A Simplified Comprehensive Kinetic Scheme for Modeling of Ethylene/1-butene Copolymerization Using Ziegler-Natta Catalysts

摘要

A simplified kinetic scheme of eythylene/α-olefin copolymerization has been developed by adding reactions responsible for the unusual kinetic behavior to a general mechanism. The estimation of rate constants has been simplified by making physically meaningful initialrnguesses. Rate constants affecting yield, MWD and comonomer content have been estimated separately. Experiments were designed to investigate the effects of each rate constant independently. The obtained rate constants show that the sites which are responsible for formation of short chains with higher 1-butene content are more active at the beginning of polymerization, while the sites which are responsible for formation of longer chains with lower 1-butene units are more active at the final stages of polymerization.