Silica-magnesium bisupport (SMB) was prepared by a sol-gel method for use as a support for metallocene and metallocene/Ziegler-Natta hybrid catalysts. SMB was treated with methylaluminoxane (MAO) prior to catalyst immobilization. The supported heterogeneous catalysts were applied to the ethylene copolymerization with 1-hexene. The h-copolymer (ethylene-hexene copolymer produced by metallocene/Ziegler-Natta hybrid catalyst) showed two melting points and broad molecular weight distribution. The differences in physical properties between h-copolymer and m-copolymer (ethylene-hexene copolymer produced by metallocene catalyst) could be explained by the differences in chemical composition and side chain distributions of the produced copolymers. (c) 2006 Elsevier B.V. All rights reserved.