溶液相转化法制备PSF超滤膜过程中的结构控制及其性能研究

发布时间：2018-05-06 23:06

本文选题：聚砜超滤膜 + 溶液相转化法　；参考：《浙江大学》2011年硕士论文

【摘要】：本文针对聚合物超滤膜在较高压力下应用时很容易被压密的现象,通过调控铸膜液性质,制备系列密度梯度分布海绵状结构、耐压性好和通量高的聚砜(PSF)超滤膜。首先,设计粘度可调控的PSF/DMAC和PSF/DMAC/PVP共8个不同体系。通过研究铸膜液的粘度和浊点,相分离过程的光透实验,膜的表面和断面形貌,膜孔径、孔隙率及水通量等,发现对于由溶液相转化法制备得到的聚砜超滤膜而言,铸膜液的零切粘度是影响膜形貌、结构与通量的重要因素之一。其次,设计PSF/DMAC/PVP, PSF/DMAC/Ethanol和PSF/DMAC/Ethanol/PVP共12个不同添加剂含量的体系。通过研究膜的水通量,表面和断面形貌,耐压稳定性,膜耐压前后孔隙率的变化等,发挥PVP和乙醇对铸膜液的共同调控作用,得到了密度梯度分布海绵状结构、耐压性好和通量高的PSF超滤膜。最后,通过分散聚合法合成了系列不同单体组成比例的SiO2-PAMPS纳米粒子,并以SiO2-PAMPS为添加剂,制备PSF杂化超滤膜。通过考察杂化膜的水通量,孔径和孔隙率,表面和断面形貌,力学性能,耐压稳定性及杂化膜振荡前后的接触角等,发现SiO2-PAMPS纳米粒子在杂化膜表面非常稳定,杂化膜的水通量,力学性能,耐压性能明显提高。由PSF/DMAC/Ehanol/SiO2-PAMPS4(单体的摩尔比(MSiO2/MPAMPS)为15.3：1,浓度为0.3 wt%)体系所得的杂化膜,纯水通量在0.1 MPa为190 L/m2.h,拉伸强度和断裂伸长率分别为4.3 MPa和20.5%,断面结构在0.5 MPa下连续操作4h,没有压密现象发生。
[Abstract]:In view of the phenomenon that polymer ultrafiltration membrane is easily compacted when it is applied at high pressure, a series of polysulfone (PSF) ultrafiltration membranes with density gradient distribution spongy structure, good pressure resistance and high flux are prepared by regulating the properties of casting solution. First, eight different systems of PSF/DMAC and PSF/DMAC/PVP with adjustable viscosity were designed. By studying the viscosity and cloud point of the casting solution, the photo-transmittance experiment of phase separation process, the surface and cross-section morphology of the membrane, the pore size, porosity and water flux of the membrane, it is found that for the polysulfone ultrafiltration membrane prepared by the solution phase inversion method, The zero shear viscosity of casting solution is one of the important factors affecting the morphology, structure and flux of the membrane. Secondly, 12 systems of PSF / DMAC / PVP, PSF/DMAC/Ethanol and PSF/DMAC/Ethanol/PVP were designed. By studying the water flux, the surface and section morphology, the stability of the membrane and the change of the porosity before and after the membrane compression, the spongy structure of density gradient distribution was obtained by using PVP and ethanol to regulate the casting solution. PSF ultrafiltration membrane with good pressure resistance and high flux. Finally, a series of SiO2-PAMPS nanoparticles with different monomer ratios were synthesized by dispersion polymerization, and PSF hybrid ultrafiltration membrane was prepared with SiO2-PAMPS as additive. By investigating the water flux, pore size and porosity, surface and section morphology, mechanical properties, pressure stability and contact angle of hybrid membrane before and after oscillation, it was found that SiO2-PAMPS nanoparticles were very stable on the surface of hybrid membrane, and the water flux of hybrid membrane was very stable. The mechanical properties and the voltage resistance are obviously improved. The pure water flux of the hybrid membrane obtained from PSF / DMAC / Ehanol / SiO2-PAMPS4 system was 15.3: 1, and the pure water flux was 190Lm2.h. the tensile strength and elongation at break were 4.3 MPa and 20.5wt h, respectively. The cross section structure was operated continuously at 0.5 MPa for 4hs without compaction.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TQ028.8

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