Interaction of polyaniline with hydroxyl-ions in N-methylpyrrolidinone

Abstract

Interaction of emeraldine base (EB) of polyaniline (PANI) with tetraalkylammonium hydroxides (TAAHs) has been studied in N-methylpyrrolidinone solutions and complex films. The spectral changes in the solutions at the early stage of the interaction showed features typical of the increased intramolecular conductivity in PANI backbone, which has been assigned to a “pseudo” doping effect upon interaction of EB with TAAHs. Conductivity of films was found to also increase, however, intrinsic electronic conductivity of the films was completely masked by the ionic one. The above effect has been compared with that of the conventional inorganic base KOH in the same medium. It has been found that similar changes in electronic absorption spectra of EB take place within some range of concentrations of KOH in the mixture. The conclusion on strong interaction of EB and the above bases was supported by IR spectra of the complex films, which evidenced in favor of the chemical transformation of the polymer backbone. The final product was found to be unstable and degrades readily. Based on the above results the interaction of PANI and the bases used is discussed. A scheme of the possible PANI transformations is suggested.