Yu Ran, Pu Liying, Wang Xiaofang, Liu Peng, Shen Xiang
Yunnan Key Laboratory of Crystalline Porous Organic Functional Materials, College of Chemical and Materials Engineering, Qujing Normal University, Qujing 655011, China.
Langmuir. 2025 Aug 26;41(33):22316-22328. doi: 10.1021/acs.langmuir.5c02623. Epub 2025 Aug 16.
The eco-friendly nature and energy efficiency of polymeric membranes have established them as pivotal materials for oil-in-water emulsion separation. However, persistent membrane fouling caused by oil deposition remains a major challenge, significantly hindering their practical implementation in industrial settings. In this work, thiol-ene photochemistry was employed to synthesize PEGylated silica nanoparticles (SiO--PEGDA) using poly(ethylene glycol) diacrylate (PEGDA) and hexanedithiol (HD) as monomers. Biomimetic PVDF membranes were engineered via vapor-induced phase separation (VIPS) by integrating SiO--PEGDA nanoparticles, followed by secondary coagulation in a dopamine (DA) solution. The experimental results demonstrate that the biomimetic membranes exhibit a characteristic sponge-like cross-sectional morphology and well-defined rough surface microstructures, which are attributed to the synergistic roles of SiO--PEGDA as nanofillers and DA as interfacial cross-linker during secondary phase separation. Energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) analyses confirm that the combined action of nanoparticles and PDA significantly increases the density of hydrophilic functional groups on membrane surfaces and within pore channels. The membranes exhibit excellent hydrophilicity and underwater superoleophobicity, achieving an outstanding emulsion flux of 3537 Lm h bar and an oil removal efficiency of 98.5%. After 15 cycles of oil-water separation, the membranes maintain a high flux recovery rate of 85.6%. Moreover, the biomimetic membranes possess exceptional operational stability, as evidenced by consistent surface wettability under organic solvents, strong acid and high-salinity conditions.
聚合物膜的环保特性和能源效率使其成为水包油乳液分离的关键材料。然而，由油沉积导致的持续膜污染仍然是一个重大挑战，严重阻碍了它们在工业环境中的实际应用。在这项工作中，采用硫醇-烯光化学方法，以聚（乙二醇）二丙烯酸酯（PEGDA）和己二硫醇（HD）为单体合成了聚乙二醇化二氧化硅纳米颗粒（SiO₂-PEGDA）。通过气相诱导相分离（VIPS）将SiO₂-PEGDA纳米颗粒整合到一起，构建仿生聚偏氟乙烯（PVDF）膜，随后在多巴胺（DA）溶液中进行二次凝固。实验结果表明，仿生膜呈现出典型的海绵状横截面形态和清晰的粗糙表面微观结构，这归因于SiO₂-PEGDA作为纳米填料和DA作为界面交联剂在二次相分离过程中的协同作用。能量色散X射线光谱（EDS）和X射线光电子能谱（XPS）分析证实，纳米颗粒和聚多巴胺（PDA）的联合作用显著增加了膜表面和孔道内亲水官能团的密度。这些膜表现出优异的亲水性和水下超疏油性，实现了3537 Lm h bar的出色乳液通量和98.5%的除油效率。经过15次油水分离循环后，膜保持了85.6%的高通量回收率。此外，仿生膜具有出色的操作稳定性，在有机溶剂、强酸和高盐条件下表面润湿性保持一致，证明了这一点。
