Wang Aqiang, Zhu Yuzhang, Fang Wangxi, Gao Shoujian, Jin Jian
College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, 215123, P. R. China.
i-Lab, CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, P. R. China.
Small Methods. 2024 Apr;8(4):e2300247. doi: 10.1002/smtd.202300247. Epub 2023 Jun 25.
Current hydrophilic modification strategies improve the antifouling ability of membranes but fail to completely eliminate the fouling of emulsified oil droplets with a wide size distribution. Constructing membranes with superior anti-oil-fouling ability to resist various oil droplets especially at high permeation fluxes is challenging. Here, the fabrication of a zero-oil-fouling membrane by grafting considerably high coverage of zwitterionic polymer and building defect-free hydration defense barrier on the surface is reported. A uniform layer of protocatechuic acid with COOH as abundant as existing in every molecule is stably deposited on the membrane so as to provide sufficient reactive sites and achieve dense grafting of the zwitterionic polymer. The coverage of zwitterionic polymer on the membrane plays a crucial role in promoting the antifouling ability to emulsified oil droplets. The poly(vinylidene fluoride) membrane with 93% coverage of the zwitterionic polymer exhibits zero oil fouling when separating multitudinous oil-in-water emulsions with ≈0% flux decline, ≈100% flux recovery, and a high water flux of ≈800 L m h bar. This membrane outperforms almost all of the reported membranes in terms of the comprehensive antifouling performance. This work provides a feasible route for manufacturing super-antifouling membranes toward oil/water separation application.
当前的亲水化改性策略提高了膜的抗污染能力，但未能完全消除宽尺寸分布的乳化油滴的污染。构建具有优异抗油污染能力以抵抗各种油滴的膜，尤其是在高通量下，具有挑战性。在此，报道了通过接枝相当高覆盖率的两性离子聚合物并在表面构建无缺陷的水合防御屏障来制备零油污染膜。一层每分子中羧基含量丰富的原儿茶酸均匀地沉积在膜上，以提供足够的反应位点并实现两性离子聚合物的致密接枝。膜上两性离子聚合物的覆盖率在提高对乳化油滴的抗污染能力方面起着关键作用。两性离子聚合物覆盖率为93%的聚偏氟乙烯膜在分离众多水包油乳液时表现出零油污染，通量下降约0%，通量回收率约100%，水通量高达约800 L m⁻² h⁻¹ bar⁻¹。就综合抗污染性能而言，该膜几乎优于所有已报道的膜。这项工作为制造用于油/水分离应用的超抗污染膜提供了一条可行的途径。
