Ring-opening reaction of poly-GMA chain grafted onto a porous membrane

An epoxy-group-containing polymer chain was grafted onto a porous polyethylene membrane of hollow-fiber form by applying radiation-induced graft polymerization. The produced epoxide was converted into a diol group, ion-exchange (diethylamino and sulfonic acid) and chelate-forming (ethylenediamine and iminodiacetic acid) groups, and pseudoaffinity ligands (phenylalanine and tryptophan). The conversion of the epoxide into the functional group was investigated as a function of the degree of GMA grafting and molecular weight of the reactants. A reactant with low molecular weight exhibited a high conversion. The high conversion of the epoxide into the ion-exchange group caused the extension of the polymer chain grafted onto the pore interface and decreased the water permeability through the hollow-fiber membrane.