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A bulk, template-free method to synthesize nanofibers of substituted polyanilines is presented. The morphology of the substituted polyanilines changes from agglomerates or micron-sized spheres to a nanofiber network when an initiator, such as p-phenylenediamine, is introduced into the conventional reagents used to synthesize these polymers. UV-vis spectroscopy and cyclic voltammetry reveal that the oxidation state and chemical composition of the substituted polyaniline nanofibers do not differ significantly from that of conventional polyaniline derivatives possessing an agglomerated morphology. Gel permeation chromatography indicates that the nanofibers formed possess an unusually low polydispersity compared to substituted polyanilines synthesized by other methods. Open-circuit potential measurements obtained during the synthesis of these polyaniline derivatives confirm that there is a significant increase in the reaction rate of the polymerization which is directly related to nanofiber formation. This synthetic method appears quite general as a wide variety of substituted aniline monomers have been polymerized into nanofibrillar polymers.

The electropolymerization of o-methoxyaniline in the presence of (+)-(1S)-or (-)-(1R)camphorsulfonic (HCSA) provides a route to optically active poly(o-methoxyaniline) (POMA). The green emeraldine salt films POMA‚(+)-HCSA (1a) and POMA‚(-)-HCSA (1b) deposited on ITO-coated glass working electrodes exhibit mirror imaged circular dichroism spectra in the visible region, indicating diastereoselection in the electrochemical deposition. Their chiroptical properties suggest that these POMA‚ HCSA salts adopt a "compact coil" conformation for their polymer chains. The films are readily soluble in a range of organic solvents, retaining their optical activity and "compact coil" conformations. A strong red shift in the position of the low energy polaron band of 1a along the solvent series NMP < CHCl 3 < DMSO, DMF < MeOH indicates a concomitant increase in the conjugation length of the polymer chains. The 1a and 1b films may also be dedoped in aqueous 1.0 mol dm -3 NH4OH to give optically active POMA emeraldine base. Redoping of these latter blue films with 1.0 mol dm -3 HCl regenerates the circular dichroism spectra of the original 1a and 1b films, confirming retention of configuration during reversible dedoping/redoping cycles in the solid state.

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