Temperature dependence of copolymerization parameters in ethene/1-octene copolymerization using homogeneousrac-Me2Si(2-MeBenz[e]Ind)2ZrCl2/MAO catalyst

Abstract

Ethene was copolymerized with 1-octene using homogeneous MAO-activated rac-Me2Si(2-MeBenz[e]Ind)2ZrCl2 at constant ethene concentration with temperature varying between 0 and 60°C to determine a temperature dependence of copolymerization parameters. At constant 1-octene and ethene concentration (constant ethene/1-octene feed molar ratio) 1-octene incorporation decreased with increasing temperature. Furthermore, when ethene/1-octene molar ratio was varied by varying the temperature keeping 1-octene concentration and ethene pressure constant, increasing temperature accounted for lower molecular masses without affecting 1-octene incorporation. An explanation for the observed temperature dependence of the copolymerization parameters is presented, considering the solution-enthalpy of the gaseous ethene in the solvent. In all cases amorphous poly(ethene-co-1-octene) with 1-octene content varying between 20 and 40 mol % was obtained. © 1997 John Wiley & Sons, Inc.