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针对聚醚砜亲水性差的问题,以氯磺酸为磺化剂对聚醚砜进行磺化,制得不同磺化度的磺化聚醚砜及磺化聚醚砜分离膜.采用傅立叶变换红外光谱(FTIR)、差示扫描量热(DSC)和热重分析(TGA)对磺化聚醚砜进行了表征,并对分离膜水通量进行了测定.结果表明:随着磺化度的提高,磺化聚醚砜的玻璃化转变温度提高;在质子性极性溶剂中的溶解性增加,在非质子极性溶剂中的溶解性降低;亲水性提高,分离膜的水通量随之增加. 相似文献
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针对商业聚醚砜(PES)膜表面亲水性差,在络合超滤除锑过程中膜通量损失较大的问题。采用一步共涂覆改性法,通过在PES基膜表面形成聚多巴胺和二氧化硅纳米颗粒杂化涂层,得到高亲水性表面。对改性膜进行了表征和络合超滤实验。结果表明,优化改性条件为TEOS投加量0.6 g、时间9 h,此时制备的膜接触角仅为17.5°,亲水性能显著提高;超滤过程中膜通量有效提升,而且锑截留率可从改性前的75.2%提高至77.4%。改性膜在循环超滤实验中只经过清水冲洗即可恢复90%以上的初始膜通量,具有较好的运行稳定性。 相似文献
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探索纳米羟基磷灰石(n—HA)与聚醚砜(PES)电纺的最佳比例,制备新型纳米材料,并探讨其骨细胞相容性。分别以n-HA/PES:20/80,15/85,10/90(质量分数,下同),PES22%为电纺的比例,用N,N.二甲基甲酰胺(DMF)作溶剂,通过气电幼的方法制备了纳米羟基磷灰石与聚醚砜的复合纳米材料,运用扫描电镜、X射线能谱分析等方法进行检测,并在制得的纳米材料上接种成骨细胞,发现当n—HA与PES比例为10/90时,纺丝效果较好,纤维分布均匀;接种成骨细胞后,与阴性对照组比较,细胞在增殖上具有优势。从而证明气电纺制备的n—HA/PES纳米材料具有良好的骨细胞相容性。 相似文献
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溶剂/非溶剂体系对聚醚砜微孔膜性能和结构的影响 总被引:1,自引:0,他引:1
以N,N-二甲基乙酰胺(DMAc)、N-甲基吡咯烷酮(NMP)和N,N-二甲基甲酰胺(DMF)为溶剂,乙醇(EtOH)、异丙醇(IPA)、正丁醇(BuOH)、一缩二乙二醇(DegOH)、聚乙二醇400(PEG400)为非溶剂添加剂,研究了溶剂/非溶剂体系对聚醚砜(PES)膜的结构和性能的影响.改变铸膜液体系中的非溶剂含量对膜的结构和性能有很大影响,但是这种影响不是以非溶剂的绝对含量来衡量的,而取决于非溶剂/溶剂的比值.改变溶剂的组成和配比也改变了溶剂/非溶剂体系,体系的溶度参数越接近PES的溶度参数,与PES的相容性越好,但是膜的通量较小.实验结果表明,采用NMP(或DMAc)与DMF以适当比例混合作溶剂,比采用单一NMP(或DMAc)作为溶剂制得的膜通量要大.通过改变溶剂配比,可实现对膜的表面开孔率、孔径、断面结构等参数的微控. 相似文献
7.
ZHU Sijun HE Chunju MEI Yong WANG Qingrui 《武汉理工大学学报(材料科学英文版)》2005,20(B12):123-125
The dual-bath coagulation method was used for the preparation of PES membrane in this experiment. The main intent of this stndy was to assess the efforts of gelation conditions on the structures and properties. The dense top layer as well as porous supporting layer can be made by duel-bath coagulation method simultaneous- ly. Different internal quench medium obtained different membrane with different structures. With the increase in time in the first coagulation bath, pure water flux decreased and the clearance rates of urea and creatinine both first increased then decreased and increased slightly in the end. With the temperature of the second coagtdation bath increasing, pure water flux increases and the clearance rates of urea and creatinine first increases then de- creases and increases a little at last. Higher DMSO concentration (wt/wt) in the second coagulation bath results in the increase of pure water flux and the decrease of urea & creatinine clearance rates. 相似文献
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Polyethersulfone was sulfonated by changing the reaction time with sulfuric acid. The degree of sulfonation and ion exchange capacity were determined. Sulfonation of polyethersulfone was confirmed by FT-IR analysis and a new peak at 1025 cm?1. Inorganic materials such as carbon nanotubes, graphene, and kaolinite nanoparticles were synthesized. The effects of three nanoparticles on thermal stability and water uptake of sulfonated polyethersulfone were investigated. The morphology of membranes were also altered due to the addition of inorganic materials. The proton conductivity of the modified membranes increased with respect to increase in relative humidity. 相似文献
10.
Improving Blood Compatibility of Polyethersulfone Hollow Fiber Membranes via Blending with Sulfonated Polyether Ether Ketone 下载免费PDF全文
Appropriate membrane for blood contacting applications requires hemocompatibility and high permeation flux; it should inhibit proteins or platelets adsorption and still possess high permeability. Aiming to improve the polyethersulfone (PES) hollow fiber membrane hemocompatibility, sulfonated polyether ether ketone (SPEEK) is self‐synthesized in the present research and added to PES in different ratios. Scanning electron microscopy images have revealed significant changes in PES membranes structure after addition of SPEEK, which can influence water permeation property of the membranes. Water contact angles of the membranes have reduced from 75° to 50° after addition of 4 wt% SPEEK. Influence of SPEEK addition on hemocompatibility of the PES membranes is evaluated via protein (bovine serum albumin) adsorption, platelet attachment, and coagulation time (APTT and TT) assays. Obtained results reveal that hemocompatibility of the modified hollow fiber membranes is enhanced as a result of emerging repulsive forces between negative charges on the membranes surface and negatively charge blood components.