Homogeneous Tandem Catalysis of Bis(2-decylthioethyl)amine−Chromium Trimerization Catalyst in Combination with Metallocene Catalysts
journal contributionposted on 14.12.2004, 00:00 by Deon de Wet-Roos, John Thomas Dixon
Homogeneous tandem catalysis involving a highly selective, aluminoxane-activated bis(2-decylthioethyl)amine·CrCl3 complex for the synthesis of 1-hexene in tandem with a number of metallocene catalysts is discussed. Analysis by means of DSC, CRYSTAF, HT-GPC, 13C NMR, and FTIR suggests that copolymers of 1-hexene and ethylene are produced with significant selectivity toward 1-hexene as comonomer. The selectivity of 1-hexene incorporation by the metallocene catalysts follows the trend in the order [Me2Si(2-Me-Ind)2]ZrCl2 > [Me2Si(2,3,4,5-Me-Cp)(t-Bu-N)]TiCl2 > Cp2ZrCl2. The highly selective nature of the ethylene trimerization catalyst employed in this study means that the industrial application of tandem catalysis is becoming increasingly viable since it approaches conventional 1-hexene LLDPE in terms of polymer microstructure control.