Process for producing foamed particles of propylene copolymer resin

摘要

A process for producing propylene random copolymer resin foamed particles is disclosed. The process comprises dispersing propylene-ethylene random copolymer resin particles having an ethylene content of from 1 to 12% by weight in water in a closed vessel, feeding an inorganic gas into the closed vessel to raise the pressure within the closed vessel to at least 5 Kg/cm2G, heating the dispersion to a temperature above the melting point of said copolymer resin particles but not higher than that by 25 DEG C. or more, opening a discharge port provided in the closed vessel below the water surface, and releasing the copolymer resin particles together with water as a dispersing medium into an atmosphere having a lower pressure than in the closed vessel. A foamed product produced by molding the foamed particles has firm bondage among the particles and excellent mechanical strength.