Developing antifouling coatings is of both fundamental and practical significance, but challenging, for membrane separation of oil-in-water (O/W) emulsions with charged surfactants, which has been conventionally achieved through the short-range hydration interaction from hydrophilic membrane surfaces as a physical barrier. Herein, we report a mussel-inspired antifouling coating formed by carboxyl and quaternary ammonium moieties bearing adjustable surface charge property, employing tunable long-range electrostatic interaction to achieve adaptive antifouling performance in response to the varying electrical characteristic of emulsions. The surface force measurement results showed that modulating the surface electrical properties of the coatings through varying the solution pH could effectively alter their electrostatic interactions with emulsions from attraction to repulsion, in combination with hydrodynamic interactions, to enable emulsion repellence of the coatings. Such functional coatings were further applied on a PVDF membrane with an enhanced water permeability and reusability achieved to separate both the positively and negatively charged emulsions. By properly modulating the membrane surface charge, the modified membrane demonstrated its adaptive antifouling performance for efficient and universal water treatment. This work provides useful insights into the antifouling mechanisms of membranes to O/W emulsions, as well as developing functional materials with tunable surface interactions for various engineering applications.

开发带电表面活性剂的水包油（O / W）乳液膜分离的防污涂料具有基本和实际意义，但具有挑战性，这通常是通过亲水膜表面的短程水合作用来实现的。物理障碍。本文中，我们报告了一种由羧基和季铵基团形成的贻贝类防污涂料，该基团具有可调节的表面电荷性质，可响应于乳液的不同电学特性，采用可调节的远距离静电相互作用来实现自适应的防污性能。表面力测量结果表明，通过改变溶液的pH值来调节涂层的表面电性能，可以有效地改变其与乳液的静电相互作用，从吸引到排斥，再结合流体动力学相互作用，从而使涂层具有排斥乳液的能力。将这种功能性涂料进一步涂在PVDF膜上，具有增强的透水性和可重复使用性，可分离带正电和带负电的乳液。通过适当调节膜表面电荷，改性膜表现出了其对高效，通用水处理的适应性防污性能。这项工作为了解膜对O / W乳液的防污机理提供了有用的见识，