Co- and terpolymerization of ethylene with 1-butene and 1-decene by using Cp2ZrCl2-methylaluminoxane catalyst

Copolymerizations of ethylene/1-butene, and ethylene/1-decene and terpolymerization of ethylene/1-butene/1-decene were carried out in n-heptane with various concentrations of comonomer in the feed. Cp₂ZrCl₂-methylaluminoxane (MAO) was used as catalyst. When comonomers were added into the ethylene polymerization, the activity of the catalyst increased significantly and continued to do so as the concentration of the comonomer was increased. At the same time as the comonomer concentration and catalyst activity increased, the molecular weight and crystallinity of the polymers decreased. An important reason for the activity enhancement may, therefore, be that the comonomer takes part in the activation of catalytic centers, decreasing the activation energy required for monomer to insert into the active centers. Use of Cp₂ZrCl₂-MAO catalyst allowed the preparation of ethylene/1-decene copolymers containing 20 wt % of 1-decene. © 1993 John Wiley & Sons, Inc.