Li Jiao, Ding Hao, Zhang Heqiang, Guo Chunlin, Hong Xiaoyan, Sun Luyi, Ding Fuchuan
College of Chemistry and Materials Science & Fujian Key Laboratory of Polymer Science, Fujian Normal University, Fuzhou 350007, China.
Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
Materials (Basel). 2020 Feb 13;13(4):842. doi: 10.3390/ma13040842.
Superhydrophobic methylated silica with a core-shell structure was successfully fabricated by a sol-gel process. First, a pristine silica gel with an average particle size of ca. 110 nm was prepared, using tetraethylorthosilicate (TEOS) as a precursor, ethanol as a solvent, and NHOH as a catalyst. Then, the superhydrophobic methylated silica sol was prepared by introducing methyltrimethoxysilane (MTMS), to graft the surface of the pristine silica gel with methyl groups. The structure and morphology of the methylated silica sol were characterized by Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM), and transmission electron microscope (TEM). The characterization results showed that methyl groups were successfully grafted onto the surface of the pristine silica, and the diameter of the methylated silica was increased by 5-10 nm. Various superhydrophobic surfaces on glass, polyethylene terephthalate (PET) fabric, cotton, open-cell polyurethane (PU) foam, and polypropylene (PP) filter cloth were successfully constructed by coating the above substrates with the methylated silica sol and reached with a maximum static water contact angle and slide angle of 161° and 3°, respectively. In particular, the superhydrophobic PP filter cloth exhibited promising application in oil-water separation. The separation efficiency of different oil-water mixtures was higher than 96% and could be repeated at least 15 times.
通过溶胶-凝胶法成功制备了具有核壳结构的超疏水甲基化二氧化硅。首先，以正硅酸乙酯（TEOS）为前驱体、乙醇为溶剂、NHOH为催化剂，制备了平均粒径约为110 nm的原始硅胶。然后，通过引入甲基三甲氧基硅烷（MTMS）制备超疏水甲基化硅溶胶，使原始硅胶表面接枝甲基。采用傅里叶变换红外光谱（FTIR）、场发射扫描电子显微镜（FE-SEM）和透射电子显微镜（TEM）对甲基化硅溶胶的结构和形貌进行了表征。表征结果表明，甲基成功接枝到原始二氧化硅表面，甲基化二氧化硅的直径增加了5-10 nm。通过用甲基化硅溶胶涂覆上述基材，成功在玻璃、聚对苯二甲酸乙二酯（PET）织物、棉、开孔聚氨酯（PU）泡沫和聚丙烯（PP）滤布上构建了各种超疏水表面，最大静态水接触角和滑动角分别达到161°和3°。特别是，超疏水PP滤布在油水分离方面展现出了良好的应用前景。不同油水混合物的分离效率高于96%，且至少可重复使用15次。
