Ethylene Polymerization Catalyzed by Cyclohexyl-bridged Cyclopentadienyl Titanium Complex

Cyclohexyl-bridged cyclopentadienyl titanium catalyst of the type [(CH2)5C(C5H4)2] TiCl2(C2) has been prepared by treatment of the lithium salt of cyclopentadiene ligand with TiCl4·2THF in THF solution.The complex C2 were characterized by 1H-NMR,13C-NMR and element analyse.Activated by MAO,complex C2 is an efficient catalyst in the polymerization of ethylene.Complex C2 displayed very high activity for ethylene polymerization under the reaction temperature of 60～70 ℃,and the viscosity-average molecular weight of polyethylene is more than 3.4×105 when reaction temperature is no more than 60 ℃.The molecular-weight distribution measured by gel permeation reached 2.69.High melting points measured by DSC indicates that the polyethylene produced by complex C2 is high linearity and high crystallinity.