Synthesis, FTIR, solid-state NMR and SEM studies of novel polyampholytes or polyelectrolytes obtained from EGDE, MAA and imidazoles

Novel materials with either polyampholyte or polyelectrolyte character and coordination properties were obtained by reaction of methacrylic acid (MAA), imidazole (IM) or 2-methylimidazole (2MI) and ethylene glycol diglycidyl ether (EGDE) in the presence of benzoyl peroxide. This new synthetic strategy gave rise to non-soluble, compact plastics that can be milled into non-porous particles. The polymers were studied by solid-state 13C NMR spectroscopy, FT IR and scanning electron microscopy (SEM). The experimental values of the isoelectric point (pI) were 6.04 ± 0.02 for poly(EGDE–MAA–IM) and 6.4 ± 0.2 for poly(EGDE–MAA–2MI). The water content was low due to the high cross-linking degree. These materials behaved as ionic exchangers. Copper (Cu2+) was chosen as a model, the equilibrium binding was analyzed, and the coordination properties were studied by FTIR and scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDS). The maximum binding capacity for copper ion was 67 mg g−1 for poly(EGDE–MAA–IM), 57 mg g−1 for poly(EGDE–MAA–2MI) and 0.9 mg g−1 for poly(EGDE–MAA).