Ethene−Norbornene Copolymerization Using Homogenous Metallocene and Half-Sandwich Catalysts: Kinetics and Relationships between Catalyst Structure and Polymer Structure. 1. Kinetics of the Ethene−Norbornene Copolymerization Using the [(Isopropylidene)(η⁵-inden-1-ylidene-η⁵-cyclopentadienyl)]zirconium Dichloride/Methylaluminoxane Catalyst

Abstract

The kinetics of the ethene-norbornene copolymerization using the [(isopropylidene)(eta5-inden-1-ylidene-eta5-cyclopentadienyl)]zirconium dichloride (iPr[IndCp]ZrCl2)/methylaluminoxane catalyst has been investigated at 70 degreesC in a concentrated solution of norbornene in toluene and an ethene pressure ranging from 4 to 60 bar (58-870 psi). The ethene reaction rate has been measured during the copolymerization process at varying reactant concentrations. The reaction orders and rate constants were determined and compared to the corresponding values of the ethene and norbornene homopolymerizations. It was found that kEhomo > kEco and kNhomo < kNco. The copolymerization parameters are r1 = 0.9 and r2 = 0.05.