Homogeneous and supported catalysts based on bis(imino)pyridyl Iron(II) complexes for ethylene polymerization

详细信息    查看全文

• 作者：V. A. Zakharov ; N. V. Semikolenova ; T. B. Mikenas ; A. A. Barabanov ; G. D. Bukatov ; L. G. Echevskaya and M. A. Mats¡¯ko
• 刊名：Kinetics and Catalysis
• 出版年：2006
• 出版时间：March 2006
• 年：2006
• 卷：47
• 期：2
• 页码：303-309
• 全文大小：178 KB

文摘

Data on ethylene polymerization on homogeneous and supported catalysts based on 2,6-bis(imino)pyridyl Fe(II) complexes activated by trialkylaluminums are considered (activity, the molecular-weight characteristics of polymers, the number of active sites, and the propagation rate constants). Unlike homogeneous systems, the supported catalysts prepared with the use of various carriers (SiO₂, Al₂O₃, and MgCl₂) exhibited high stability and activity at 70–80¡ãC and produced high-molecular-weight polyethylene with a broad molecular-weight distribution (MWD). The molecular weights and MWDs of polymers and the propagation rate constant depended on the nature of the carrier only slightly. The reasons for an unusual effect of an increase in the activity of the supported catalysts in ethylene polymerization in the presence of hydrogen are discussed.