A effective approach for surface modification of polymer membrane via SI-eATRP in an electrochemical cell with a three electrode system

In this study, an environmentally friendly approach for surface modification of polymer membrane was reported, which named surface-initiated electrochemically mediated atom transfer radical polymerization (SI-eATRP). It was triggered after diffusion of a CuI/L activator generated at a working electrode. The introduction of electrochemically mediation can control the polymerization of monomers by a one-electron reduction of an initially added air-stable CuII salt. The reaction was carried out in an electrochemical cell with a three-electrode system at low temperature. Using this technique, hydrophilic polymer brushes of poly(N-vinylpyrrolidone) were grafted onto PES membrane surface. The effects of reaction conditions like polymerization time, monomer concentration, initiator amount, and different monomer on the polymerizations of monomer were investigated in detail. Based on these data, we concluded that the polymerization on polymer membrane surface could be controlled by mediating the reaction condition. Moreover, the precisely controlled polymerization may allow it to serve as excellent model systems for polymer membrane modification, in general, to illustrate the role of electrochemically mediating on the polymerization approach. And the water contact angle of the modified membrane decreased from 89° to 72°. The APTT of the modified membrane increased from 46 s to 81 s. Those results indicated that the surface modification by grafting PVP brushes provided practical application for the PES membranes with high surface properties.