An EPR Study of the Influence of the Component Ratio in the Titanium Tetrachloride-Acetophenone-Triisobutyl Aluminum Catalyst System on Selectivity and Stereospecificity in Copolymerization of Dienes with Olefins

摘要

Interaction between the components of the catalyst system TiCl_4-acetophenone-(iso-C_4H_9)_3Al used to catalyze the copolymerization of dienes with olefins at a temperature of -30 deg C, including alternating copolymerization, was stdied by EPR spectroscopy. It was assumed that the alternating copolymerization of isoprene with ethylene involves the formation in solution of Ti~(3+)(centre dot)mTi~(4+) complexes (m >= 1) containing a greater number of alkyl ligands than in the case of butadiene copolymerization with propylene.