高性能聚砜中空纤维膜的制备及性能研究

发布时间：2018-03-08 15:44

  本文选题：聚砜　切入点：中空纤维膜　出处：《天津工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：干-湿法纺丝制备聚砜中空纤维膜的过程中,由于铸膜液中的聚合物、溶剂和添加剂之间的相互作用,以及纺丝过程中铸膜液温度、凝固浴和芯液组成、凝固浴温度、卷绕速度等工艺参数的综合影响,导致对于制备不同类型(如高水通量、高截留率)的超微滤膜时,各因素对膜结构形态的形成和成形后膜性能的影响趋势和程度不同。此外,常规方法制备的高水通量的聚砜中空纤维微滤膜的微孔结构稳定性较差,随运行时间甚至存放时间的延长,水通量有不同程度的衰减。如何通过适当的后处理,提高膜结构的稳定性,减小膜在存放或运行过程中水通量的衰减,或通过纺丝-拉伸-热定型一步法制备较为稳定的高通量微滤膜,是工业生产应用中的重要研究课题。论文以铸膜液组成、中空纤维膜纺丝工艺参数及所制备的聚砜中空纤维膜为研究对象,采用膜水通量截留测试装置、扫描电镜、紫外分光光度计等仪器设备,对不同条件所制备的中空纤维膜和不同拉伸-热定型条件处理后的样品进行了测试分析。通过控制凝固浴温度、空气浴高度、芯液组成、添加剂种类和含量、聚合物浓度等参数,研究其对膜结构和性能的影响,并制备出高水通量超滤膜和高截留超滤膜。结果表明,凝固浴温度为70℃,空气浴高度为190mm,芯液中DMAc含量为70%时能制备出在0.1MPa测试压力下,通量高达1000L/(m2·h),对卵清蛋白的截留率为90%的高通量聚砜中空纤维超滤膜;聚合物浓度为33%,凝固浴温度为30℃,添加含量为12%时,制备出对PEG6000截留率达到99%,对PEG4000截留率达80%的高截留聚砜中空纤维超滤膜。实验中对已制备的高通量中空纤维微滤膜进行不同比例拉伸后,放入电热鼓风干燥箱中进行热处理。研究了拉伸率、热定型温度、热定型时间对膜水通量和结构的影响。结果表明:不同程度的拉伸-热定型对聚砜中空纤维微滤膜的水通量有明显影响。本实验中的最佳处理条件是拉伸10%后,60℃热定型1Omin,测试80min后膜丝的水通量较未处理的原丝提高22%。适当的拉仲-热定型对微滤膜的水通量和微孔结构稳定性有一定的提高。
[Abstract]:In the process of preparing polysulfone hollow fiber membrane by dry and wet spinning, due to the interaction among polymer, solvent and additive in casting solution, the temperature of casting film solution, the composition of solidification bath and core solution, the solidification bath temperature, The comprehensive influence of winding speed and other technological parameters on the preparation of different types of ultrafiltration membranes, such as high water flux and high retention rate, has different trends and degrees of influence on the formation of membrane structure and the properties of formed membranes. The micropore structure stability of high water flux polysulfone hollow fiber microfiltration membrane prepared by conventional method is poor. With the extension of running time and even storage time, the water flux decreases in varying degrees. To improve the stability of the membrane structure and reduce the water flux attenuation during the storage or operation of the membrane, or to prepare a more stable high-flux microfiltration membrane by spinning, stretching and heat setting. It is an important research subject in industrial production and application. The composition of casting membrane, the spinning process parameters of hollow fiber membrane and the prepared polysulfone hollow fiber membrane are studied in this paper. The membrane water flux retention test device is used, and the scanning electron microscope (SEM) is used. The hollow fiber membrane prepared under different conditions and the samples treated with different stretching and heat setting conditions were tested and analyzed by means of controlling coagulation bath temperature, air bath height, core liquid composition, and so on. The effects of additives, content and polymer concentration on the structure and properties of the membrane were studied, and the high water flux ultrafiltration membrane and high retention ultrafiltration membrane were prepared. The results showed that the coagulation bath temperature was 70 鈩，

本文编号：1584517