Grafting of poly(vinyl pyrrolidone) with citric acid using gamma irradiation

Ternary mixtures of poly(vinyl pyrrolidone) (PVP), citric acid (CA) and water were irradiated at various gamma ray doses. Copolymer swelling and gelation% were determined with respect to the irradiation dose and PVP/CA composition. The gelation% increases with increasing the irradiation dose, but decreases with increasing the CA content in the graft copolymer. The swelling% of the prepared hydrogels decreases with increasing the irradiation dose and CA content in the copolymer, as a result of an increase in the crosslink density and the hydrogen bonds, respectively. The ion exchange capacity and the uptake of uranyl ions increase with increasing the CA content in the graft copolymer.