【作者】 谢宇梅；

【导师】 濮德林；

【作者基本信息】 四川大学 ， 生物医学工程， 2001， 硕士

【摘要】 本文以4，4’-二苯基甲烷二异氰酸酯(MDI)、1,4-丁二醇(BDO)和亲水性聚乙二醇(PEG)为原料，通过异氰酸酯的氢转移加聚反应，合成了具有不同链段结构的端二异氰酸根聚醚型聚氨酯(OCN-PEU-NCO)，并将其与不同分子量的端二羟基聚醚砜(PES)进行了嵌段反应，考察了反应温度、反应浓度、溶剂种类对嵌段反应的影响，确定了合成反应最佳工艺条件，并用FTIR光谱、DSC谱图对嵌段反应产物(PEU-PES)进行了表征。 采用浊点滴定法测定了PEU-PES三元纺丝液体系的相图，研究了PES分子量、非溶剂及溶剂对聚合物／溶剂／非溶剂三元体系相分离的影响；对聚合物／溶剂／非溶剂／致孔剂四元体系，着重讨论了致孔剂种类及用量对四元相图的影响。这些工作为PEU-PES中空纤维膜纺丝液的配制和纺丝工艺的选择奠定了基础。 分别以二甲基亚砜(DMSO)、二甲基甲酰胺(DMF)、二甲基乙酰胺(DMAC)为溶剂，M=2000、4000的聚乙二醇(PEG)和聚乙烯吡咯烷酮(PVP)为致孔剂配制纺丝液。以水为沉淀剂，采用干喷-湿纺法纺制中空纤维膜，考察了嵌段共聚物(PEU-PES)中PES分子量、溶剂及致孔剂对中空纤维膜结构与性能的影响。研究结果表明：所制得的中空纤维膜，大多均具有内外双致密层、指形非对称结构；改性后的PEU-PES中空纤维超滤膜在透水率、BSA截留率方面均优于未改性的PES膜。 将PEU-PES膜材料自制成中空纤维微超滤器，用于中药丹参药液的超滤，经高效液相色谱(HPLC)测定，其主要有效成份原儿茶醛含量在超滤前后损失率为10.8～18.9％，低于常规水煮醇沉法的损失率(44.6％)。 通过膜的接触角和膜的污染度的测定结果表明，嵌段改性后膜的亲水性有所提高，抗污染性能得到改善。更多还原

【Abstract】 In this dissertation, diisocyanate terminated polyetherurathane (OCN-PEU-NCO) was synthesized with 4,4’-diphenylmethane diisocyanate (MDI), 1,4-butane diol (BDO) and hydrophilic polyethylene glycols (PEG) of different molecular weights. And the PEU of different chain structures was introduced into the chain of polyethersulfone (PES) with different molecular weights through block copolymerization. The effects of reaction temperature, reaction concentration and different types of solvent on the block copolymerization were investigated. Thus the optimal synthesizing technology conditions were determined. The structure of the obtained products was characterized with FTIR spectrum and DSC chart.Phase diagrams of the ternary and the quaternary PEU-PES membrane-forming systems were obtained by cloudpoint titration method. The influences of molecular weight of polyethersulfone, the solvent and the nonsolvent on the phase diagram of the ternary system, polymer/solvent/nonsolvent, were studied. As for the quaternary system, polymer/solvent/nonsolvent/pore-forming additive, the roles of different types of pore-forming additives and their use levels were particularly discussed. As a result of these experiments, some useful ideas on choosing the conditions for PEU-PES hollow fibre membrane preparation and spinning technology were suggested.Membrane-forming solution were prepared, using the PEU-PES segmented copolymers as membrane spinning material, dimethylsulfoxide (DMSO), dimethyl-formamide (DMF), dimethylacetamide (DMAC) as solvents, polyethylene glycols(PEG) and polyvinylpyrrolidone(PVP) as pore-forming additives (PFA). Hollow fiber membranes were spun by dry-jet wet spinning method, using water as nonsolvent. The effects of molecular weight of polyethersulfone, solvent and pore-forming additive on the structure and performance of the hollow fibre membrane were researched. The results obtained show that most of the PEU-PES hollow fiber membranes have asymmetric figure-type structure, which has the outer and inner double skin layers. The pure water fluxes (PWF) and the rejection rate of BSA of modified hollow fibre membranes(PEU-PES) are improved, compared with the unmodified polyethersulfone membrane materials.The self-made hollow fiber ultrafilter was applicated to the component separation of Chinese drug Danshen. The measurement of high performance of liquid chromatography (HPLC) indicated that the loss of the main effective component protocatechuic aldehyde was 10.8-18.9%, which was smaller than that of the traditional water-alcohol-precipitation method. And the results of examining the impurities in the filtrate were also better.By the means of contact angle and fouling rate testing, it showed that the hydrophiliciry of the modified membranes was enhanced, and the function of fouling resistance was also improved, in comparison with the unmodified membrane.更多还原