abstract |
Compositions stabilized by dioxopiperazinyl derivatives. Compositions of polyoxymethylene, mixtures of polycarbonate with acrylonitrile-butadiene-styrene terpolymer, and coatings based on acrylate functional resin and a crosslinking agent, are stabilized with the addition of a compound of formula I, where S has a value in the range from 1 to 8; R {sub, 1}, R {sub, 2}, R {sub, 3} and R {sub, 4}, independently of each other, are C {sub, 1} -C {sub, 4} alkyl, or R {sub, 1} and R {sub, 2} or R {sub, 3} and R {sub, 4}, together with the carbon atom to which they are attached, form a cyclopentyl or cyclohexyl ring; R {sub, 5} is hydrogen or other radicals described in claim 1; and A is as also described in claim 1. Compositions stabilized with compounds of formula I show good resistance against the damaging effects of light, oxygen and heat. |