Titanium-biphenoxide catalysts for ethylene polymerization

Titanium (IV) complexes containing sterically bulky ligands such as 2, 2′- methylenebis (4-methyl-6-tert butyl phenol) (MBTP) were synthesized by stoichiometric reaction between Ti(IV)alkoxide or halide and the biphenol. These catalyst precursors formulated as [Ti(O^O)RR′] were characterized by physicochemical and spectroscopic methods. The newly prepared Titanium biphenoxides were found to be active in polymerization of ethylene at high temperatures and pressures in combination with ethylaluminum sesquichloride (Et₃Al₂Cl₃) as co-catalyst. The linear polyethylene obtained by this route exhibit low-molecular weights, are highly crystalline and display narrow polydispersities. The physical properties of polymers thus obtained closely resemble specialty PE waxes that are industrially important for surface coating, ink formulations and mar resistance applications.