The electrochemical copolymerization of aniline and N

N

N'-trimethylthionin (azure B) in aqueous solutions hasbeen carried out using the potential sweep method

The optimum conditions for the coelectrodeposition are that the pH valueand the temperature of the electrolytic solution are controlled at 5.57 and 30℃

respectively

and the scan potential range isset between - 0.25 and 1.10 V (versus SCE). The copolymerization rate of aniline and azure B is about 3 times larger thanthat of aniline in the absence of azure B.The copolymerization of aniline and azure B was verified from the results of visible spectra during electrolysis

FTIR spectra and the atomic force microscopy (AFM) images of the polymers.The in situ visible spectrum for the electrolysis of the solution containing aniline and azure B is different from that of the respective aniline and azure B.The FTIR spectrum of the copolymer is not a superposition of that of polyaniline and poly(azure B).The AFM image of the copolymer is different from those of polyaniline and poly(azure B)and is not a mixture of individual polymers.The conductivity of the copolymer synthesized at pH 5.57 is four orders od magnitude higher than that of polyaniline synthesized under the same conditions

but in the absence of azure B.The electrochemical properties of the copolymer are mainly attributed to polyaniline

but the copolymer has a better electrochemical reversibility and a much faster charge transfer than those of polyaniline.