Shandong Key Laboratory of Oilfield Chemistry, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China; Key Laboratory of Unconventional Oil & Gas Development, China Universcity of Petroleum (East China), Ministry of Education, Qingdao 266580, China.
Shandong Key Laboratory of Oilfield Chemistry, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China; Key Laboratory of Unconventional Oil & Gas Development, China Universcity of Petroleum (East China), Ministry of Education, Qingdao 266580, China.
J Colloid Interface Sci. 2022 Feb 15;608(Pt 1):702-710. doi: 10.1016/j.jcis.2021.09.123. Epub 2021 Sep 29.
Superhydrophilic/underwater superoleophobic membrane constructed by hydrophilic polymers possesses great advantage in the separation of oily waste water, due to its intrinsic oil-repellent property. The formation of hydration layer to repel and block oil is considered as the mechanism of underwater superoleophobicity and subsequent oil/water separation. Constructing a stable hydrophilic polymer network on the substrate surface would significantly improve the robustness of hydration layer.
In this work, a feasible and universal mussel-inspired dip-coating method was developed for constructing stable hydrophilic polymer network onto target substrate surface, via successively immersing substrate membranes into aqueous solutions of polydopamine (PDA) and catechol-functionalized hydrophilic polymer (CFHP). After pre-wetting with water, the polymer network would swell with water to form a thin and stable water film layer, serving as a barrier against oil penetration.
The as-prepared CFHP/PDA modified membranes exhibit outstanding performance in separating various oil/water mixtures and oil-in-water emulsions stabilized by surfactants, with separation flux up to 5641.1 L·m·h and separation efficiency achieving 99.98%. The surface modification method developed in this work can be easily extended to various materials and membrane systems, for achieving a variety of practical applications such as industrial wastewater treatment.
由亲水聚合物构建的超亲水/水下超疏油膜由于其内在的疏油性，在分离含油废水方面具有很大的优势。水合层的形成排斥和阻挡油被认为是水下超疏油性和随后的油水分离的机制。在基底表面上构建稳定的亲水聚合物网络将显著提高水合层的稳定性。
在这项工作中，通过将基底膜依次浸入聚多巴胺（PDA）和儿茶酚功能化亲水聚合物（CFHP）的水溶液中，开发了一种可行且通用的贻贝启发式浸涂方法，以在目标基底表面上构建稳定的亲水聚合物网络。用预润湿水后，聚合物网络会吸水膨胀形成薄而稳定的水膜层，作为阻止油渗透的屏障。
所制备的 CFHP/PDA 改性膜在分离各种油/水混合物和由表面活性剂稳定的油包水乳液方面表现出优异的性能，分离通量高达 5641.1 L·m·h，分离效率达到 99.98%。本工作中开发的表面改性方法可以很容易地扩展到各种材料和膜系统，以实现各种实际应用，如工业废水处理。
