A comparison of laccase-catalyzed polymerization of aniline in the presence of two different “soft” templates - micelle forming surfactant sodium dodecylbenzenesulfonate (SDBS) and sulfonated natural polyelectrolyte calcium lignosulfonate (LGS) - was investigated to check the influences of different templates on the kinetics of the polymerization and on the characteristics of the complexes obtained. Under respective optimal conditions, pH 4.5 for SDBS and pH 3.5 for LGS, the reaction with LGS was much slower than that in SDBS emulsion. The conditions for laccase-catalyzed synthesis of emeraldine salt of polyaniline (PANI-ES) in both cases were optimized using UV-vis spectroscopy. It was found that PANI-ES obtained with LGS template had a higher degree of oxidation with a higher amount of benzene rings than PANI-ES obtained in SDBS emulsion. Since the protonation of PANI occurred on its imine sites, the doping effect of LGS-doped PANI-ES, confirmed by XPS, was thus better than that of SDBS-doped one.
Keywords: laccase-catalyzed polymerization, emeraldine salt of polyaniline, soft templates, sodium dodecylbenzenesulfonate, calcium lignosulfonate
2018; 42(2): 175-184
Published online Jan 25, 2018
Key Laboratory of Science and Technology of Eco-Textile, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China