Key Lab of Science and Technology of Eco-Textile, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology, Innovation Center for Textile Science and Technology of DHU, Donghua University, Shanghai, 201620, PR China.
Key Lab of Organic Optoelectronics & Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, PR China.
Carbohydr Polym. 2020 Jun 1;237:116133. doi: 10.1016/j.carbpol.2020.116133. Epub 2020 Mar 6.
To obtain efficient oil-water separation materials with responsiveness, cellulosic porous materials with switchable wettability in response to pH changes were developed by reacting cellulose acetoacetate sponges with alkylamines of varying carbon chain length via dynamic covalent enamine bonds. The resulting sponges reversibly changed between being superhydrophilic (θ = 0°) and highly hydrophobic (maximal θ = 146°) under suitable pH conditions while maintained the favorable porous structures. Notably, the functionalized sponges exhibited high and selective oil absorption capacity (40-80 g/g) and satisfying desorption ability of 80%, and could efficiently separate oil-water mixtures and emulsions with extremely high efficiency (> 99%) in a controllable manner. With the three-dimensional micro/nano porous structure, switchable wettability and intrinsic environmentally friendliness, the pH responsive cellulosic sponges developed here hold great potential in controllable oil-water separation and oily wastewater purification.
为了获得具有响应性的高效油水分离材料，通过纤维素乙酰乙酸酯海绵与不同碳链长度的烷基胺之间的动态共价烯胺键反应，开发了对 pH 值变化具有可切换润湿性的纤维素多孔材料。在合适的 pH 条件下，所得的海绵在超亲水（θ=0°）和高疏水性（最大θ=146°）之间可实现可逆转变，同时保持了有利的多孔结构。值得注意的是，功能化海绵表现出高且选择性的吸油能力（40-80 g/g）和令人满意的 80%解吸能力，并且能够以可控的方式有效地分离油水混合物和乳液，效率极高（>99%）。具有三维微/纳多孔结构、可切换润湿性和内在环境友好性，这里开发的 pH 响应性纤维素海绵在可控的油水分离和含油废水净化方面具有巨大的潜力。
