Synthesis, characterization and application of organolanthanide complexes (CH2=CHCH2CH2C5H4)2Ln-Cl•2THF (Ln = Sm, Y, Dy, Er) as methyl methacrylate (MMA) polymerization catalysts

The title complexes (CH2-CHCH2CH2C5H4)(2)Ln-Cl(.)2THF (Ln = Sm, Y, Dy, Er) were synthesized as air and moisture sensitive free-flowing oils that have been fully characterized by MS, EA and IR. The EA and IR results indicate the presence of coordinated THF molecules. No evidence of intra-molecular coordination of the butenyl side-chain was observed. In association with AL(i-Bu)(3), the complexes have shown high activity for the bulk polymerization of MMA. At a MMA/catalyst (MMA/cat) molar ratio of 2000, temperature of 80 C and polymerization time of 30 h, the catalyst system produced at a 70% conversion a syndiorich polymer (rr = 62%), M-n = 1.65 x 10(6). Effects of temperature, time and molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The result showed that higher temperature, longer time and Al/catalyst molar ratio = 10 are conditions suitable for polymerization. (C) 2002 Elsevier Science B.V. All rights reserved.