Laccase-catalyzed homo-polymer of GAL and cross-linking with PEI to enhance hydrophilicity and antifouling property of PTFE flat membrane

Abstract To improve hydrophility and antifouling property of Polytetrafluoroethylene flat microfiltration membrane, a novel and facile method was developed to modify the membrane via the polymer of Laccase-catalyzed self-polymerization of Gallic acid and cross-linked with Polyethylenimine, then the surface micro/nanostructures was treated by (2,3-epoxypropoxy)-propytrimethoxysilane. The surface chemical composition, surface morphology, hydrophilicity and antifouling property of the PTFE flat membrane were investigated by ATR-FTIR, XPS, FESEM, water contact angle, pure water flux measurements, respectively. After using this low-cost and simple modification method, PTFE flat membranes were endowed with excellent hydrophilicity, high pure water flux and antifouling property. Besides, the modified PTFE flat membrane could be applied to the separation of oil-in-water emulsion with an ultrahigh efficiency 98.2% and also shows durable oil resistance and antifouling performance, making the membrane easy to reuse. Finally, the surface stability of the modified membrane was studied and the mineralized membrane showed excellent acid resistant ability. Therefore, this facile strategy holds attractive potential practical application in water environmental remediation.