Poly(4-aminobiphenyl): chemical synthesis, characterization studies and comparison with conductive electropolymerized samples

Poly(4-aminobiphenyl) synthesized both chemically and electrochemically were examined and compared by UV, FT-IR, X-ray photoelectron spectroscopy, thermogravimetry and differential scanning calorimetry. Results indicate that, in chemically synthesized samples, protonation of the nitrogen atoms occurs with chloride as the major counter ion, whilst, in the electropolymerized sample, concurrent oxidation of the biphenyl backbone was also observed. Conductivities of the electropolymerized and chemically synthesized polymers doped with FeCl3 are 0.02 and 10−6 S cm−1, respectively. In addition, the chemically synthesized polymer in its base form is found to be dopable with iodine to a conductivity of 2 × 10−4 S cm−1. Scanning electron microscopy indicates a fibrous structure for the electropolymerized sample in contrast to the chemically synthesized form which has a granular to globular morphology, with the granules themselves made up of a fine network of fibrils.