Poly (o-methoxy aniline): solubility, deprotonation-protonation process in solution and cast films

Solubility tests were performed at room temperature for poly (o-methoxyaniline) (POMA) inN,N-dimethylformamide (DMF), 1-methyl-2-pyrrolidone (NMP), m-cresol, acetonitrile, chloroform, dichloromethane and xylene, and compared with those for polyaniline. A reversible solvatochromic transition from green to blue was observed in dilute POMA solutions in DMF, NMP and m-cresol indicating the occurrence of deprotonation-protonation processes. The solvent NMP more readily induced deprotonation processes at higher concentrations than those observed in DMF solutions. On the other hand, m-cresol exhibited an ability to protonate POMA in solution regardless of its undoped or doped state. Ultraviolet-visible spectra confirmed modifications of electronic transitions in agreement with the color changes. Correlations among crystalline properties, electron paramagmetic resonance results and electric conductivity of POMA films processed from DMF, NMP and m-cresol solutions are discussed.