Distinguishing chain growth mechanisms in metal-catalyzed olefin oligomerization and polymerization systems: C2H4/C 2D4 co-oligomerization/polymerization experiments using chromium, iron, and cobalt catalysts

Abstract

A series of co-oligomerization and copolymerization reactions of C 2H4/C2D4 (1:1) mixtures have been carried out using various transition metal catalysts based on Cr, Co, and Fe in combination with MAO. The oligomeric α-olefin products have been analyzed by GC and GC/MS, and the experimental results have been compared with the theoretical mass spectra derived from mathematical models. Solid polymer samples have been analyzed by 13C{1H} and 13C DEPT-135 NMR spectroscopy. C2H4/C2D4 co-oligomerization can be used as a method to differentiate between a metallacyclic or a Cossee-type chain growth mechanism in oligomerization systems. In the case of a metallacyclic mechanism, no H/D scrambling is ..