Department of Chemical Engineering, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai 200240, P. R. China.
ACS Appl Mater Interfaces. 2015 Sep 9;7(35):19643-50. doi: 10.1021/acsami.5b04146. Epub 2015 Aug 25.
Wastewater contaminated with oil or organic compounds poses threats to the environment and humans. Efficient separation of oil and water are highly desired yet still challenging. This paper reports the fabrication of a smart fiber membrane by depositing pH-responsive copolymer fibers on a stainless steel mesh through electrospinning. The cost-effective precursor material poly(methyl methacrylate)-block-poly(4-vinylpyridine) (PMMA-b-P4VP) was synthesized using copper(0)-mediated reversible-deactivation radical polymerization. The pH-responsive P4VP and the underwater oleophilic/hydrophilic PMMA confer the as-prepared membrane with switchable surface wettability toward water and oil. The three-dimensional network structure of the fibers considerably strengthens the oil/water wetting property of the membrane, which is highly desirable in the separation of oil and water mixtures. The as-prepared fiber membrane accomplishes gravity-driven pH-controllable oil/water separations. Oil selectively passes through the membrane, whereas water remains at the initial state; after the membrane is wetted with acidic water (pH 3), a reverse separation is realized. Both separations are highly efficient, and the membrane also exhibits switchable wettability after numerous cycles of the separation process. This cost-effective and easily mass-produced smart fiber membrane with excellent oil-fouling repellency has significant potential in practical applications, such as water purification and oil recovery.
被油或有机化合物污染的废水对环境和人类构成威胁。高效分离油和水是人们非常期望但仍具有挑战性的目标。本文通过静电纺丝在不锈钢网上沉积 pH 响应性共聚物纤维，制备了一种智能纤维膜。使用铜(0)介导的可逆失活自由基聚合合成了具有成本效益的前驱体材料聚甲基丙烯酸甲酯-嵌段-聚(4-乙烯基吡啶)(PMMA-b-P4VP)。所制备的膜具有对水和油的可切换表面润湿性，这归因于其中 pH 响应性的 P4VP 和水下亲油性/亲水性的 PMMA。纤维的三维网络结构极大地增强了膜的油水润湿性能，这在油水混合物的分离中是非常理想的。所制备的纤维膜实现了重力驱动的 pH 可控的油水分离。油选择性地透过膜，而水保持初始状态; 在用酸性水(pH 3)润湿膜后，实现了反向分离。两种分离都非常高效，并且该膜在分离过程的多次循环后仍具有可切换的润湿性。这种具有成本效益且易于大规模生产的智能纤维膜具有出色的抗油污染能力，在水净化和采油等实际应用中具有重要的应用潜力。
