Functional amphiphilic polyorganophosphazenes as macromolecular chelators in aqueous actinide solutions

This study evaluated several ligands targeted for polymer-based separations of aqueous actinide wastes. Polyphosphazenes are ideal for assessing specific chelating moieties since synthetic methods enable precise control of polymer composition. Furthermore, polyphosphazenes or polyphosphazene grafts are well-suited for many diverse treatment processes since they may have many different forms (water-soluble polymers, membranes, resins, or foams). A series of water-soluble polyphosphazenes were synthesized with a fraction of the sidegroups terminated by different chelating moieties. The chelating moieties were chosen after evaluation of analogous small molecule and polymer-bound actinide ligands. The distribution coefficients of U, Pu, and Am species were evaluated for aqueous solutions (HNO3/NaNo3, pH = 1 to 8) of the newly synthesized chelating polymers