Effect of Catalyst Composition on Chain-End-Group of Polyethylene Produced by Salen-Type Complexes of Titanium, Zirconium, and Vanadium

A study was conducted to demonstrate that the occurrence of a chain termination reaction in ethylene polymerization was linked to the type of catalyst. It was demonstrated that zirconium bis(phenoxyimme) catalysts produced moderate to high molecular weight polyethylenes with equal numbers of vinyl and methyl groups as chain end structures. The verified the effects of the composition of the catalytic systems that contained salen-type complexes and investigated the effects of the type of the organoaluminium compound and the type of transition metals in the complex on the microstructure of obtained polyethylenes. Another analysis was performed for polyethylene, which was produced with the use of immobilized titanium and vanadium complexes. 1H NMR and FTIR spectrometric methods were ALSO used to analyze chain end structures in polyethylene synthesized with salen-type complexes of titanium, vanadium, and zirconium.