Binuclear and Hexanuclear Ti(IV) Complexes Supported by [OOOO]4–-type Ligand for Preparing Disentangled UHMWPE

Binuclear and hexanuclear titanium complexes stabilized by tetradentate [OOOO]4–-type ligand were active in ethylene polymerization in the presence of Et2AlCl/Bu2Mg binary co-catalyst, giving high molecular weight polyethylene. The binuclear complex showed significantly higher catalytic activity and thermal stability in comparison to mononuclear analogue. Ultra high molecular weight polyethylene (UHMWPE) samples were processed by a solid-state uniaxial deformation into high-strength (up to 2.5 GPa) and highmodulus (over 100 GPa) oriented film tapes, which indirectly indicates a low degree of entanglements between the macromolecular chains.