NMR study of branched polyethylenes obtained with combined Fe and Zr catalysts

Abstract

The products obtained with the system {[(ArN=C(Me))2C5H3N]FeCl2}/MAO (Ar = 2-C6H4(Et)) (1) and the ones obtained by the use of 1 in conjunction with Me2SiInd2ZrCl2/MAO (2) or EtInd2ZrCl2/MAO (3) were completely characterized by 1H NMR and 13C NMR. Catalyst 1 gives mainly linear α-olefins of molecular weights close to 2000 g/mol and a low amount of alkanes. The use of 1 with 2 or 3 using only ethylene as monomer gives branched polyethylene with ethyl, butyl, and mainly long branches. Some amount of unreacted α-olefin was also found in some cases, especially in reactions where a high ratio Fe to Zr was used.