| 摘要 |
PURPOSE: To obtain an olefin polymer blow molding being excellent in rigidity, impact resistance, heat resistance, sanitariness and moldability and having scarcely discernible spider marks or weld marks and having a pearly appearance by using a block copolymer comprising a propylene homopolymer component (component A) and an ethylene/propylene copolymer component (component B), wherein components A and B have specified properties. CONSTITUTION: The product of the ratio between the intrinsic viscosities of components A and B and the ratio of the weights of components A and B should be in the range of 0.2-2.0, the ratio between the melt flow rates of both components should be in the range of 0.3-4, and the intrisic viscosity of component B should be 6.5 or below. It is desirable that the content of component B is 30-80wt.%, and the ethylene content of component B is 25-65%. The production of this copolymer by polymerization, e.g. vapor-phase polymerization is performed in such a way that the component A is first polymerized in the presence of a titanium-containing catalyst component, an organoaluminum component and an organosilicon compound, and polymerizing the component B. |
