A highly active Ni(II)-triadamantylphosphine catalyst for ultrahigh-molecular-weight polyethylene synthesis.

Here we report that the tri-1-adamantylphosphine-nickel complex [Ad3PNiBr3]-[Ad3PH]+ upon activation with an alkylaluminoxane catalyzes the polymerization of ethylene to ultrahigh-molecular-weight, nearly linear polyethylene (Mn up to 1.68 × 106 g mol-1) with initial activities reaching 3.7 million turnovers per h-1 at 10 °C. Copolymerizations of ethylene with α-olefins such as 1-hexene and 1-octadecene, as well as tert-butyldimethyl(dec-9-en-1-yloxy)silane give the corresponding copolymers with no decrease in activity.