Study on polymerization of ethylene with Cp2ZrCl2/aluminoxanes

Ethylene polymerization with Cp2ZrCl2/different aluminoxanes was investigated. Based on comparison of activity, molecular weight and molecular weight distribution of polyethylene obtained by different aluminoxanes, the effect of aluminoxanes on ethylene polymerization were discussed and the co-aluminoxane phenomenon was proposed. The introduction of a different alkyl group into aluminoxane greatly changes its regular cluster structure and therefore different coordinated aluminum atoms are presented. The increment of multiple types of aluminum atoms in aluminoxane improves not only the higher conversion of metallocene into the active site, but also the high stability of the counterion of the aluminoxane–anion complex in metallocene catalyst which leads to a high activity of mixed aluminoxane and a broad molecular weight distribution of related products.