The thermal degradation of polysiloxanes—I. Poly(dimethylsiloxane)

摘要: Abstract Evolution of volatile materials from pure poly(dimethylsiloxane) heated under temperature programmed conditions (10° min−1 vacuum) is detectable at 343° and reaches a maximum 443°. The products comprise continuous mixture cyclic oligomers trimer upwards. Replacement the terminal hydroxyl by trimethyl silyl structures (end-blocking) results in considerable increase stability but no change distribution products. reaction strongly accelerated KOH methane then appears as significant product. Thermal gravimetry molecular weight measurements confirm that terminated polymer degrades stepwise fashion chain ends. These observations are discussed mechanistic point view. oxygen cross-linking occurs.