Polymerization of olefins in the presence of catalyst prepared from organo zirconium-chromium mixtures

Claim 1

A process for polymerizing one or more α-olefins which comprises conducting said polymerization under Ziegler polymerization conditions in the presence of a catalyst which comprises (A) at least one member of the group consisting of (1) at least one zirconium compound, represented by the empirical formula ##STR3## wherein R is a hydrocarbon group having from 1 to about 12 carbon atoms; (2) at least one hydrocarbon soluble chromium compound represented by the empirical formula ##STR4## wherein R is a hydrocarbon group having from 1 to about 12 carbon atoms and a has a value equal to the valence of Cr; and (3) a mixture of components (1) and (2) in a mole ratio of component (2) to component (1) of from about 0.05:1 to about 10:1; (B) a solid catalyst support containing magnesium prepared by reacting (a) a compound represented by the empirical formula MgR" 2 .xAlR" 3 wherein each R" is independently a hydrocarbyl or hydrocarbyloxy group having from 1 to about 20 carbon atoms and x has a value from about zero to about 10 with (b) a halide source selected from non-metallic halides and metallic halides; (C) a tetrahydrocarbyloxy titanium or titanium halide compound; and (D) an organometallic activating agent; wherein the Mg:(Cr+Zr) atomic ratio is from about 1:1 to about 100:1; the Al:(Cr+Zr) atomic ratio is from about 1:1 to about 200:1; the (Cr+Zr):Ti atomic ratio is from about 0.5:1 to about 20:1; and the excess X:Al atomic ratio is from about 0.0005:1 to about 5:1.