文献类型：期刊文献

英文题名：Novel 2-propenyl cyclopentadienyl lanthanide complexes as single component methyl methacrylate (MMA) polymerization catalysts

作者：Qian, Yanlong[1]; Bala, Muhammad D[1]; Yousaf, Muhammad[1]; Zhang, Hao[1]; Huang, Jiling[1]; Sun, Junquan[2]; Liang, Chengfeng[2]

机构：[1]E China Univ Sci & Technol, Organomet Chem Lab, Shanghai 200237, Peoples R China;[2]Zhejiang Univ, Dept Chem Engn, Hangzhou 310027, Peoples R China

年份：2002

卷号：188

期号：1-2

起止页码：1

外文期刊名：JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

收录：;EI(收录号：2002377089769);WOS:【SCI-EXPANDED(收录号:WOS:000177937800001)】；

语种：英文

外文关键词：lanthanides; 2-propenyleyelopentadiene; methyl methacrylate; single-component catalyst

摘要：A new set of allyl-functionalized cyclopentadienyl (Cp') lanthanocenes were synthesized and characterized by MS, IR and EA. A structure in which the lanthanide metal is a nine-coordinate center solvated by two THF molecules was proposed. No evidence of intramolecular coordination of the alkenyl C=C to the central metal was observed. Single component bulk polymerization of MMA catalyzed by Cp' yttrocene indicated that at the optimum condition of 40degreesC and MMA/catalyst molar ratio of 400:1 a predominantly syndiotactic (rr > 70%) polymer with M-n > 500,000 and molecular weight distribution (M-w/M-n) < 1.4 is obtained. The effects of variation in temperature, time of polymerization and initiator concentration was also studied. The title catalysts showed moderate activity for MMA/catalyst molar ratio of up to 1200:1. At a molar ratio of 800:1 a polymer M-n = 1.6 x 10(6) was obtained. The electron donating influence of the functional group on catalyst activity was discussed. The effects of co-catalysts on the polymerization were also studied. (C) 2002 Elsevier Science B.V. All rights reserved.