Flexible brown films of polyparaphenylene (PPP) with fibrous morphology were obtained by electro-oxidation of benzene on an indium tin oxide (ITO) electrode at a constant potential between +1.8 and +3.0 V/SCE using CuCl+AlCl3, in nitrobenzene. The morphology of the PPP film depended on the applied potential, the electrode, the electrolyte and the solvent. This procedure was also applicable to the electropolymerization of toluene, p-xylene, diphenyl ether and naphthalene, but no fibrous morphology was observed. The electrical conductivities of the PPP and polynaphthalene (PN) films were ca. 10(-3) S cm(-1) and 10(-4) S cm(-1) respectively after Li+ doping. The decomposition temperatures T-d of the PPP, PN and poly(oxy-3,3’-biphenylene) films were 511 degrees C, 546 degrees C and 486 degrees C respectively. The fairly high T-d of the PN film was due to its rather high degree of polymerization.