Homogeneous metallocene/MAO-catalyzed polymerizations of polar norbornene derivatives: copolymerizations using ethene, and terpolymerizations using ethene and norbornene

摘要

Terpolymerizations of norbornene derivatives containing different functional substituents were carried out with ethene and norbornene using the homogeneous catalyst system iPr[CpInd]ZrCl2/MAO. The norbornene derivatives 5-norbornene-2-methanol and 5-norbornene-2-carboxylic acid were prereacted with triisobutylaluminium to prevent the deactivation of the catalyst. C-13 NMR studies revealed the composition of the polymer. The incorporation rate was 5-12 mol-% at a content of 50 mol-% of the norbornene derivative in the monomer feedstock. IR-GPC coupled experiments confirmed the homogeneous composition of the polymer. In addition, we investigated the ethene copolymerization and the etheneorbornene terpolymerization using the trialkylsilyl protected norbornene derivatives such as 5-norbornene-2-methyleneoxytriethylsilane and 5-norbornene-2-methyleneoxy-tert-butyldimethylsilane. These norbornene derivatives reveal an incorporation rate of 5-6 mol-% in the polymer at a content of 20 mol-% in the monomer feedstock. [References: 15]