Patent ID: 9657165
Date: 2017-05-23
CPC Classifications: C08L

Claim:
1. A polypropylene resin composition comprising 95-98 wt % of a propylene-based material (A) defined below and 2-5 wt % of a propylene-ethylene random copolymer (B) defined below, where the combined amount of the propylene-based material (A) and the propylene-ethylene random copolymers (B) is taken as 100 wt %, the propylene-based material (A) being a material comprising 50-100 wt % of a propylene-based polymeric material (A-1) composed of a propylene homopolymer component (i) and a propylene-ethylene random copolymer component (ii) produced by multistage polymerization and 0-50 wt % of a propylene homopolymer (A-2), where the combined amount of the propylene-based polymeric material (A-1) and the propylene homopolymer (A-2) is taken as 100 wt %, the propylene-based polymeric material (A-1) satisfies requirements (1) and (2) defined below, and the content of the propylene-ethylene random copolymer component (ii) in the propylene-based material (A) is 5-35 wt %, requirement (1): the content of the propylene homopolymer component (i) in the propylene-based polymeric material (A-1) is chosen from the range of 55-90 wt % and the content of the propylene-ethylene random copolymer component (ii) is chosen from the range of 10-45 wt % (the sum total of the content of propylene polymer component (i) and the content of propylene-ethylene random copolymer component (ii) is taken as 100 wt %), requirement (2): the propylene-ethylene random copolymer component (ii) of the propylene-based polymeric material (A-1) comprises more than 40 wt % but not more than 80 wt % of monomer units derived from ethylene and not less than 20 wt % but less than 60 wt % of monomer units derived from propylene (the overall weight of the propylene-ethylene random copolymer component (ii) is taken as 100 wt %), the propylene-ethylene random copolymer (B) comprises 88-94 wt % of monomer units derived from propylene and 6-12 wt % of monomer units derived from ethylene, where the overall weight of the propylene-ethylene random copolymer component (B) is taken as 100 wt %, and the propylene-ethylene random copolymer (B) has a melt flow rate of 2-10 g/10 minutes as measured at 230° C. under a load of 2.16 kgf.