Improvements in and relating to polymerisation catalysts and the polymerisation of ethylene therewith

摘要

Ethylene is polymerized to a normally solid polymer by contact with a catalyst composition comprising a hydrocarbon-soluble aluminium trihalide, a compound of formula RAIX2 (R = a hydrocarbon or halogenated hydrocarbon group, X = Cl, Br or I) and 0,001-0,05 moles per mole of combined Al compounds of a vanadium compound in which the vanadium is divalent or is capable of being reduced to the divalent state, the vanadium compound being hydrocarbon soluble or forming a hydrocarbon souble vanadium compound by interaction with the aluminium trihalide. In examples, the catalyst ingredients used are VCl2, VCl3, AlCl3, AlBr3, MeAlCl2, PhAlCl2, PhAlBr2, n- and i-BuAlBr2. The catalyst compositions of the invention may contain a complex of structure:- The polymerization process may also be used for the production of copolymers of ethylene with up to 15 mole % propylene or higher olefins. Specification 883,498 and Belgian Specification 530,617 are referred to.