A method for stabilizing synthetic thermoplastic materials against thermal degradation

摘要

The present invention relates to a novel method for stabilizing synthetic thermoplastic materials against thermal degradation, which comprises incorporating in said materials one or more compounds of the formula (I) in which R₁ is unsubstituted or substituted phenyl, n is e.g. 1, 2 or 3, and, when n is 1, R₂ is e.g. -COR₃, - COOR₄ or -CO-N(R₅)R₆ in which R₃ is e.g. C₄-C₁₇alkyl, R₄ is e.g. C₄-C₁₈alky cyclohexyl or t-butylcyclohexyl, R₅ and R₆ which can be identical or different are e.g. C₂-C₈alkyl or cyclohexyl, and, when n is 2, R₂ is e.g. -CO-R₁₀-OC, -COO-R₁₁-OOC- or -CONH-R₁₂-NHCO- in which R₁₀ is e.g. C₂-C₈alkylene, R₁₁ is e.g. C₄-C₆alkylene and R₁₂ is e.g. C₄-C₆alkylene, and, when n is 3, R₂ is e.g. benzenetricarbonyl.;Several compounds of the formula (I) are new