PRE-EXPANDED POLYPROPYLENE RESIN PARTICLE AND MOLDED OBJECT OBTAINED BY IN-MOLD EXPANSION

摘要

Pre-expanded polyolefin resin particles for in-mold expansion which readily attain satisfactory secondary expansibility and surface properties/dimensional properties even when a molding having a shape with a small wall thickness is to be obtained therefrom by in-mold expansion. The pre-expanded polypropylene resin particles are characterized by comprising as a base resin a polypropylene resin (X) obtained from a resin mixture of a polypropylene resin (A) having a melting point of 140°C or lower and a polypropylene resin (B) having a melting point of 145°C or higher by regulating the melt index of the mixture with an organic peroxide to 5-20 g/10 min, excluding 20 g/10 min.