PROCESS FOR PRODUCING THERMALLY STABLE POLYOXYMETHYLENE COPOLYMERS AND THEIR USE

摘要

A process for producing a polyoxymethylene copolymer by copolymerizing trioxane as a main monomer with a cyclic ether or a cyclic formal as a comonomer by using a cationically active catalyst, wherein an alkali metal fluoride is contacted with the copolymer after the completion of the copolymerization to thereby deactivate the polymerization catalyst. The treatment is effected at a pH-value of >/= 7.0, producing a polyoxymethylene copolymer having an improved heat stability.___________________________________________