2,6-Dibenzhydryl-N-(2-phenyliminoacenaphthylenylidene)-4-chloro- aniline nickel dihalides: Synthesis, characterization and ethylene polymerization for polyethylenes with high molecular weights

Abstract A series of 2,6-dibenzhydryl- N -(2-phenyliminoacenaphthylenylidene)-4-chloroanilines ( L1 – L5 ) and their nickel halide complexes LNiX 2 (X = Br, C1 – C5 ; X = Cl, C6 – C10 ) were synthesized. All organic compounds were characterized by FT-IR and NMR spectroscopy and elemental analysis. The nickel complexes were characterized by FT-IR spectroscopy, elemental analysis and their structures were determined by single-crystal X-ray diffraction. Upon activation with MAO, all of these nickel complexes showed high activities (up to 10 7  g of PE (mol of Ni) −1  h −1 ) for ethylene polymerization. The resulting polyethylenes possess high molecular weights ( M w up to 10 6  g mol −1 ) and feature high degrees of branching. The MM-QEq method was employed to assess the ligands' effects on catalytic activities. The results show that higher net charges on the nickel core correlate directly with higher measured activities.