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 styrenesulfonic acid has been studied using thermogravimetric analysis, TGA/FTIR, and cone calorimetry. The blends have enhanced thermal stability relative to virgin polystyrene but there is no enhancement in thermal stability for the copolymers. Apparently, it is necessary to have adjacent sulfonic acid groups in order to permit the formation of a graphite-like char which can provide 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 significantly enhanced thermal stability

How does Cross-Linking Effect the Thermal Stability of Polyisoprene

Polyisoprene can be cross-linked by an initial lithiation followed by reaction with both monochloro compounds and dichloro compounds. The monochloro compounds effect crosslinking through a lithium-chlorine exchange route while the use of dichloro compounds links the PIP chains with the spacer between the two chlorine atoms. A significant amount of char is produced from compounds which have been cross-linked with aromatic dihalides while aliphatic dihalides do not produce significant char