Sequestration of Trace Metals Using Water-Soluble and Fluorous Phase-Soluble Polymers

Abstract

Ion-exchange polymers with “on”/“off” solubility can be prepared from N-isopropylacrylamide (PNIPAM) copolymers that incorporate hydroxamic acid ligands. Such complexing agents quantitatively remove trace amounts of FeIII from aqueous solutions (vial 1) by precipitating the metal – polymer complex on heating (suspension in vial 2). Physical separation of the insoluble polymer leaves a metal-free solution (vial 3). Similar fluorous phase-soluble hydroxamic acid derivatives of fluoroacrylate polymers remove FeIII ions from organic solutions by liquid/liquid phase separation.