Biocatalyzed synthesis of conducting polyaniline in reverse microemulsions

A green and efficient reaction system containing hydrogen peroxide and hemoglobin in dodecylbenzenesulfonic acid (DBSA) reverse microemulsions was developed for the polymerization of aniline. The effect of water content (Wo), reaction time, concentrations of DBSA, aniline and H2O2 were carefully examined. It was found that the conductivity of polyaniline (PANI) changed with the water content. The highest conductivity of 0.90 S/cm was obtained when Wo was 22.5. UV–vis spectra, Fourier transform infrared and X-ray diffraction spectra indicated the formation of conducting PANI doped with DBSA. The DBSA-doped PANI was nanoscaled, furcate shape according to scanning electron microscopy and transmission electron microscopy. From thermogravimetric analysis, it was found the product was obtained with excellent thermal stability. In comparison with other enzymatic polymerization systems, the new system gave higher reaction efficiency, higher conductivity and thermal stability of PANI.