Huang Jianjia, Zhang Zhenqiang, Weng Jiahao, Yu Danfeng, Liang Yueyan, Xu Xiubin, Qiao Zhiwei, Zhang Ganwei, Yang Hui, Wu Xu
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.
School of Chemistry and Chemical Engineering, Guangdong Provincial Key Lab for Green Chemical Product Technology, South China University of Technology, Guangzhou 510640, China.
ACS Appl Mater Interfaces. 2020 Dec 16;12(50):56530-56540. doi: 10.1021/acsami.0c18825. Epub 2020 Dec 7.
Materials with opposite affinities toward oil and water have been extensively used to coat porous substrates for oil-water separation, but the applications of these materials have been limited by the need for complex coating processes as well as the short-term adherence of these materials onto different substrates under extreme conditions. As reported herein, the robust porous polyurethane hydrogel has been theoretically and structurally designed with ultralow-oil-adhesion properties which is free stand without depending on additional substrates. The combination of superhydrophilic properties along with the underwater superoleophobic behavior of this porous hydrogel allows gravity driven separations of oil-water mixtures, and its antiadhesion performance toward oil prevents undesirable oily fouling. The underwater superoleophobic properties were also illustrated by molecular dynamics simulation to understand the resisting effect of hydrated layers. The as-prepared porous hydrogel shows ultrahigh oil-water separation efficiencies of 99.9% for various oil-water mixtures, ranging from those containing viscous oils (pump oil and peanut oil) to organic solvents (-hexane, -hexadecane, and toluene). In addition, this hydrogel is durable even with exposure to various harsh conditions including acidic and basic media (pH 0-14) as well as exposure to mechanical abrasion. We believe that the combination of facile preparation, substrate independence, gravity driven separation, antifouling properties, high durability, as well as the outstanding separation flux and efficiency of this robust porous hydrogel will help to advance the design and application of materials in oil-water separation fields.
对油和水具有相反亲和力的材料已被广泛用于涂覆多孔基材以进行油水分离，但这些材料的应用受到复杂涂覆工艺的需求以及这些材料在极端条件下在不同基材上的短期附着力的限制。如本文所报道，坚固的多孔聚氨酯水凝胶已在理论和结构上进行了设计，具有超低的油附着力特性，无需依赖额外的基材即可独立存在。这种多孔水凝胶的超亲水性与水下超疏油性相结合，使得油水混合物能够在重力作用下实现分离，并且其对油的抗粘附性能可防止不期望的油污结垢。还通过分子动力学模拟说明了水下超疏油性，以了解水合层的抵抗作用。所制备的多孔水凝胶对各种油水混合物（从含粘性油的混合物（泵油和花生油）到有机溶剂（正己烷、正十六烷和甲苯））显示出99.9%的超高油水分离效率。此外，即使暴露于各种恶劣条件下，包括酸性和碱性介质（pH值0 - 14）以及机械磨损，这种水凝胶仍具有耐久性。我们相信，这种坚固的多孔水凝胶的简便制备、不依赖基材、重力驱动分离、防污性能、高耐久性以及出色的分离通量和效率的结合，将有助于推动油水分离领域材料的设计和应用。
