Polymerization catalysts

本发明涉及可用于制备基本上末端不饱和的聚烯烃的催化剂体系，它包括含基于三氟甲磺酸根、二酮酸或β-酮酯的金属茂配合物。优选的配合物适合与助催化剂一起用于制备具有97％以上亚乙烯基末端不饱和的聚合物，所述聚合物适合于官能化并随后用作燃料和润滑剂添加剂、分散剂、蜡改进剂、粘度指数改进剂等。 Catalyst system suitable for preparing substantially terminally unsaturated atactic polymers or copolymers of alpha-olefins having a molecular weight (Mn) in the range 200-500,000. The catalyst system includes a metallocene of the formula:wherein CpH is a cyclopentadienyl ligand, each R represents an alkyl or an aryl substituent on the CpH ligand or two R's may be joined together to form a ring, or the Rs in each CpH group when taken together represents an Si or C bridging group linking two CpH groups wherein the Si or C group may itself be substituted by hydrogen atoms or C1-C3 alkyl groups, M is a metal selected from hafnium, zirconium and titanium, Z is selected from a hydrogen atom, a trifluoromethane sulphonate, an alkyl and an aryl group, Y is selected from a, 1,3-diketonate and a beta-ketoester arion, and each of m and n is same or different and has a value from 0 to 5.