Stabilized polymer compositions

摘要

Compositions comprise an a -olefin copolymer as defined and a linear thiodialkanoate polyester of molecular weight 500 to 4000 and of formula or where n is 2 to 20, R2 is hydrogen or , R1 is an alkyl, alkenyl, cycloalkyl or aryl radical, R is a methylene, alkyl substituted methylene, oxydimethylene, thiodimethylene, cycloalkylene or arylene radical, x is 0 to 10 and y is 2 or 3. The olefin copolymer is (1) a copolymer of a mixture of C2- 22 a -monoolefins, (2) a copolymer of a C2- 22 a -monoolefin with a diolefin, (3) a copolymer of an a -monoolefin with an acrylate or styrene, or (4) a mixture of a poly-a -olefin with a polyamide, polyester or synthetic rubber. Specified a -olefins are ethylene, propylene, butene-1, dodecene-1, octadecene-1 and docosene-1. Many suitable polyester forming components are specified. The compositions of the invention preferably also comprise a conventional phenolic antioxidant, of which many examples are given. In examples, propylene/butene and propylene/isoprene copolymers are stabilized with polyesters derived from 3,31-thiodipropionic acid, ethylene glycol and stearic acid.