膜分离技术是一门新兴的高新技术，因分离效率高、能量消耗低等特点，已经广泛应用于电力、电子、化工、食品、医药、生物、饮料和环保等领域。分离膜是这一技术的核心，因此膜材料的制备技术成为研究的重点。 双酚A型聚砜（PSF），因其砜基的两边有苯环形成共轭体系，加之硫原子处于最高氧化态，所以PSF具有优良的抗氧化性、热稳定性和高温熔融稳定性。又因为PSF具有优异的机械性能与电性能，所以成为制备分离膜的主要原料之一。但PSF的疏水性导致其抗污性较差、使用周期短。因此，对于PSF的改性成为了当前膜分离技术领域中的重要议题。 近年来，针对PSF的改性方法有涂层法、共混法、接枝法和本体改性法。其中，使用最多的方法是共混法，其原理是将双亲性或亲水性物质作为添加剂加入PSF铸膜液中，然后利用沉淀相转化法制改性聚砜膜。这种方法确实提高了膜的亲水性、水通量和抗污性。但添加剂会使制膜过程复杂化，并且在含水环境中添加剂会释出，使聚砜分离膜膜性能弱化，影响分离膜的使用。因此，开发出一种适于制膜的双亲性聚砜共聚物对于优化分离膜具有重要意义。本论文提出了利用亲水性聚合物聚乙二醇单甲醚（CH3-PEO）改性双酚A型聚砜（PSF）的合成制备方法，利用选择性溶胀诱导成孔技术制备PSF-b-PEO多孔膜并对膜结构进行表征。主要研究结果如下： （一）基于亲核取代反应原理制备高分子量PSF，系统地研究了单体种类、溶剂种类、温度以及聚合时间对PSF分子量的影响。首先考察了单体种类对PSF分子量的影响，分别以4,4’-二氯二苯砜（DCDPS）和4,4’-二氟二苯砜（DFDPS）为单体合成PSF。之后，研究不同反应体系对PSF分子量的影响，确定了三种反应体系，分别为以N, N-二甲基吡咯烷酮为溶剂、以N, N-二甲基乙酰胺为溶剂和以环丁砜为溶剂的反应体系。随后，确定以DFDPS为单体，以环丁砜为溶剂，聚合时间为5 h，探究聚合温度对PSF分子量的影响，分别选取200 ℃、210 ℃和220 ℃为聚合温度合成PSF。通过改变实验条件可以实现分子量范围为20～140 kDa的PSF的控制合成。 （二）基于酚羟基与芳香氟化物中F原子之间的反应，利用亲水性聚合物CH3-PEO与PSF进行反应，两步法制备双嵌段共聚物PSF-b-PEO。通过改变第2步反应的温度、反应时间和CH3-PEO分子量，考察了反应条件对PSF-b-PEO分子量及聚合物中PEO含量的影响。利用选择性溶胀诱导技术制备PSF-b-PEO多孔膜，研究了温度、溶胀时间及混合溶剂组成对膜结构的影响。 （三）在已成功制备PSF-b-PEO的基础上，即利用三步法制备三嵌段共聚物PEO-b-PSF-b-PEO。考察了第3步反应的温度、反应时间和CH3-PEO分子量对PEO-b-PSF-b-PEO的分子量及PEO含量的影响。

Membrane separation is a rising technology, which has been widely used in the fields of electricity, electronics, chemical, food, medicine, biology, beverage and environmental protection, because of its high separation efficiency and low energy consumption. Separation membrane is the core of this technology. The preparation technology of membrane materials has become the focus of the researches. Bisphenol A polysulfone (PSF), which forms a conjugated system on both sides of the sulfone group, and the sulfur atom is in the highest oxidation state, so PSF has excellent oxidation resistance, thermal stability and high temperature melting stability. Because of its excellent mechanical and electrical properties, PSF is one of the main raw materials for preparing separation membranes. However, the hydrophobicity of PSF leads to its poor antifouling property and short-life. Therefore, the modification of PSF has become an important topic in the field of membrane separation technology. In recent years, the modification methods for PSF include coating, blending, grafting and bulk modification. The most commonly used method is blending. The principle is to add the amphiphilic or hydrophilic substance as additive to the PSF casting solution, and preparation modified polysulfone membrane by precipitation phase transformation. This method improves the hydrophilicity, water flux and antifouling of the PSF membrane, but the additive make the film making process complicated, and the leakage of additives in wet environment makes the performance of modified PSF membrane weak and influence the use of separation membrane. Therefore, the development of an amphiphilic polysulfone copolymer suitable for membrane preparation is of great significance for optimizing separation membranes. In this work, a synthetic preparation method with using hydrophilic polymer (CH3-PEO) modified PSF was proposed, and the PSF-b-PEO porous membrane was prepared by selective swelling induction pore-forming technique, and then the membrane structure was characterized. The main results are as follows: (1) Based on the principle of nucleophilic substitution reaction, high molecular weight PSF is prepared. The effects of the type of monomer, the type of solvent, the polymerization temperature and time on the molecular weight of PSF are systematically studied. Firstly, the influence of monomer species on the molecular weight of PSF is studied. Bis(4-chlorophenyl) sulphone (DCDPS) and bis(4-fluorophenyl) sulfone (DFDPS) are used as monomer to polymerized PSF respectively. Then the influence of different reaction systems on the molecular weight of PSF is studied, three reaction systems are determined, including N, N-dimethyl pyrrolidone (NMP), N, N-dimethyl acetamide (DMAc) and tetramethylene sulfone (TMS) as solvent. Then, the effect of polymerization temperature on the molecular weight of PSF is investigated with DFDPS as a monomer, TMS as solvent and polymerization time of 5h. The polymerization temperature is selected for polymerization of PSF at 220 ℃, 210 ℃and 220 ℃. By changing the experimental conditions, the molecular weight of PSF can be obtained from 20 kDa to 140 kDa. (2) Based on the organic reaction principle between -OH and -F, hydrophilic polymer CH3-PEO is used to modify PSF, and block copolymer PSF-b-PEO is prepared by two-step method. The effects of different reaction conditions on the molecular weight and CH3-PEO content of PSF-b-PEO are studied by changing the second step reaction temperature, reaction time and CH3-PEO molecular weight. PSF-b-PEO separation membrane is prepared by selective swelling induction, and the effects of different temperatures, soaking time and proportions of mixed solvents on the structure of the membrane are studied. (3) Based on the successful preparation of PSF-b-PEO, another CH3-PEO modified polysulfone is synthesized, that is, the three block copolymer PEO-b-PSF-b-PEO is prepared by three-step method. After that, the effects of different reaction conditions on the molecular weight and CH3-PEO content of PEO-b-PSF-b-PEO are studied by changing the third step reaction temperature, reaction time and CH3-PEO molecular weight.