【作者】 齐丽环；

【导师】 安树林；

【作者基本信息】 天津工业大学 ， 材料学， 2008， 硕士

【摘要】 本文以聚砜中空纤维超滤膜为基膜，分别以间苯二胺和哌嗪为水相单体，均苯三甲酰氯为有机相单体，通过界面聚合反应在基膜表面形成超薄功能层，制备了芳香族聚酰胺／聚砜中空纤维复合膜。研究了中空纤维基膜的纺丝工艺，基膜预处理、单体结构对复合膜性能的影响，复合膜的分离性能等。以聚砜为基质材料，选择了多种成孔添加剂制成纺丝液，采用干-湿法纺丝工艺制成聚砜中空纤维基膜。研究了添加剂组成对基膜结构和性能的影响。其中，复合添加剂各组分的致孔机理有机配合，协同作用，使纺丝液处于亚稳定状态，有效控制纺丝液中凝固液的界面润湿性，控制相转化成膜机理，纺制出性能稳定、孔径适当、高透水通量的聚砜中空纤维基膜。在0．1MPa下，对4g／L卵清蛋白水溶液的截留率在85％左右，纯水通量高于250L．m^-2．h^-1。并对复合添加剂纺制基膜的工艺进行了详细的研究。本文选择两种水相单体与均苯三甲酰氯反应制备了聚酰胺／聚砜中空纤维复合膜。结果表明：采用哌嗪单体得到聚哌嗪均苯三甲酰胺／聚砜复合纳滤膜，对二价盐有较好的截留，0．7MPa下对2g／L MgSO₄水溶液的截留率为96．4％，水通量达94．4 L．m^-2．h^-1，但对一价盐截留率较低，0．7MPa下对0．5g/LNaCl的截留率低于30％；采用间苯二胺单体得到聚均苯三甲酰间苯二胺／聚砜复合膜，对一价和二价盐均有较高的截留，0．7MPa下对2g／L MgSO₄水溶液的截留率为98．8％，对0．5g/L NaCl的截留率为91．5％，但通量很低。详细研究了聚哌嗪均苯三甲酰胺／聚砜复合纳滤膜的分离性能，结果表明：该复合膜对二价或多价离子和相对分子质量大于300的物质均有较好的截留。将基膜经过乙醇预处理后制备聚哌嗪均苯三甲酰胺／聚砜复合纳滤膜，在0．7MPa下对2g／LMgSO₄水溶液的通量提高近一倍，截留性能变化不大。红外谱图分析结果表明，经过乙醇预处理，基膜表面有氢键产生，复合膜表面聚酰胺大分子的端基N-H或O-H伸缩振动吸收峰变强，说明乙醇预处理增强基膜表面极性，有利于提高界面聚合反应效率。依据膜分离机理中的溶解-扩散模型，存在于多孔支撑层和超薄功能层之间的氢键增强了复合膜与水分子之间的相互作用，有助于提高复合膜的产水率。更多还原

【Abstract】 In this paper, polyamide/ polysulfone（PSf） composite hollow fiber membrane was prepared by using PSf ultrafiltration hollow fiber membrane as support membrane, m-phenylene diamine（MPD） and piperazine（PIP） as the monomer in aqueous, trimesoylchloride（TMC） as the monomer in organic phase, fabricating an ultra thin polyamide functional layer on the substrate through interfacial polymerization. Spinning technics of hollow fiber, the effects of pre-treatment of substrate and the structure of monomers on the performance of composite membrane, and separate capability of composite membrane were studied.PSf hollow fiber membrane was prepared by dry-wet spinning technics, using kinds of additives, the effect of additives on the structure and performance of substrate membrane was researched. The components in composite additives make the induce-porous mechanism cooperate effectively, resulting in the spinning solution having proper dispersibility and stabilization, controlling the wetting capability of coagulating solution in spinning dope effectively, controlling the formation of membrane, preparing PSf hollow fiber membrane with steady performance, proper hole, and high flux. The membrane has a rejection of 85% for the solution of egg white albumin at the concentration of 4g/L, and water flux more than 250 L .m^-2.h^-1 under an operating pressure of 0.1MPa. Spinning technics of substrate membrane with composite additives was investigated in detail.Two monomers in aqueous were selected, reacting with TMC, PA/PSf composite membranes were prepared. The results showed as follows, when using PIP as monomer, the composite membrane prepared has a good rejection for salt with two charges, but a worse rejection for salt with one charge. It has a salt rejection of 96.4% for MgSO₄ at the concentration of 2g/L, and a high water flux of 94.4 L .m^-2.h^-1 under an operating pressure of 0.7MPa. But a low salt rejection for NaCl, lower than 30%. When using MPD as monomer, the composite membrane prepared has a good rejection both for salt with one charge and two charges, but a low permeating flux. Separate capability of Polypiperazine trimesoyl amid/PSf nanofiltration composite membrane was studied, it has a good rejection for multi-valent ions and substance with molecular weight higher than 300.Polypiperazine trimesoyl amid/PSf nanofiltration composite hollow fiber membrane was prepared using substrate pre-treated with ethanol. The permeating flux of composite membrane increased about one times for MgSO₄ at the concentration of 2g/L, under an operating pressure of 0.7MPa, while salt rejection changed little. Hydrogen bond was formed between porous substrate and ultra thin polyamide functional layer, it strengthened the action between composite membrane and water compound, according to the model of dissolve and diffuse from the mechanism of membrane separating.更多还原