Study of the mechanism of propagation and transfer reactions in the polymerization of olefins by Ziegler‐Natta catalysts, 2. The influence of polymerization temperature on the kinetic characteristics of propagation

By quenching polymerization with radioactive carbon monoxide (14CO) data on the number of propagation centers (Cp) and the propagation rate constant (Kp) were obtained for the ethylene and propene polymerization in the presence of titanium trichloride at different temperatures. The values of Kp for ethylene and propene polymerization were found to be 8,0·105 e−13/(RT) and 3,0·105 e−23/(RT) l mol−1 S−1, respectively (activation energies in kJ mol−1). It was further found that at increasing polymerization temperature the steady‐state concentration of propagation centers increased when using Al(C2H5)3 and Al(C2H5)2Cl as cocatalysts, whereas it did practically not change in the case of Al(isobutyl)3. On the basis of these data several conclusions were drawn on the mechanism of propagation and the role of organoaluminium cocatalysts in this reaction.