Supported polymerization catalyst

Abstract

A catalyst useful in the polymerization of olefins is disclosed. The catalyst is produced by initially treating an inert inorganic compound to remove surface hydroxy groups. The thus treated inorganic compound is contacted with a hydrocarbon soluble magnesium compound in a second step. The product of this second step is contacted with a modifying compound selected from the group consisting of silicon halides, boron halides, aluminum halides, alkyl silicon halides, hexaalkyl disilazanes and mixtures thereof in a third step. The product of this third step is contacted a vanadium compound having the structured formula V(O).sub.s X.sup.1.sub.4-s, where X.sup.1 is halogen; and s is 0 or 1, a first titanium-containing compound having the structural formula Ti(OR.sup.2).sub.n X.sup.2 m, where R.sup.2 is hydrocarbyl; X.sup.2 is halogen; n is an integer of 1 to 4; and m is 0 or an integer of 1 to 3, with the proviso that the sum of n and m is 4, and a second titanium-containing compound having the structural formula TiX.sup.3 (OR.sup.3).sub.q, where X.sup.3 is halogen; R.sup.3 is hydrocarbyl; p is an integer of 1 to 4; and q is 0 or an integer of 1 to 3, with the proviso that the sum of p and q is 4 and that the first and the second titanium-containing compounds are not identical. A process for polymerizing olefins, using the catalyst of this disclosure is also provided.