The effect of grafting monomer charge on the antifouling performance of poly(ether ether ketone) hollow fiber membrane by ultraviolet irradiation polymerization

To improve the antifouling properties of poly(ether ether ketone) (PEEK) membrane, negatively charged acrylic acid (AA), neutral ethyl hydroxyacrylate (HEA) and positively charged acryloxyethyl trimethylammonium chloride (DAC) as hydrophilic monomers were respectively grafted onto the PEEK hollow fiber membrane surface via ultraviolet irradiation polymerization. The effects of the grafted monomers on surface chemical structure, surface morphology, zeta potential, hydrophilic performance, permeability and the antifouling properties of the membrane were investigated in detail. The results show that the charge state of the membrane surface is closer to the monomer charge characteristic, which obviously affects the permeability and antifouling performance of the membrane. The pure water flux of the membrane grafted with neutral hydrophilic HEA monomer is increased and the antifouling properties to bovine serum albumin (BSA) and sodium alginate (SA) are also enhanced, while the pure water flux of the membranes grafted with negatively charged AA monomer or positively charged DAC monomer is decreased, with different antifouling properties to BSA and SA. Furthermore, the antifouling experiment with BSA under different pH conditions revealed that membrane fouling depends on the pH value, and membrane fouling was the most serious at the isoelectric point of BSA. © 2020 Society of Chemical Industry PEEK hollow fiber membranes were modified with three different charged monomers, and their surface charge plays an important role in antifouling performance.