Stereoselective polymerization traditional Ziegler-Natta initiators

Both traditional Ziegler-Natta and metal oxide Phillips-type initiators are used in suspension polymerizations (Secs. 8-4a, 8-4j) [Kaminsky, 2001], Both types of initiators are used for ethylene, but only the traditional Ziegler-Natta initiators are used for propene since Phillips-type initiators do not yield stereoselective polymerizations. 

A variety of other initiators have been studied for the stereoselective polymerization of 1,3-dienes [Coates, 2000 Cooper, 1979 Endo and Hatakeyama, 2001 Deal et al., 1999 Nath et al., 2002 Pasquon et al., 1989 Peluso et al., 1997 Porri and Giarrusso, 1989 Ricci et al., 1996 Senyek, 1987 Tate and Bethea, 1985 Visseaux et al., 2001]. Traditional Ziegler-Natta, metallocene, and other initiators yield remarkable results, surpassing the stereoselectivity by alkyllithium initiators. Table 8-11 shows the polymer structures obtained... 

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