Abstract: A method for stabilization of polymers susceptible to an oxidative destruction which comprises intermixing a polymer with formate of a multi-valent metal in an amount ranging from 0.1 to 20 parts by weight per 100 parts by weight of the polymer. The resulting mixture is subjected to a heat treatment at the temperature of decomposition of the selected formiate of variable-valency metal. The method enables the production of polymers and articles therefrom possessing high physico-mechanical properties. The method is versatile and applicable to any type of polymers susceptible to oxidative destruction.

Abstract: A method for stabilization of fluoro-organic copolymers of the ethylene series which comprises mixing said copolymer with xenon difluoride taken in an amount ranging from 0.1 to 15% by weight of the starting copolymer at a temperature not exceeding 20.degree. C.The method according to the present invention makes it possible to produce copolymers and articles therefrom having an increased thermal stability and longer service life as compared to those produced by the prior art methods. The method is versatile. It is applicable to any type of copolymer of the ethylene series containing bonds which are weaker than the C - F bond.