Posted by In this research, superhydrophilic and underwater superoleophobic coatings on poly(vinylidene fluoride) (PVDF) membrane are constructed via interfacial polymerization following “thiol-ene” click reaction. These two industrialization methods are combined through a distinctive “bridge”, quaternized imidazole-β-cyclodextrin (CD-Vi). It not only has seven viny groups at the narrow end and 14 hydroxyl groups at the wide end, but also possesses a quantity of charge. The superwetting, anti-oil fouling, and self-cleaning properties of the composite membrane are significantly promoted even against viscous crude oil. The composite membrane can efficiently separate various surfactant free and surfactant stabilized oil-in-water emulsions with a batch of high fluxes, and the corresponding separation efficiency reaches nearly 100 %. Moreover, the durable and robust composite coatings not only can withstand mechanical wear (rubbing 50 times) and chemical corrosion (1 M of NaCl, NaClO, HCl, NaOH) without changing its underwater superoleophobicity, but also achieve up to 30 cycles of recyclability during the continuous separation of oily emulsions.
The paper is illustrated with spectacular videos.
Liyuan Fan, Bin Peng, Xinzhao Luo, Shaobin Wen, Tianheng Wang, Qiang Zhang (2025) Cross-linked porous cyclodextrin polymer as superhydrophilic and underwater superoleophobic coating of membrane for efficient oil/water emulsion separation. Separation and Purification Technology 354(8), 129207. https://doi.org/10.1016/j.seppur.2024.129207.