The radiation‐induced graft copolymerization of methacrylic acid with polyethylene. Ion‐exchange properties of the copolymeric composites

The study involves the preparation and characterization of a series of polyethylene‐g‐comethacrylic acid polymers in which the comonomer provides a degree of hydrophilicity to the backbone polymer. Such copolymers have been shown to possess efficient ion‐exchange properties with respect to Fe(III) ions, used as a model for general exchange. As such, we have a useful extension to our work on enzyme immobilization and protein separations using this type of support. Grafting was carried out in air and under vacuum. A correlation between the carboxylic acid group content and the extent of grafting was found. Under the conditions employed in our experiments, a maximum in grafting levels was observed when water was used as a continuous medium but not when methanol was included in the solvent assembly. No significant difference was observed between grafting carried out in air and that carried out under vacuum, when aqueous solutions of methacrylic acid were used. The graft copolymers have been shown to be effective in isolating Fe(III) ions and to be amenable to recycling procedures.