METHOD FOR PRODUCING POLYOXYMETHYLENE RESIN COMPOSITION

摘要

Provided is a polyoxymethylene resin composition from which formaldehyde is generated in a sufficiently reduced amount upon molding, without carrying out a stabilization treatment for stabilizing an unstable terminal group in a crude oxymethylene copolymer. In the present invention, a hindered phenol-type antioxidant agent and an ethylene-(methacrylic acid) copolymer resin or an ethylene-(acrylic acid) copolymer resin or a salt thereof are melted and kneaded together to produce a polyoxymethylene resin composition without carrying out a stabilization treatment for stabilizing an unstable terminal group in a crude oxymethylene copolymer for which a polymerization catalyst is deactivated after the completion of copolymerization and in which the unstable terminal group is not stabilized yet. When the polyoxymethylene resin composition is extrusion-molded, the discoloration of a molded product or the deterioration in properties of the molded product can be prevented for a long period. Therefore, the polyoxymethylene resin composition produced in the present invention is suitable for forming an extrusion-molded article.