Distribution of active centres in Ziegler-Natta catalysts based on TiCl3 by their activity and stereospecificity

A fractional poisoning method has shown that all groups of Ziegler catalyst centres, both stereospecific and non-stereospecific, have a similar distribution of propagation rate constants. The most regular and highly molecular isotactic fraction is quite uniform by stereoregularity. Most of the poison-resistable part of active centres in δTiCl 3 -AlEt 3 systems have properties similar to those of initial system TiCl 3 -AlEt 2 Cl, which may be caused by different adsorption abilities of co-catalysts AlEt 3 and AlEt 2 Cl at TiCl 3 surface. Values n p and k p have been estimated for δTiCl 3 (TAC)-AlEt 3 system.