Comparative study on oxidative and enzyme catalyzed oxidative polymerization of aminophenol compound containing dihalogen

Abstract

Properties of polymers were obtained by enzyme catalyzed oxidative polymerization varies according to oxidative polymerization products and thus polymeric materials with diferent properties are obtained. In this study, polymerization of 4-amino2,6-dichlorophenol (ADCP), an aminophenol compound containing dihalogen, was carried out by two diferent methods and the two methods were compared with each other. One of the methods was oxidative polymerization in the presence of hydrogen peroxide with heating, and the other was enzyme-catalyzed oxidative polymerization that took place at room temperature in the presence of Horse Radish Peroxidase (HRP) enzyme and hydrogen peroxide. The structural characterization of the products obtained as a result of oxidative polymerization (PADCP-O) and as a result of enzyme catalyzed oxidative polymerization (PADCP-E) was performed by 1 H-NMR, 13C-NMR, FT-IR, UV–Vis spectroscopy methods. The molecular masses of PADCP-O and PADCP-E were analyzed by GPC and the average molecular mass of PADCP-E was found to be higher than that of PADCP-O. Thermal properties were examined by TGA and it was determined that the thermal stability of the obtained polymers was higher than that of the monomer. Electrochemical and optical properties were determined by CV and UV–Vis spectroscopy methods, respectively. Electrochemical and optical band gap values were calculated as 1.61 and 1.33 eV, and 1.88 and 1.83 eV for PADCP-O and PADCP-E, respectively. In addition, it was observed that PADCP-O emitted green in UV light, while PADCP-E emitted red in DMSO. Surface properties and morphology of polymers were analyzed by SEM and it was observed that PADCP-O obtained by oxidative polymerization had a spongy structure, but the enzymatic polymerization product PADCP-E had a uniformly dispersed nanoparticle structure.