Thermal degradation of blends of polystyrene and poly(sodium 4-styrenesulfonate) and the copolymer, poly(styrene-co-sodium 4-styrenesulfonate)

The thermal degradation of blends and copolymers of styrene with styrenesul fonic acid has been studied using thermogravimetric analysis, TGA/FTIR, and cone calorimetry. The blends have enhanced thermal stability relative to v irgin polystyrene but there is no enhancement in thermal stability for the copolymers. Apparently, it is necessary to have adjacent sulfonic acid grou ps in order to permit the formation of a graphite-like char which can provi de thermal protection to the polymer. It is necessary to have a good match in degradation temperatures of the two components if one is to have signifi cantly enhanced thermal stability. (C) 1999 Elsevier Science Ltd. All right s reserved.