Novel Ziegler/Natta Catalysts Based on Titanium (IV) Complexes with Biscarboxylato Ligands and Organoaluminium Compounds for the Copolymerization of Ethylene with 1-Hexene

The co-polymerization of ethylene with 1-hexene has been performed with titanium precursors based on carboxylato ligands in the presence of organoaluminium compounds as activators to afford linear low-density polyethylenes (LLDPEs). The influence of the polymerization parameters was studied with particular reference to the type and amount of catalyst components, solvent, temperature, ethylene pressure, 1-hexene concentration. The chloro-substituted bis-carboxylato titanium complex resulted the most active precursor in the co-polymerization, allowing to obtain copolymers with modulable composition in the 1e5 mol% range of 1-hexene units. The obtained copolymers were characterized by thermal analysis, X-ray diffraction spectroscopy, FTIR and NMR techniques.