POLYPROPYLENE COMPOSITION

摘要

A polypropylene composition having well-balanced properties among low-temperature shock resistance, rigidity, heat resistance and transparency and comprising: [I] 20 to 95 % by weight of a polypropylene having (1) an isotactic pentad fraction of 0.900 to 0.949, (2) 0 to 1 molar % of 2,1- and 1,3-propylene units, (3) a weight-average molecular weight of 40,000 to 1,000,000, (4) a weight-average molecular weight to number- average molecular weight ratio of 1.5 to 3.8, and (5) such a solubility of the polypropylene in o-dichlorobenzene that when the solubility is determined by elevating the temperature of o-dichlorobenzene continuously or stepwise and determining a change in the solubility of the polypropylene with temperature, the main elution peak is obtained at 95 to 110 DEG C, and the amount of the components eluted at the main elution peak +/- 10 is at least 90 % of the whole components eluted at a temperature above 0, and [II] 5 to 80 % by weight of a propylene/ alpha -olefin copolymer comprising 10 to 90 % by weight of propylene units and 10 to 90 % by weight of other alpha -olefin units.