Radiation synthesis and characterization of polyamidoamine dendrimer macromolecules with different loads of nickel salt for adsorption of some metal ion

Graft copolymer networks of poly(methacrylic acid-g-polyamidoamine dendrimer) with different loads of nickel salt were synthesized by gamma radiation-induced copolymerization of polyamidoamine dendrimer and methacrylic acid (MAA). Nickel release and metal adsorption from the polymeric systems, and their thermal stability were analyzed. A high percentage of the nickel loaded was released, although strong interactions between the polymeric matrices and the nickel ion was established since a total nickel release did not take place. The higher the concentration of the loading Ni^{2 +}, the higher were the adsorption capacities obtained. The metal release and uptake by such prepared hydrogels was determined by using atomic absorption technique. On the other hand, the presence of nickel salt induced an evident thermal instability in the polymeric matrices, although all the polymeric systems can be considered thermally stable.