METHOD FOR PRODUCING POLYOXYMETHYLENE RESIN COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a polyoxymethylene resin composition which is sufficiently suppressed in the amount of formaldehyde generation during molding without performing stabilizing processing to stabilize unstable terminal groups of a crude oxymethylene copolymer.SOLUTION: There is produced a polyoxymethylene resin composition by melt-kneading a hindered phenolic antioxidant and an ethylene-methacrylic acid copolymer resin or an ethylene-acrylic acid copolymer resin or a salt thereof without subjecting a crude oxymethylene copolymer having unstable terminal groups to stabilizing processing to stabilize the unstable terminal groups though a polymerization catalyst is inactivated after the copolymerization. Since the long-term discoloration and the long-term deterioration of physical properties can be suppressed even after extrusion molding the polyoxymethylene resin composition, the resulting polyoxymethylene resin composition is suitable for molding an extrusion molded article.