Halide-vinyl polymers, degradation

PVF is more thermally stable than other vinyl halide polymers. High molecular weight PVF is reported to degrade in an inert atmosphere, with concurrent HF loss and backbone cleavage occurring at about 450°C (71,72). In air, HF loss occurs at about 350°C, followed by backbone cleavage around 450°C. 

Polyisobutylene of low molecular weight was synthesized by a Wurtz type reaction from l,4-dibromo-2,2,3,3 tetramethylbutane. Polyacrylates were obtained from alternating copolymerization of symmetric internal olefins or ethylene with maleic anhydride followed by quantitative esterification. Poly(vinyl halides) were prepared from cis-1,4-polybutadiene by chlorination (H-H PVC) or bromin-ation (H-H PrBr). The polymers were characterized and their chemical, thermal, degradation solution, melt and blending behavior was studied. 

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