Electrochemical copolymerization study of o-toluidine and o-aminophenol by the simultaneous EQCM and in situ FTIR spectroelectrochemistry.

The electrochemical synthesis and characterization of a copolymer, poly(o-toluidine-co-o-aminophenol), were conducted using in situ piezoelectric FTIR spectroelectrochemistry. The monomer feed ratio strongly affects the copolymerization rate and the properties of the copolymer during the electrosynthesis in 0.5M H(2)SO(4) aqueous solution. The effects of scan rate and pH value on the electrochemical activity of the obtained copolymer were also studied. The copolymer synthesized in higher molar ratio of o-toluidine/o-aminophenol exhibited good electrical activity and stability in a broad pH range. The copolymerization mechanisms of o-toluidine and o-aminophenol were deduced. The copolymer formed through the head-to-tail coupling of the two monomers via -NH- groups was a new polymer rather than a mixture of poly(o-toluidine) and poly(o-aminophenol).