Superactive and stereospecific catalysts. II. Kinetics of propylene polymerizations

Abstract
The kinetics of propylene polymerization by superactive CH‐catalyst prepared from toluene solution of MgCl2 · EH/PA/TiCl4–TEA/PES was investigated. The results are compared with CW‐catalyst prepared from crystalline MgCl2/EB/PC/TEA/TiCl4–TEA/MPT (abbreviations given in the text). The former is four times more active than the latter and produces more isotactic polypropylene. The CH‐catalyst has 25% of the Ti as isospecific sites as compared to 6.7% for the CW‐catalysts. These sites have the same rate constant of propagation so that the higher polymerization activity of the CH‐catalyst is attributable simply to a greater number of active sites. Differences in the kinetics of deactivation and of chain transfer for the two catalysts are described.

This publication has 8 references indexed in Scilit: