Direct Chemical Oxidative Polymerization of Polymelamine and its Copolymerization with Aniline for Hydrogel Supercapacitor Electrodes

In this work, we report for the first time, the direct chemical oxidative polymerization of melamine (MA) to obtain polymelamine (PME) via the initiation of a common oxidant, ammonium peroxydisulfate (APS). Characterizations of MA and PME were carried out by SEM, FTIR, XPS, NMR, and TGA measurements, and the results were compared with those from published works to verify the successful synthesis of PME. The PME was further used to initiate aniline (ANI) monomers, and an emeraldine product, called PAMx, was interestingly afforded. Moreover, APS oxidant was added into the solution as a second initiator for the polymerization of the residual monomers and remaining reactive sites on PAMx, thereby directly forming the hydrogel electrode, and labeled as PAMxS. The electrochemical performances of the PANI and PAMxS hydrogel supercapacitor electrodes were compared, and a high specific capacitance of 568 F g−1 at scan rate of 2 mV s−1 was obtained for PAM6S compared with 371 F g−1 for PANI. The facile direct oxidative synthesis approach for the preparation of PME provides an efficient route for its mass production, and its initiation ability with ANI monomers holds interesting potentials for the construction of macromolecules in conductive polymer applications.