| abstract |
A process for producing alpha -olefins is provided which comprises: milling (A) a trivalent metal halide together with (B) a divalent metal compound, in a specified ratio of (A) to (B), and reacting them to obtain a solid product (I); reacting with this product (I), (C) an electron donor and (D) an electron acceptor, (C) and (D) being respectively reacted once or more up to ten times, and TiCl4 being employed as the electron acceptor at least once, to obtain a solid product (II); combining with this product (II), (E) a trialkylaluminum and (G) a reaction product of an electron donor with an electron acceptor, and in this combination, subjecting a part or the whole of the catalyst components (product (II), (E) and (G)) to polymerization treatment by reacting (F) an alpha -olefin at least in the presence of the product (II) and trialkylaluminum, to obtain a preliminarily activated catalyst; and polymerizing an alpha -olefin in the presence of this catalyst. The above catalyst is suitable particularly for gas phase polymerization or suspension or bulk polymerization followed by gas phase polymerization, and affords a highly crystalline alpha -olefin polymer having a good particle form, with a high yield. |