Synthesis and Properties of Polymers Containing 2H-Benzimidazol-2-one Moieties: Polymerization via N-C Coupling Reactions.

Novel homopolymers and copolymers containing 2H-benzimidazol-2-one units have been synthesized by N-C coupling reactions of 1H-benzo[d]imidazol-2(3H)-one and activated aromatic dihalides under conditions similar to those for the synthesis of poly(aryl ether)s and poly(benzimidazole sulfone)s. 1H-Benzo[d]imidazol-2(3H)-one behaved like a bisphenol in the polymerization reaction to afford, quantitatively, high molecular weight linear polymers with inherent viscosities (ηinh) ranging from 0.57 to 1.31 dL/g. The polymers were soluble in various organic solvents, and transparent, flexible, and creasable films were cast from its dichloromethane-solution. The homopolymer had a remarkably high glass transition temperature (Tg 348 °C) and good thermal stability. Only 30 mol % (8.9 wt %) of the 2H-benzimidazol-2-one unit for the copolymer with 4,4'-biphenol was required to raise the Tg of commercial poly(aryl ether), Radel R-5000 from 220 to 269 °C.