Emulsion-Templated, Magnetic, Hydrophilic–Oleophobic Composites for Controlled Water Removal

Emulsion-templated, hydrophilic–oleophobic porous materials are promising for the removal of a small amount of water from oil–water mixtures, but the maneuver and complete collection of these porous materials are challenging. Herein, we report the fabrication of magnetic, hydrophilic–oleophobic polyHIPE composites from reactive Fe3O4 nanoparticle-stabilized high internal phase emulsions through simultaneous bulk polymerization of water-soluble monomers and interface-catalyzed polycondensation of 1H,1H,2H,2H-perfluorooctyltriethoxysilane. The resulting composites were hydrophilic–oleophobic, with water droplets rapidly absorbed (within 20 s), and exhibited designable magnetic responsiveness. The hydrophilicity–oleophobicity enabled water to be removed through selective absorption from oil–water mixtures (including surfactant-stabilized water-in-oil emulsions), with a high separation rate over 99%. The magnetic-responsiveness enabled both the dry and the swollen composites to be maneuvered in a remote and contactless manner and to be fully collected. Therefore, the magnetic, hydrophilic–oleophobic polyHIPE composites are excellent candidates for the removal of water from water–oil mixtures with complete collection.