【作者】 梅勇；

【导师】 王庆瑞；

【作者基本信息】 东华大学 ， 材料学， 2004， 硕士

【摘要】 聚醚砜(PES)是一种综合性能优良的聚合物膜材料，其玻璃化温度高达225℃，具有较高的拉伸强度和优良的化学稳定性、耐热性、耐压力，耐腐蚀等性能。常作为超滤、纳滤膜的材料。聚醚砜膜的一个重要的应用方向是血液过滤。由于用于人体血液过滤的聚醚砜膜要求对有毒物质如肌肝和尿素去除率要高，同时水透过量不要太大(以免造成病人脱水现象)又不要太低(以免影响救治效率)。单凝固浴法制成的膜要么去除率很高，但同时水通量也很高，要么去除率不高，水通量也不大。J.A.van’t Hof等提出的双凝固浴(dual-bath coagulation method)成膜方法制膜从理论上可以达到肌肝、尿素选择分离率高而水通量适中的要求，从而可能应用于血液过滤领域中。 为了改善和优化聚醚砜超滤膜(单浴法)在血液过滤实际应用中的性能，本论文以J.A.van’t Hof等提出的双凝固浴法为基础，以聚醚砜(PES)为主要成膜材料，以二甲基亚砜为溶剂，并添加一定分子量的致孔剂(PVP，聚乙烯吡咯烷酮)以及一定分子量的添加剂(PEG，聚乙二醇)按照一定配比在一定温度下制成透明均一的铸膜液，静置脱泡后在一定的工艺条件下制成聚醚砜平板膜和中空纤维膜，然后通过测试膜的结构和性能来评估其用于血液过滤中的前景。 本论文包括以下五个方面内容： 1．研究了铸膜液中聚醚砜的质量分数和温度对膜结构与性能的影响。随着铸膜液浓度的上升，水通量呈现总体下降的趋势；膜对低分子物质的去除率先上升，然后下降，随后又略有上升。随着铸膜液温度的上升，水通量先是明显下降，然后略有上升。膜对低分子物质的去除率先是增加，然后急剧下降。东华大学硕士论文 2.研究了铸膜液的预蒸发时间对二次成形聚醚矾膜结构与性能的影响。随着预蒸发时间的延长，水通量先减小后增大，在235时有一最小值;肌肝和尿素去除率均是先升高而后降低然后再稍为升高的趋势。随着预蒸发时间的延长，膜表面的孔变小变少，膜的致密层越来越明显，支撑层有大而深的孔结构出现。随着预蒸发时间的延长，膜的孔隙率上升，平均孔径下降。 3.研究了第一凝固浴的组分和第一凝固浴中的停留时间对膜表层结构与膜性能的影响。双凝固浴成膜方法可同时获得较厚的致密表面层和疏松多孔的支撑层。以异丙醇作为凝固剂时，它与溶剂的互溶性要优于正丁醇和正戊醇。随着在第一凝固浴中停留的时间越长，膜的水通量越低，肌肝和尿素的去除率均是先升高后下降然后稍有上升的趋势。 4.研究了第二凝固浴温度和浓度对聚醚矾膜的结构与性能的影响。随着第二凝固浴温度的上升，水通量一直上升，肌肝和尿素的去除率先是上升，然后下降，最后又有略微上升的趋势。随着第二凝固浴DMSO浓度(wt/wt)的增加，水通量和肌肝、尿素去除率均是先下降，然后保持在较低的水平，最后又呈上升的趋势。 5.研究了二次成形聚醚矾中空纤维膜的纺制条件对其性能与结构的影响。纺制条件包括:纺丝方法、填充液的压力和种类、聚醚矾质量分数、聚乙烯毗咯烷酮的相对分子质量、聚乙二醇的相对分子质量以及在第一凝固浴中的凝固长度等。纺丝方法宜采用干湿法。随着填充液压力的提高，纤维的内、外径增加，壁厚减小，水通量增大。异丙醇作为填充液时，膜的结构比较致密;水作为填充液时，膜的结构是典型的均匀的指状孔结构;2。%的甘油水溶液作为填充液时，膜的结构基本上是指状孔结构，但分布不均匀。随着聚醚矾在铸膜液中的浓度的增大，中空纤维膜的水通量呈下降的趋势。随着PVP相对分子质量的增大，水通量呈上升的趋势。随着PEG相对分子质量的增加，聚醚飒中空纤维膜的水通量呈上升的趋势。随着在第一种凝固浴中凝固长度的增加，聚醚枫中空纤维膜的水通量呈下降的趋势。更多还原

【Abstract】 PES is a good membrane materials which possess excellent properties, such as high mechanical strength, good chemical stability and resistance to heat, pressure and erosion, Its temperature of glass transition is 225. PES is used to make ulfrafiltration membrane and nanofiltration membrane. Hemofiltration (HF) is an important applied field, membranes can be used for HF, which requires that the clearance rate of toxins such as urea and creatintine should be high and water flux should be moderate. Membranes made by single-bath coagulation method either have high clearance rate and high water flux or have low clearance rate and low water flux.The dual-bath coagulation method suggested by J.A.van’t Hof could be used in membranes with high selectivity clearance rate of low-molecular weight substances and moderate water flux theoretically. Therefore it may be applied in the field of hemofiltration.To improve and optimize the performance of the PES ultrafiltration membrane applied in the HF, here the flat membranes and hollow fiber (HF) membranes are made in certain conditions based on the dual-bath coagulation method where PES is used as the membrane material, DMSO as solvent and PVP &PEG as additives This paper includes five parts as follow:1. The effects of PES concentration and temperature in casting solution on the structure and properties on PES ultrafiltration membranes are studied. As the concentration of PES solution increases, the pure water flux decreases and the clearance rates of low-molecular weight substances such as urea and creatintine first increase, then decrease, and increase slightly at last. As the temperature increases, the water flux first decreases evidently, then increases slightly and the clearance rates of low-molecular weight substances first increase, then decrease shaply.2. The effects of pre-evaporation time on the structure and properties of PESmembranes by two-step formation. As the pre-evaporation time increases, the water flux first decreases then increase, at the 23rd second it reaches the minimum value; the clearance rates of urea and creatintine increase first then decrease and increase a little at last. As the pre-evaporation time increases, the holes on the membrane surface becomes smaller and less, dense layer is becoming more evident with large and deep holes in supporting layer; and porosity increases as well- as average hole diameter decreases.3. The effects of the component and the time in the first coagulation bath on the structure and’ properties of PES membranes are studied. The dense top layer as well as porous supporting layer can be made by duel-bath coagulation method simultaneously. When 2-propanol (IPA)is used as a coagulation reagent, it has better dissolving ability with solvent than 1-butanol and 1-pentanol. As the time in the first coagulation bath increases, the water flux decreases and the clearance rates of urea and creatintine both first increase, then decrease and increase a little at last.4. The effect of the temperature and concentration of the second coagulation bath on the structure and properties of PES membranes are studied. As the temperature of the second coagulation bath increases, the water flux increases and the clearance rates of urea and creatintine first increase then decrease and increase a little at last. As the DMSO concentration (wt/wt) in the second coagulation bam increases, the water flux and the clearance rates of urea and creatintine first decrease men keep in a relatively low level and increase at last.5. The effects of spinning conditions on the structure and properties of PES HF membranes by two-steps formation are studied. The spinning conditions include spinning methods, the pressure and types of filling liquid, the PES concentration, the molecular weight of PVP and PEG and the coagulation length in the first coagulation bam. The spinning method should be Dry-spray wet-spinning method is adopted. As the pressure of filling liquid increases, the inrier and outer更多还原