The studied polymers (chelate modified polysulfones) have been prepared by the polycondensation reaction between chloro-end-capped polysulfones and bis(2,4-dihydroxybenzaldehyde)Cu2+ in the dymethyl sulfoxide/dichlormethane system, in the presence of an aqueous sodium hydroxide solution. The temperature dependence of electrical conductivity and Seebeck coefficient of the respective polymers was investigated using thin-film samples, deposited from chloroform solutions onto glass substrates. The polymers under study have typical semiconducting properties. The values of some characteristic parameters of the investigated polymers (for example, activation energy of electrical conduction, ratio of carrier mobilities, etc.) have been determined. The nature of the electrical conduction mechanism is discussed. The values of the optical bandgap energy are determined from the absorption spectra. (c) 2005 Wiley Periodicals, Inc.