| abstract |
This invention relates to bidentate transition metal catalyst compositions useful for coordination polymerization of alpha olefin monomers. The novel catalyst compounds are prepared by: (1) reacting a transition metal trihalide, a transition metal trialkoxide or mixed tri(halide/alkoxide), or the adducts of these materials with Lewis bases, with two equivalents of a bidentate chelating ligand; or (2) reacting two equivalents of the same or different transition metal (+3) tris chelates with one equivalent of a transition metal trihalide or its adduct with Lewis bases. The invention chelating ligands are those which contain at least two, and preferably not more than two, hetero atoms such as O, N, P, or S, separated by a hydrocarbon radical providing sufficient chain length so as to allow both hetero atoms to chelate the same metal atom. The chelating ligand must have at least one easily removable positive ion which is lost on chelation to afford a uninegative, bidentate ligand. |