Rare-Earth Metal Complexes as Catalysts for Syndiospecific Styrene Polymerization

Rare-Earth Metal Complexes as Catalysts for Syndiospecific Styrene Polymerization 

KLAUS BECKERLE and JUN OKUDA RWTH Aachen University, Aachen, Germany 

This chapter summarizes the current knowledge on group 3 metal catalysts for syndiospecific polymerization, ft is organized according to the nature of the ligand system used and should provide some systematic insight into this emerging class of polymerization catalysts. 

Syndiotactic Polystyrene, Edited by Jurgen Schellenberg Copyright 2010 John Wiley Sons, Inc. 

In contrast to the large number of publications on group 4-based catalysts for syndiospecific styrene polymerization, reports on analogous rare-earth metal catalysts are stiU hmited [5], Early investigations on neodymium-based sandwich complexes (1-3) activated by methylaluminoxane (MAO) (Fig. 7.1) have shown that these systems are promising candidates for styrene polymerization catalysis with the resulting polymers syndiotactically enriched. The selectivity as well as the activity of these systems are moderate [6]. 

---