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以羟基多壁碳纳米管(MWCNTs-OH)作为添加剂,采用非溶剂致相转化法制备MWCNTs-OH修饰聚偏氟乙烯中空纤维超滤膜.先将MWCNTs-OH加入溶剂N,N-二甲基乙酰胺(DMAC)中超声处理以加强其分散性,力求制得均一铸膜液.通过水通量、截留率、红外光谱,XRD及力学性能测试表征膜性能,并用SEM观察其形貌.重点考察MWCNTs-OH对中空纤维膜通量、截留和力学性能的影响.结果表明,当MWCNTs-OH质量分数从0增加到0.09 wt%时,修饰膜的水通量由376.40 L/m2h增加到510.90 L/m2h,而对BSA截留率保持稳定(95%以上);膜的拉伸强度由1.68 MPa提高到2.42 MPa,断裂伸长率由44.18%提高到76.93%.SEM和TEM研究表明,MWCNTs-OH添加量较少时,在膜中可均匀分散,添加量大时则容易团聚.XRD和IR图谱分析表明MWCNTs-OH参与聚合物结晶过程而未改变聚合物晶型.
MWCNTs-OH modified poly (vinylidene fluoride) hollow fiber ultrafiltration membrane was prepared by non-solvent phase inversion method using MWCNTs-OH as additive.The MWCNTs-OH was first added to the solvent N, N-dimethyl (DMAC) to enhance its dispersibility, and strive to make a uniform casting solution.The membrane performance was characterized by water flux, rejection, infrared spectroscopy, XRD and mechanical properties tests, and the morphology was observed by SEM. The effects of MWCNTs-OH on the flux, entrapment and mechanical properties of hollow fiber membranes were investigated. The results showed that the water flux of the modified membranes increased from 376.40 L / m2h to 0.09 wt% when the mass fraction of MWCNTs-OH was increased from 510.90 L / m2h, while the retention of BSA remained stable (above 95%). The tensile strength of the membrane increased from 1.68 MPa to 2.42 MPa and the elongation at break increased from 44.18% to 76.93% .SEM and TEM studies showed that MWCNTs -OH could disperse uniformly in the film when the amount of -OH added was small, and easily aggregated when the amount of -OH added was large.XRD and IR spectra showed that MWCNTs-OH was involved in the crystallization of polymer without changing the crystal form of polymer.