Highly active copolymerization of ethylene with 10-undecen-1-ol using phenoxy-based zirconium/methylaluminoxane catalysts

摘要

Activated with methylaluminoxane (MAO), phenoxy-based zirconium complexes bis[(3-(BU)-B-t-C6H3-2-O)-CH=NC6H5]ZrCl2, bis[(3,5-di-(BU)-B-t-C6H2-2-O)-PhC=NC6H5] ZrCl2, and bis[(3,5-di-Bu-t-C6H2-2-O)-PhC=N(2-F-C6H4)]ZrCl2 for the first time have been used for the copolymerization of ethylene with 10-undecen-1-ol. In comparison with the conventional metallocene, the phenoxy-based zirconium complexes exhibit much higher catalytic activities [> 10(7) g of polymer (mol of catalyst)(-1) h(-1)]. The incorporation of 10-undecen-1-ol into the copolymers and the properties of the copolymers are strongly affected by the catalyst structure. Among the three catalysts, complex e is the most favorable for preparing higher molecular weight functionalized polyethylene containing a higher content of hydroxyl groups. Studies on the polymerization conditions indicate that the incorporated commoner content in the copolymers mainly depends on the comonomer concentration in the feed. The catalytic activity is slightly affected by the Al-(MAO)/Zr molar ratio but decreases greatly with an increase in the polymerization temperature. (c) 2005 Wiley Periodicals, Inc.