High efficiency alpha-olefin polymerisation catalyst

摘要

A catalytic reaction prod. of (A), (B), (C), (D) and, if necessary, (E) is claimed. (A) is a tri- or tetra-valent Ti cpd. of formulae (i) TiXn(OR)4-n (where X is halogen; R is 1-20C hydrocarbyl; and n is 0-4); (ii) alpha- and/or gamma-TiCl3; or (iii) TiZ3(L)x (where Z is halogen; x is 1-6; and L is an electron donor of water, ketone, ether, amine or olefin). (B) is a zirconium cpd. of formula Zr(OR)xXy (where each R is a 1-20C hydrocarbyl; each X is a halogen; and x and y are 0-4 with x+y=4). - (C) is an organomagnesium cpd. opt. complexed with an organometallic cpd. to solubilise the organomagnesium cpd. in a hydrocarbon solvent. The complex is of formula MgR"z.xMR"y (where M is Al, Zn, B, Si, Sn or P; each R" is 1-20C hydrocarbyl(oxy); x is 0-10; and y is valence of M); (D) is (iv) an active non-metallic halide of formula R'X (where R' is H or an organic gp. at least as active as sec-butyl; and X is halogen) or (v) a metallic halide of formula MRy-aXa (where M is a gp.IIIa or (IV) a metal; R is hydrocarbyl(oxy); X is halogen; y is valence of M; and a is 1-y); (E) is an Al cpd. of formula AlRy'Xy" ; and y' and y" are 0-3 and The components are added in an order selected from (a) (in order) (C), (D), (E) then (A) and (B); (b) (D) if it contains Al, (C) then (A) and (B); and (c) (D) if it contains Al, (A) and (B) and then (C). so that the atomic ratios of Mg:Zr = (1-100):1, Al:Zr = (0.1-100):1, Zr:Ti = (0.5-50):1 and of excess X:Al = (0.0005-10):1. (E) is added if (C) and/or (D) provides insufficient quantities of Al. - The catalyst is used in the polymn. of alpha-olefins giving products which contain lower amts. of catalyst residues without catalyst removal than those using conventional catalyst after catalyst removal. The polymers have a relatively broader mol.wt. distribution and, at higher Zr amts., a lower melt index than corresp. catalysts without Zr cpds.