| 摘要 |
PURPOSE: To obtain a polypropylene composition containing talc and a specific mixture of a block copolymer and a copolymer rubber, having excellent impact resistance, hardness, rigidity, heat-resistance and moldability and useful as an interior material of automobile. CONSTITUTION: This polypropylene copolymer contains (A) 55-85wt.% of a propylene-ethylene block copolymer having a melt flow rate(MFR) of 10-25g/10min, (B) 0-20wt.% of an ethylene-propylene copolymer rubber having an MFR of 0.5-20g/10min and an ethylene-butene copolymer rubber having an MFR of 0.2-30g/10min and (C) 10-25wt.% of talc having an average particle diameter of <=5μm. The component A contains 3-20wt.% (based on 100wt.% of the component A) of a propylene-ethylene copolymer block (the intrinsic viscosity of the block is 3-5dL/g and the ethylene content in the copolymer block is 30-50wt.%) and a propylene homopolymer block satisfying the formulaΔHm >=25.5+1.583logMFR whereinΔHm is heat of fusion.
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