POLYMERIZATION OF STYRENE BY RARE-EARTH COORDINATION CATALYSTS

Polymerization of styrene has been investigated using homogeneous rare earth coordination catalysts based on a neodymium compound, triisobutylaluminium and/or a third component. Satisfactory results have been obtained by aging catalyst components for 1 h at 60°C, and polymerizing styrene in hexane at 60°C. The addition of CCl4 as a third component to Nd(naph)3-Al(iso-Bu)3 system greatly increases catalytic activity. The order of catalytic activity of Nd compounds with different ligands for styrene polymerization is as follows: Nd(P507)3∼Nd(P204)3>Nd(naph)3>Nd(acac)3·3H2O. Both Nd(P507)3−Al(iso-Bu)3 and Nd(P204)3−Al(iso-Bu)3 systems prepared in the presence of monomer show high catalytic activity. A syndiotactic-rich polystyrene was obtained with Nd (naph)3−Al (iso-Bu)3- and/or a third component systems in hexane at 60°C. © 1990 The Society of Polymer Science, Japan.