文献类型：期刊文献

英文题名：Superhydrophobic modification of PVDF-SiO2 electrospun nanofiber membranes for vacuum membrane distillation

作者：Dong, Zhe-Qin[1];Ma, Xiao-Hua[1];Xu, Zhen-Liang[1];Gu, Zhi-Yun[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai Key Lab Mutiphase Mat Chem Engn, Membrane Sci & Engn R&D Lab,Chem Engn Res Ctr, Shanghai 200237, Peoples R China

年份：2015

卷号：5

期号：83

起止页码：67962

外文期刊名：RSC ADVANCES

收录：;EI(收录号：20153301179369);WOS:【SCI-EXPANDED(收录号:WOS:000359537000069)】；

基金：The authors thank for financial support by 2013 Year Special Project of the Development and Industrialization of New Materials of National Development and Reform Commission in China (20132548), the National Science and Technology Support Project of China (2014BAB07B01), the National Natural Science Foundation of China (21176067 and 21406060), the Shanghai Yang-fan Plan for Young Talents (14YF1404800), the General Financial Grant from the China Postdoctoral Science Foundation (2013M540336 and 2015M571513), and the Open Project of State Key Laboratory of Chemical Engineering (SKL-ChE-14C03) for giving financial support.

语种：英文

外文关键词：Hydrophobicity - Nanofibers - Contact angle - Distillation - Pore size - Composite membranes - Fluorine compounds - Wetting

摘要：Electrospun nanofiber membranes having a hierarchical structure with multilevel roughness were generated via electrospinning of poly(vinylidene fluoride) (PVDF)-SiO2 blend solutions. The composite PVDF-SiO2 nanofiber membranes were then endowed with superhydrophobicity by the fluorosilanization of the surface with low surface energy fluoroalkylsilane (FAS). The results showed that when the SiO2 content in the dope solutions increased from 0 wt% to 8 wt%, the water contact angles of the FAS modified nanofiber membranes increased significantly from 130.4 degrees to 160.5 degrees. The increment of the silica content in the dope solutions decreased the fiber diameters and pore sizes of the modified membranes, while the mechanical properties were enhanced with the silica addition. The liquid entry pressures of the membranes increased gradually from 84 kPa to 195 kPa with silica addition due to the increased contact angles and decreased pore size. Vacuum membrane distillation experiments were carried out for the modified nanofiber membranes to evaluate the anti-wetting properties. The optimal superhydrophobic nanofiber membrane maintained a stable flux of 31.5 kg m(-2) h(-1) with a permeate conductivity approximately 10 mu s cm(-1) over the entire test, while the fluxes and conductivities of the nanofiber membranes without superhydrophobicity showed a significant decrease and increase, respectively. The results indicated that the superhydrophobic modification process rendered the nanofiber membrane anti-wetting properties without compromising its excellent permeability.