Process for radiation grafting hydrogels onto organic polymeric substrates

A method is described for radiation grafting hydrogels onto an organic substrate by incorporating an effective amount of cupric or ferric ions at a concentration in the range of from 0.0008M to 0.0016M in an aqueous graft solution consisting of N-vinyl-2-pyrrolidone (N-VP) monomer or mixtures of N-vinyl-2-pyrrolidone and a second monomer selected from the group consisting of 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, propylene glycol acrylate, acrylamide, methacrylic acid and methacrylamide, immersing the organic substrate in the aqueous monomer graft solution and thereafter subjecting the contacted substrate to ionizing radiation