Synthesis and electrochemical studies of new styrenic poly(ionic liquid)s based on the 1-methyl-1,2,3-benzotriazolium cation

Abstract

The styrenic ionic liquid-based poly ionic liquids (PILs) with the advantage of facile synthesis and the ability to incorporate many desirable functional moieties offer an efficient route to highly functional styrenic PILs. On the other hand, triazole is a desirable and useful heterocyclic compound that can be used in various fields of polymer and material science to attain better properties. In this paper, a set of new styrenic ionic liquid monomers based on 1-methyl-1,2,3-benzotriazolium cation were successfully synthesized by a quaternization of 1-methyl-1,2,3-benzotriazole with 4-vinylbenzylchroride. Subsequently, an anion exchange reaction was carried out. Afterward, these styrenic ionic liquid monomers readily polymerized via free radical polymerization. The chemical structures of these monomers and polymers were confirmed by Fourier transform infrared spectroscopy and proton and carbon nuclear magnetic resonance (1H- and 13C-NMR). Furthermore, the solubility of the homopolymers in different solvents was tested. The thermal behavior of the polymers was evaluated by thermogravimetric analysis and differential scanning calorimetry. The cyclic voltammetery measurements revealed that these polymers have a larger electrochemical window compared with polystyrene.