Studies on the chemical syntheses and on the characteristics of polyaniline derivatives

Syntheses of parent polyaniline and methyl, methoxy, and ethoxy ortho‐substituted polyanilines were performed using the conventional chemical methodology and monitored using the new open‐circuit‐potential ( V oc ) profile technique. The intermediate pernigraniline oxidation state was identified and isolated at the V oc maximum ( A ) during the conventional chemical synthesis of poly( o ‐methoxyaniline) in the emeraldine oxidation state. The introduction of the substituent on the aniline ring leads to longer polymerization times and lower V oc values. Syntheses in the presence of two different monomers in solution were also investigated and showed preferential polymerization of the monomer with the lowest V oc potential. All polymers produced were characterized by elemental analysis, gel permeation chromatography, UV‐VIS spectroscopy, and cyclic voltammetry. The influence of the substituent on the V oc profile and on the polymer characteristics are rationalized in terms of steric and electronic effects.