A Robust Ni(ll) α-Diimine Catalyst for High Temperature Ethylene Polymerization

摘要

Sterically demanding Ni~(II) α-diimine pre-catalysts were synthesized utilizing 2,6-bis(diphenyl-methyl)-4-methyl aniline. When activated with methyl-aluminoxane, the catalyst NiBr_2(ArN=C(Me)-C(Me)= NAr) (Ar = 2,6 bis(diphenylmethyl)-4-methylbenzene) was highly active, produced well-defined polyethylene at temperatures up to 100 ℃ (M_w/M_n = 1.09-1.46), and demonstrated remarkable thermal stability at temperatures appropriate for industrially used gas-phase polymerizations (80-100 ℃).