Department of Chemical Engineering, Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue West , Waterloo , ON N2L 3G1 , Canada.
Key Lab of Organic Optoelectronics & Engineering Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China.
ACS Appl Mater Interfaces. 2019 Mar 6;11(9):9367-9373. doi: 10.1021/acsami.8b22159. Epub 2019 Feb 20.
Cellulose nanofibers (CNFs) aerogels with controllable surface wettability were prepared by grafting poly( N, N-dimethylamino-2-ethyl methacrylate) (PDMAEMA) polymer brushes via surface-initiated atom-transfer radical polymerization. After grafting PDMAEMA polymer, the surface of the aerogel was hydrophobic. However, in the presence of CO, the surface of the aerogel gradually changes from hydrophobic to hydrophilic. The porous structure and CO-responsiveness of PDMAEMA brushes within the CNFs aerogels allowed for the on-off switching of the oil-water mixture separation process. These CNFs aerogels were recyclable and displayed attractive separation efficiency for oil-water mixture and surfactant-stabilized emulsions. Furthermore, the switchable surface wettability holds an advantage of avoiding oil-fouling, which will greatly improve its recyclability.
通过表面引发原子转移自由基聚合在纤维素纳米纤维（CNFs）气凝胶上接枝聚（N，N-二甲基氨基-2-乙基甲基丙烯酸酯）（PDMAEMA）聚合物刷，制备了具有可控表面润湿性的纤维素纳米纤维气凝胶。接枝 PDMAEMA 聚合物后，气凝胶的表面是疏水性的。然而，在 CO 的存在下，气凝胶的表面逐渐从疏水性变为亲水性。CNFs 气凝胶内 PDMAEMA 刷的多孔结构和 CO 响应性允许油水混合物分离过程的开-关切换。这些 CNFs 气凝胶可回收利用，对油水混合物和表面活性剂稳定乳液显示出有吸引力的分离效率。此外，可切换的表面润湿性具有避免油污染的优势，这将大大提高其可回收性。
