containing DB or BSNa. Since SAXS investigations indicated the presence of DBSNa aggregates within sPS/DBSNa samples, the observed decrease in the rate of crystallization is attributed to a slow expulsion of the bulky DBSNa aggregates from the crystalline growth front. In comparison, sulfonated syndiotactic polystyrene (SsPS)/DBSNa mixtures crystallized faster than SsPS, due to a disruption of the electrostatic crosslinks by DBSNa.