Injection-molded article

An injection-molded large-sized exterior part of an automotive vehicle, said part being formed of a material comprising:

• (A) polypropylene in an amount ranging from 50 to 70 weight %, said polypropylene containing ethylene in an amount not more than 15 weight % relative to said polypropylene and having a MFR (at 230.degree. C.) ranging from 5 to 60 g/10 min.;
• (B) ethylene-propylene copolymer rubber polymerized in the presence of a vanadium-based catalyst, in an amount ranging from 5 to 30 weight %, said copolymer containing propylene in an amount ranging from 20 to 40 weight % relative to said ethylene-propylene copolymer rubber and having a Mooney viscosity ML.sub.1+4 (100.degree. C.) ranging from 20 to 80;
• (C) ethylene-propylene copolymer rubber polymerized in the presence of a titanium-based catalyst, in an amount ranging from 5 to 45 weight %, said copolymer containing propylene in an amount ranging from 30 to 70 weight % relative to said ethylene-prolylene copolymer rubber and having a Mooney viscosity ML.sub.1+4 (100.degree. C.) ranging from 20 to 75;
• and
• (D) polyethylene in an amount not more than 10 weight %, said polyethylene having a MFR (at 190.degree. C.) ranging from 5 to 50 g/10 min.,
• wherein said injection-molded article has an average thickness ranging from 2 to 6 mm, a flexural elastic modulus ranging from 3000 to 6000 kg/cm.sup.2, and a coefficient of linear expansion not higher than 8.times.10.sup.-5 /.degree.C.

A bumper of an automotive vehicle, formed of a material comprising:

• (A) polypropylene in an amount ranging from 50 to 70 weight %, said polypropylene containing ethylene in an amount not more than 15 weight % relative to said polypropylene and having a MFR (at 230.degree. C.) ranging from 5 to 60 g/10 min.;
• (B) ethylene-propylene copolymer rubber polymerized in the presence of a vanadium-based catalyst, in an amount ranging from 5 to 30 weight %, said copolymer containing propylene in an amount ranging from 20 to 40 weight % relative to said ethylene-propylene copolymer rubber and having a Mooney viscosity ML.sub.1+4 (100.degree. C.) ranging from 20 to 80;
• (C) ethylene-propylene copolymer rubber polymerized in the presence of a titanium-based catalyst, in an amount ranging from 5 to 45 weight %, said copolymer containing propylene in an amount ranging from 30 to 70 weight % relative to said ethylene-prolylene copolymer rubber and having a Mooney viscosity ML.sub.1+4 (100.degree. C.) ranging from 20 to 75;
• and
• (D) polyethylene in an amount not more than 10 weight %, said polyethylene having a MFR (at 190.degree. C.) ranging from 5 to 50 g/10 min.,
• wherein said injection-molded article has an average thickness ranging from 2 to 6 mm, a flexural elastic modulus ranging from 3000 to 6000 kg/cm.sup.2, and a coefficient of linear expansion not higher than 8.times.10.sup.-5 /.degree.C.