纳米SiO_2共混对PVDF超滤膜的结构及抗污染性能的影响

EFFECT OF NANO-SiO_2 BLENDING ON THE STRUCTURE AND ANTI-FOULING PROPERTY OF PVDF ULTRAFILTRATION MEMBRANES

为了揭示纳米SiO_2共混对PVDF超滤膜性能及结构的影响。利用非溶剂相转化法(NIPS)成膜机理,制得了不同纳米SiO_2含量的PVDF/SiO_2共混改性超滤膜。综合研究纯水通量、接触角、强度及截留率等性能,以牛血清蛋白水溶液为标准污染物,通过评价PVDF/SiO_2共混改性超滤膜的抗污染能力,使用扫描电子显微镜及原子力显微仪分别对膜结构及微界面形貌进行观测。结果表明,纳米SiO_2共混改性可提高膜的亲水性,促进指状孔、致密皮层及致密海绵层结构的形成;从而提高膜的通量、强度及抗污染性能,纳米SiO_2最优添加量为5%。

In order to reveal the effects of blending modification of Nano-SiO_2 on the properties and structure of PVDF ultrafiltration membrane,the method of non-liquid phase separation（ NIPS） for membrane forming was used in this paper to make different PVDF/Nano-SiO_2 ultrafiltration membranes modified with different nano-SiO_2 contents. Combining the analysis of properties including pure water flux,contact angle,strength and rejection rate,the author observed the structure of membranes and profile of micro-interfaces by scanning electron microscope and atomic force microscope,evaluated antipollution capacity of PVDF/Nano-SiO_2 modified ultrafiltration membranes,with the bovine serum albumin solution as the＂criteria＂pollutant. The results showed that the blending modification of nano-SiO_2 could raise the hydrophilia of membranes and the formation of finger-like pore,compact cortex and spongy structures,therefore improved the flux,strength and antipollution capacity. And the property was optimal when dosage of Nano-SiO_2 was 5%.