The advances in homopolymerization of polar monomers and copolymerization of nonpolar monomers with polar monomers based on CGC catalyst,half-metallocene catalyst,bis-metallocene catalyst,multinuclear metallocene catalyst,bridged metallocene catalyst,and non-metallocene catalyst are reviewed. The mechanism of polar monomer polymerization promoted by metallocene catalysts includes living radical polymerization and coordination polymerization.Polymer of polar monomer and copolymer of polar monomer with nonpolar monomer are prepared via metallocene catalysts. It not only expands the application of metallocene catalysts in polymer science,but also develops a kind of polar polyolefin resin featuring new performance.

The development in catalyst for broad or bimodal molecular weight distribution polyethylene prepared with the process of single-reactor was described. According to the composition and structure of the catalyst,the catalytic systems were classified as multi-component composite catalyst and mono-component catalyst. The multi-component composite catalysts were divided into metallocene/Ziegler-Natta composite catalyst,different metallocene composite catalyst,chromium based/Ziegler-Natta composite catalyst,metallocene/late transition metal composite catalyst,non-metallocene single site/metallocene composite catalyst,non-metallocene single site/Ziegler-Natta composite catalyst and different late transition metal composite catalyst. The multi-composite catalyst acted as individual active species,which had different kinetic responses,such as different propagation,termination,and transfer rate constants,and as a result,produced a blend of polymeric chains with two or more predominant molecular masses in ethylene polymerization via the process of single-reactor. The mono-component catalysts involved mononuclear metallocene catalyst,multinuclear metallocene catalyst and late transition metal catalyst and other mono-component catalyst. The mono-catalyst which was able to come into being various catalytic active centers could produce polyethylene with broad or bimodal molecular weight distribution in a single-reactor. To form different active species of the mono-component catalyst was probably resulted from that the catalyst was immobilized on different chemical or physical environmental supports and the center metal of the catalyst was coordinated or reacted with ligand,ancillary ligand cocatalyst as well as additive.