Successful synthesis of wholly aromatic polyketones via nickel-mediated aromatic coupling polymerization

Novel aromatic polyketones (8a, 8b);without ether linkage in the main chain were successfully synthesized via nickel-mediated aromatic coupling polyme rization of bis(chlorobenzoyl)dimethoxybiphenyls (3a, 3b). The polymers aff ording flexible films were obtained in the reaction where an excess amount of bipyridyl and a stoichiometric amount of the nickel(II) bromide were pre sent. The resulting polyketones (8a, 8b) have sufficiently high molecular w eight (inherent viscosity: 0.59 dL/g for polyketone 8a; 0.35 dL/g for polyk etone 8b) and a highly amorphous nature with a rather high glass transition temperature: 218 degreesC for polyketone 8a; 192 degreesC for polyketone 8 b.