Preparation of Ethylene/Polyhedral Oligomeric Silsesquioxane(POSS) Copolymers with rac-Et(Ind)2ZrCl2/MMAO Catalyst System

To prepare the organic/inorganic hybrid copolymer, the norbomene derivatives of polyhedral oligomeric silsequioxane(POSS) such as norbomenylethyl-POSS (N-POSS) and dimethyl(norbomenylethyl)silyloxy-POSS(N-Si-POSS) had been copolymerized with ethylene by catalyst system of rac-Et(Ind)2ZrCl2/modified methylaluminoxane(MMAO). The catalytic activity decreased with the feed amount of POSS comonomer, and it was found that the reactivity of N-Si-POSS was larger than that of N-POSS. The unreacted POSS monomer was removed completely by washing the copolymerization product with n-hexane. The melting point of copolymer decreased with POSS content while the thermal stability, especially oxidation stability of copolymer was improved in a great extent relative to conventional polyethylene.