Conducting polyaniline (PANI) is a promising material for various technological applications, including the creation of biosensors, protective coatings as electrode materials for supercapacitors and other areas. The most popular method of PANI synthesis is chemical oxidative polymerization. But this method is far for from being environmentally friendly, as it requires strong acidic media and large amounts of the oxidant. It can also lead to the formation of toxic by-products such as benzidine. The enzymatic synthesis of PANI is an alternative to chemical polymerization and considerably meets the requirements of green and sustainable chemistry. Enzymatic reactions proceed under ‘mild’ operating conditions, at pH values close to neutral, and in the absence of toxic organic solvents. In this work a comparative study of the template-assisted enzymatic and chemical polymerization of aniline in a buffer solution of sodium dodecylbenzenesulfonate (SDBS) micelles was performed. The high-redox potential laccase from the fungus Trametes hirsuta was used as a catalyst and air oxygen served as an oxidant. Potentiometric and spectral methods have shown that oligomeric/polymeric products of the enzymatic polymerization of aniline are synthesized in the conducting emeraldine salt form immediately after the reaction is initiated by the enzyme. The enzymatic polymerization of the monomer was greatly accelerated, and the yield of the resulting products (PANI/SDBS complexes) was increased through the use of the redox mediator potassium octocyanomolybdate (IV). The products of the enzymatic polymerization of aniline were studied by the ATR-FTIR, MALDI-TOF and atomic force microscopy methods. Compared to the enzymatic polymerization, the end product of the chemical aniline polymerization performed under the same conditions was dark brown and non-conducting. The conducting PANI/SDBS complexes were tested as protective coatings. They demonstrated a high inhibition efficiency of copper corrosion and high antistatic properties. The efficiency of the inhibition of copper corrosion by the complexes in aqueous 1 M HCL was 86–87%, and the dissipation rate of positive and negative charges from cotton fabrics increased by 56 and 27 times, respectively.

Conflicts of interest:
The authors declare that they have no conflict of interest in the publication of this article. The authors have no conflicts of interest to report in this work. Abstract was not submitted elsewhere and was first published here.

Funding:
This study was supported in part by Lomonosov MSU Reg. Theme 121041500039-8.