POLYOLEFIN RESIN COMPOSITION AND MARBLE GRAIN BUILDING MATERIAL MADE THEREFROM

摘要

PROBLEM TO BE SOLVED: To obtain a resin composition which can give marble grain moldings excellent in surface appearance, impact resistance, molding shrinkage and flexibility by mixing a polyolefin resin containing a polypropylene and an ethylene/ propylene copolymer rubber with a coloring pigment and a pattern-forming powder. SOLUTION: One hundred pts.wt. polyolefin resin containing 50-90 wt.% polypropylene and 10-50 wt.% ethylene/propylene copolymer rubber is mixed with 0.3-1.0 pt.wt. pattern-forming powder and a coloring pigment to obtain an injection molding resin composition. The polypropylene used is desirably an ethylene/propylene copolymer, and the ethylene/propylene copolymer rubber used is desirably one having an ethylene/propylene weight ratio of 40/60 to 90/10 and may be an ethylene/propylene/diene copolymer containing a copolymerized nonconjugated diene. The pattern-forming powder is desirably a thermosetting resin powder or a ceramic powder having a mean particle diameter of 50-2,000μm.