Polymerization with heterogeneous metalorganic catalysts. VI. Differences in polymerization activity of α‐olefins and some kinetic results on butene‐1 polymerization

Relative changes in polymerization activity of ethylene, propylene, and butene‐1 in Ziegler‐Natta polymerization were compared by use of TiCl 3 samples contaminated with O 2 and H 2 O to various extents. Catalyst depletion varied for the three monomers which supported the existence of different active centers. In butene‐1 polymerizations with the system Al(C 2 H 5 ) 2 Cl–TiCl 3 , the formation of active centers involves an irreversible and a reversible (adsorption) reaction, the former pertaining to the formation of Al(C 2 H 5 )Cl 2 and dependent upon the purity of the TiCl 3 . The kinetic treatment of the rate curves suggests a mixed order of catalyst deactivation and again points to the importance of Al(C 2 H 5 )Cl 2 .