Nickel(II) isocyanide complexes as ethylene polymerization catalysts

Isocyanide complexes of nickel, NiBr2(CNAr)(2), are found to be active catalysts for polymerization of ethylene in the presence of methylaluminoxane (MAO). The catalytic activity and properties of polyethylene formed vary with substituents on the aryl group, in particular, at the 2- or 2,6-positions. The nickel complexes having 2,6-diphenylphenylisocyanide and its analogues are catalysts showing moderate activity and giving high molecular weight polyethylene (M-v > 10(6)), whereas those bearing 2-phenylphenylisocyanide and its analogues give polyethylene with M-w = 10(3)-10(4).