Amorphous Polyethylene by Tandem Action of Cobalt and Titanium Single-Site catalysts

A variety of branched polyethylenes, spanning from semicrystalline LLDPE to completely amorphous, rubbery PE, was obtained from ethylene by homogeneous tandem catalysis using combinations of CoCl2(N2BT) (1) (N2BT=[1-(6-benzo[b]thiophen-2-yl-pyridin-2-yl)-ethylidlene)-(2,6-diisopropyl-phenyl)-amine) and [(eta5-C5Me4)-SiMe2(tBuN)]TiCl2 (2) in the presence of MAO at 30 °C. The productivity reached a maximum of 4 570 kg PE (mol Ti h)-1 at (Chi)Co = 0.50, yielding a rubbery material with d25 = 0.868 g cm3 and Tg = 55 °C.