| 摘要 |
The present invention provides olefin polymerization catalysts and processes for preparing a polypropylene and a propylene block copolymer using said olefin polymerization catalysts. The olefin polymerization catalyst (1) of the invention is formed from: [I-1] a contact product obtained by contacting: (A) a solid titanium catalyst component, (B) an organometallic compound catalyst component, and (C) a specific organosilicon compound; [II-1] (D) a specific polyether compound; and optionally, [III] an organometallic compound catalyst component. The olefin polymerisation catalyst (2) of the invention is formed from: [I-2] a contact product obtained by contacting: (A) a solid titanium catalyst component, (B) an organometallic compound catalyst component, and (D) a specific polyether compound; [II-2] (C) a specific organosilicon compound; and optionally, [III] an organometallic compound; catalyst component. In the processes for preparing polypropylene propylene is polymerized in the presence of the above-mentioned olefin polymerization catalysts and highly isotactic polypropylene can be obtained. The processes for preparing a propylene block copolymer comprises the steps of polymerizing propylene to form a polypropylene component and copolymerizing ethylene and an alpha -olefin of 3 to 20 carbon atoms to form an ethylene/ alpha -olefin copolymer component, in an optional order, in the presence of the specific polymerization catalysts, which is highly isotactic and the rubber component has a high intrinsic viscosity [ eta ]. |
