Influence of ligands and cocatalyst on the activity in ethylene polymerization of soluble titanium complexes

Article abstract of DOI:10.1016/0304-5102(93)E0290-W

Known and new titanium complexes bearing alkoxy, phenoxy, carboxylate and cyclopentadienyl ligands in addition to chlorine have been tested towards ethylene polymerization after activation with aluminum alkyls (AlR₃) or methylalumoxane (MAO). In the absence of cyclopentadienyl ligands the optimal productivity obtained is very similar either with AlR₃ or MAO, but higher MAO/Ti than AlR₃/Ti ratios are necessary. In the case of complexes with the Cp ligand much better productivity can be obtained with high MAO ratios thus confirming that under these conditions a different activation mechanism is operative.