Synthesis and preliminary evaluation of chelating resins containing α-aminoalkylphosphonic groups

Chelating polymers containing an α-aminobenzylphosphonic acid group or an α-aminopyridylphosphonic acid group have been prepared starting with a crosslinked polyaminomethylstyrene. Chemical modification was achieved via the addition of diethyl phosphonate followed by hydrolysis (Kabachnick-Fields reaction) or by the addition of phosphorous acid onto the corresponding polyimines. Preliminary evaluation of the sorption capacities towards Ca²⁺ and Co²⁺ have shown that the prepared polymers exhibit similar or slightly greater chelating properties than a commercial resin (Duolite ES 467). It was also found that polymers containing an α-aminopyridylphosphonic acid group displayed a significant affinity towards Co²⁺ contrary to resins containing an α-aminobenzylphosphonic acid group.