Olefin polymerization catalysts

A process for the polymerization of one or more olefins comprising conducting the polymerization in the presence of a catalyst system comprising: (A) a Group IV B transition metal component of the formula: ##STR5## wherein M is Zr, Hf or Ti; (C.sub.5 H.sub.5-y-x R.sub.x) is a cyclopentadienyl ring which is substituted with from zero to five groups R, "x" is 0, 1, 2, 3, 4, or 5 denoting the degree of substitution, and each R is, independently, a radical selected from a group consisting of C.sub.1 -C.sub.20 hydrocarbyl radicals, C.sub.1 -C.sub.20 substituted hydrocarbyl radicals wherein one or more hydrogen atoms are replaced by a halogen atom, C.sub.1 -C.sub.20 hydrocarbyl-substituted metalloid radicals wherein the metalloid is selected from the Group IV A of the Period Table of Elements and halogen radicals or (C.sub.5 H.sub.5-y-x R.sub.x) is a cyclopentadienyl ring in which two adjacent R-groups are joined forming C.sub.4 -C.sub.20 ring to give a saturated or unsaturated polycyclic cyclopentadienyl ligand; (JR'.sub.z-1-y) is a heteroatom ligand in which J is an element with a coordination number of two from Group VI A of the Period Table of Elements, each R' is, independently a radical selected from a group consisting of C.sub.1 -C.sub.20 hydrocarbyl radicals, substituted C.sub.1 -C.sub.20 hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen atoms, and "z" is the coordination number of the element J; each Q is, independently any univalent anionic ligand or two Q's are a divalent anionic chelating agent; "y" is 0 or 1 when w is greater than 0; y is 1 when w is o, when "y" is 1, B is a covalent bridging group containing a Group IV A or V A element; L is a Lewis base where "w" denotes a number from 0 to 3; and (B) an alumoxane.