POLYPROPYLENE RESIN COMPOSITION WITH EXCELLENT COATING PROPERTY

摘要

PURPOSE: A polypropylene resin composition is provided, to enable the composition to be coated with a sufficient adhesive strength even by direct coating without using a primer and to improve the molding appearance, the impact resistance and the lightweightness. CONSTITUTION: The polypropylene resin composition comprises 60-80 wt% of crystalline polypropylene; 10-30 wt% of ethylene-propylene-based copolymer rubber; 3-10 wt% of polyolefin-graft-vinyl copolymer; and 1-5 wt% of azodicarbonamide-based foaming agent. Preferably the crystalline polypropylene has a melting index of 1-80 g/10 min (ASTM D1238, 230 deg.C); the ethylene-propylene-based copolymer rubber comprises ethylene and propylene in the ratio of 70:30 to 80:20 by weight, and has a Mooney viscosity of 10-100 (ML1+4, 100 deg.C) and a melting index of 0.5-25 g/10 min; and the polyolefin-graft-vinyl copolymer comprises polyolefin and vinyl copolymer in the ratio of 60:50 to 80;20 by weight and has a molecular weight of 5,000-8,000 and a graft ratio of 50 % or more.