Kinetic characteristics of chain propagation and transfer to aluminium alkyl in the high temperature polymerization of ethylene on Ziegler-type titanium-magnesium catalysts

Abstract

The concentrations of active propagation centres and rate constants for elementary acts of PE macrochain propagation and the limitations of its propagation by alumino-organic compounds in the polymerization of ethylene under conditions of the PE in a hydrocarbon solvent at 433 K on titanium-magnesium catalytic systems (based on a bulk catalyst and on a system with dissolved components), and also on a traditional Ziegler system based on titanium trichloride are determined by radiochemical methods. It is shown that titanium-magnesium catalytic systems have a several times higher content of active centres in their composition, and that the high temperature polymerization of PE under their action has larger values of the above constants than with the classical Ziegler system.