Methods of making magnesium/transition metal alkoxide complexes and polymerization catalysts made therefrom

摘要

A method of halogenating a precursor to form a polymerization procatalyst is disclosed whereby a magnesium/transition metal-containing alkoxide complex precursor is contacted with a halogenating agent selected from alkylaluminum halide, TiX4, SiX4, BX3, and Br2, where halide and X are reach respectively a halogen, and when an alkylaluminum halide, TiX4, SiX4, BX3, and Br2 are used as the halogenating agent, they are used together or in combination in a multi-step halogenation. The procatalyst then can be converted to an olefin polymerization catalyst by contacting it with a cocatalyst and optionally a selectivity control agent, and used to polymerize olefins in high yield with desired properties.