Process for the preparation of polymers of amp;agr;-olefins at high temperatures

摘要

A solution process for the preparation of high molecular weight homopolymers of ethylene and copolymers of ethylene and C.sub.3 -C. sub.12 &agr;-olefins is disclosed. The process involves feeding monomer, a particular coordination catalyst and hydrocarbon solvent to a reactor, polymerizing the monomer at a temperature of 105°-320° C. and recovering the polymer. The catalyst is obtained by combining solutions of titanium tetrahalide and of organoaluminum compound at a temperature of less than 30° C., heating the resulting admixture to a temperature of 150°-300° C. for a period of 10 seconds to 10 minutes and combining the thus heat-treated mixture with a solution of an organoaluminum compound. The catalyst thus obtained is fed to the process, without separation of any components of the catalyst. In an embodiment part of the titanium tetrahalide may be replaced with vanadium oxytrihalide.