Synthesis and modification of poly(ethyl 2-(imidazol-1-yl)acrylate) (PEImA)

We present the synthesis and characterization of poly(ethyl 2-(imidazol-1-yl)acrylate) (PEImA) using free radical polymerization in various solvents with and without acids as additive. In addition, PEImA was also prepared using anionic polymerization with KOtBu as initiator in DMF and in THF at different M:I ratios. The resulting polymers of moderate dispersity were characterized by 1H-NMR, solid state 13C-NMR, and size exclusion chromatography (SEC) both in water and DMAc. PEImA is an interesting highly substituted polymer as it can be modified by methylation to poly(ethyl 2-(methyl imidazolium-1-yl iodide)acrylate) PEMeImA, via ester cleavage into the polyzwitterion poly(2-(imidazol-1-yl)acrylic acid) (PImAA), and – finally - to poly(2-(methyl imidazolium-1-yl)acrylic acid) (PMeImAA) if both modification steps are carried out. We also investigated structure and solubility of these different polyelectrolytes using potentiometric titration in aqueous media.