Soluble polypyrrole (PPy) samples advanced in electrical conductivity sigma were chemically synthesized with dodecylbenzenesulfonate (DBS) sodium salt as a dopant, with poly(ethylene glycol) (PEG) as an additive, and with ammonium persulfate as an oxidant. The PPy-DBS-PEG samples were soluble in organic solvents (N-methylpyrrolinone and m-cresol). The greater the molar percentage ratio was of DBS, the greater the solubility was of synthesized PPy composites (PPy-DBS-PEG). The maximum electrical conductivity at room temperature for PPy-DBS-PEG was 1.02 S/cm, which was in fact the true conductivity of 100/10 (mol %) PPy/DBS. The chemical composition and doping level of PPy-DBS-PEG were determined by elemental analysis. The results of Fourier transform infrared spectroscopy were used for the structural characterization of PPy-DBS-PEG. The scanning electron microscopy results showed that the electrical conductivity was related to the morphology of PPy-DBS-PEG. According to thermogravimetric analysis, PPy-DBS-PEG was more thermostable than PPy-DBS. Electron spin resonance measurements showed that the polaron and bipolaron acted as charge carriers of PPy-DBS-PEG. According to the temperature dependence of the electrical conductivity, PPy-DBS-PEG was a semiconductor and followed the three-dimensional variable-range hopping model. The improved electrical conductivity apparently resulted from the reduction of the crosslinking and structural defects of the PPy chains. (c) 2005 Wiley Periodicals, Inc.