Controlled Polymerization in Polar Solvents to Ultrahigh Molecular Weight Polyethylene.

Novel complexes based on 2,4,8-triarylnaphthylamine [[(2,4-{3,5-(CF3)2C6H3}2-8-(3,5-R2C6H3)-C10H4)-N═C(H)-{3-(9-anthryl)-2-O-C6H3}-κ2-N,O]Ni(CH3)(pyridine)] (4-Py, R = Me; 5-Py, R = CF3) were synthesized from 8-arylnaphthylamines which can be generated via selective lithiation, borylation, and coupling in a one-pot procedure. Due to their living characteristics in ethylene polymerization and the particularly low propensity of 5-Py for β-H elimination as reflected by a high linearity even at elevated polymerization temperatures of 60 °C, ultrahigh molecular weight polyethylene (UHMWPE) is formed in polar organic solvents (THF, diethyl ether) as a reaction medium in a controlled polymerization ( Mw/ Mn = 1.2 at Mn = 1.1 × 106 g mol-1).