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疏水性聚偏氟乙烯(PVDF)膜的亲水化改性是当前膜分离技术研究的热点之一。利用共混改性将纳米TiO2颗粒加入铸膜液,通过溶胶凝胶法制备改性PVDF中空纤维膜。采用AFM和SEM对膜表面进行表征,以接触角,孔隙率,水通量和平均孔径为评价标准,确定改性膜中纳米TiO2颗粒投加的最佳比例。结果表明:与未改性膜相比,改性膜表面平滑,粗糙度明显降低;改性膜断面的孔状结构更加微小,内部主要以海绵状为主;改性膜的接触角及孔隙率均有所改变,膜表面的亲水性增强,纯水通量提高4-5倍,最大达657.3L/m2.h。
Hydrophilic modification of hydrophobic polyvinylidene fluoride (PVDF) membranes is one of the hot topics in current membrane separation technology. Nano-TiO2 particles were added into casting solution by blending modification, and modified PVDF hollow fiber membrane was prepared by sol-gel method. The surface of the membrane was characterized by AFM and SEM. The contact angle, porosity, water flux and average pore size were used as the evaluation criteria to determine the best proportion of nano-TiO2 particles in the modified membrane. The results show that the surface of the modified film is smooth and the roughness is obviously lower than that of the unmodified film. The pore structure of the modified film is more subtle and the internal is mainly spongy. The contact angle and porosity All changed, the hydrophilicity of the membrane surface enhanced, pure water flux increased 4-5 times, up to 657.3L / m2.h.