Polymerization characteristics of in situ supported pentamethylene bridged dinuclear zirconocene

Abstract

An in situ supporting method was applied to newly synthesized [(CH2)(5)(C5H4)(2)][(C9H7)ZrCl2](2) catalyst and other commercial catalysts, and its effects on the polymerization characteristics of these catalysts were examined through reaction experiments. The changes in the molecular weight distribution varied depending on the metallocene catalyst while the changes in the catalytic activity, average molecular weight and the melting point showed the same trend. The reason for the decrease in the molecular weight with in situ supporting was discussed in relation to the co-catalysts. The polymerization characteristics of each catalyst also varied according to the alkyl aluminum, and so it is important to select a proper co-catalyst or a combination of co-catalysts to obtain a desired polymer product from each metallocene catalyst supported by in situ method. (C) 2002 Elsevier Science B.V. All rights reserved.