Synthesis and characterization of ethylene-1-hexene copolymers prepared by using MgCl2(THF)2-supported Ziegler-Natta catalysts

Ethylene was copolymerized with 1-hexene over vanadium (VOCl3 and VCl4) and titanium (TiCl4,) catalysts supported on MgCl2(THF)(2) and activated with Et2AlCl. So far these catalyst systems have not been known as initiators of ethylene-1-hexene copolymerization. The vanadium catalysts were more active than the titanium catalyst and, at identical comonomer concentrations in the feed, gave rise to a greater incorporation of 1-hexene into the copolymer. Even at relatively low fractions of 1-hexene, the MgCl2(THF)(2)-supported catalysts affected much the copolymer properties like density, melting point and crystallinity.