Simple temperature-regulated polymerization for fabrication of tea polyphenols modified PVDF membrane toward emulsion separation

Abstract

Surface modification of membranes through facile coating methods is a promising way to improve their pollution resistance and separation performance. Here, a tea polyphenols (TP) coated PVDF membrane (PVDF-TP) was prepared via simple temperature-regulated oxidative polymerization. The obtained membrane exhibited water contact angle of 0° and underwater oil contact angle of 168.2°. This superhydrophilic/underwater superoleophobic membrane showed good separation capabilities with fluxes of 88.3-169.9 L m-2 h-1 and separation efficiencies of over 98.7% various oil-in-water emulsions under gravity-driven. The PVDF-TP membrane exhibited excellent stability and is capable of withstanding ultrasonic waves, bending, and agitation. Even recycled for more than 15 times, the separation efficiency of membrane is still above 98.7% and the flux decreased by approximately 37%, demonstrated the well anti-fouling performance. Considering the characteristics of simple preparation, good antifouling performance, high separation efficiency, and good stability, PVDF-TP membrane has a broad application prospect in the field of oil-water separation.