| 摘要 |
PURPOSE:To obtain a polyolefin of wide MW distribution and good moldability, by prepolymerizing an olefin in the presence of a specified catalyst system and effecting the main polymerization. CONSTITUTION:An olefin is prepolymerized in the presence of a catalyst compris ing a titanium compound (A) which is supported by an inorganic carrier treated with an electron-donating compound or untreated, 0.3-20mol, per mol of compo nent A, of an organoaluminum compound (B) of the formula: RAnAlX3-n (wherein R is a 1-20C alkyl, X is a halogen or H and 1<n<=3) and, as optional components, 0.001-3mol, per mol of component A, of an electron-donating compound (C) and 0.1-5mol, per mol of component A, of an organometallic intramolecular coordination compound (D) of formula I or II (wherein M is a metal, Y is a ligand atom or group and n >=1), e.g., (3-ethoxypropyl)- ethylaluminum hydride, which is added in the prepolymerization and/or the main polymerization, to form 1-100g of a polyolefin per g of compnent A, and the main polymerization is performed.
|
