Study of the Activity Enhancement Caused by the Addition of Hydrogen in Olefin Polymerization

Abstract

Propene and 1-butene polymerizations were performed using the catalyst system of MgCl₂ · TiCl₄ · diethylphtharate (DEP)/AIEt₃/ phenyltriethoxysilane (PES). In both polymerizations, the activities were enhanced more than three times hv the hydrogen addition, while in the catalyst system not containing DEP and/or PES, the degree of the activity enhancement was decreased to about one-third of that in the above catalyst system. The results of a kinetic study on l-butene short-term polymerization suggest that the said enhancement is not due to the increase of the number of active sites.