| abstract |
PROBLEM TO BE SOLVED: To provide a lightweight polypropylene foam composition which is excellent in heat resistance, oil resistance and impact resistance, hardly causes uneven wall thickness and thinning, a precursor thereof, and a foamed molded article. thing. SOLUTION: This is a foamed polypropylene composition obtained by foaming a propylene block copolymer component containing a copolymer of crystalline polypropylene and ethylene-propylene. The intrinsic viscosity [η] RC of the copolymer in the block copolymer component is 1.7 to 2.8 dl / g, and the intrinsic viscosity ratio [η] RC / [η] PP of this copolymer and the above-mentioned crystalline polypropylene is 0. In the range of 7 to 1.2, the intrinsic viscosity ratio [η] RC / [η] PP and their weight ratio W PP / W Product with RC ([η] RC / [η] PP ) × (W PP / W RC ) is in the range of 1.0 to 3.0. It is a foam molded article obtained by molding the above-mentioned foamed polypropylene-based composition. |