聚偏氟乙烯膜亲水性研究

发布时间：2018-03-21 17:09

  本文选题：聚偏氟乙烯　切入点：碘转移聚合　出处：《济南大学》2015年硕士论文　论文类型：学位论文

【摘要】：聚偏氟乙烯(PVDF)是一种表观呈白色粉末或颗粒状的聚合物,具有的特征为机械强度较高,耐辐射性能优异,化学稳定性好,在常温条件下耐酸碱侵蚀,但是在实际应用过程中由于C-F键的强烈的疏水疏油性质,导致PVDF膜极易在处理各种水废液中产生分离效率低、吸附污染等问题,所以对聚偏氟乙烯膜的亲水性改性就显得极为重要。论文的主要研究内容为通过合成一种亲水性的嵌段共聚物采用物理共混的方法对聚偏氟乙烯膜进行了亲水性改性,制备出了亲水性良好的聚偏氟乙烯膜。首先,我们采用沉淀聚合的方法以使用三氟三氯乙烷(F-113)作为溶剂,以过氧化苯甲酰(BPO)为引发剂,以全氟碘丁烷(TI-4)为碘转移剂,在高压反应釜进行反应,通过红外、核磁的表征证明合成了大分子碘转移剂C4F9-PVDF-I。其后使用溶液聚合的方法以自制的C4F9-PVDF-I为大分子的碘转移剂,以N,N-二甲基甲酰胺为(DMF)溶剂,以过氧化苯甲酰(BPO)为引发剂制备出了二嵌段共聚物PVDF-b-PtBA。通过使用FT-IR光谱检测在2800-3000cm-1 cm-1处以及1734cm-1处出现的吸收峰证明了-C=O以及-CH-伸缩振动吸收峰,同时使用1H NMR光谱对嵌段共聚物PVDF-b-PtBA进行了结构表征,使用电子扫描显微镜(SEM)研究了合成的嵌段共聚物PVDF-b-PtBA的自组装行为,并观察到了嵌段共聚物PVDF-b-PtBA自组装的成球现象。使用合成的嵌段共聚物PVDF-b-PtBA、聚偏氟乙烯树脂、聚乙二醇(PEG-400)以N、N-二甲基甲酰胺为溶剂配置出铸膜液。使用铸膜液以相转化法制备出了亲水性的偏氟乙烯膜;使用接触角测量仪对制备的亲水性的聚偏氟乙烯膜进行了亲水性测试,经过处理后的的PVDF膜对水的接触角的膜从94.7°下降到58.5°;使用TGA的方法对亲水性聚偏氟乙烯膜进行了热稳定性的测试,亲水性PVDF膜的热分解温度有了较大的提高,分解温度达到260℃以上;亲水性PVDF膜的机械强度达到19MPa;SEM测试结果表明亲水改性PVDF膜的表面存在凹凸不平的孔洞。实验结果表明成功合成了碘转移剂C4F9-PVDF-I,并利用此碘转移剂C4F9-PVDF-I合成了二嵌段共聚物PVDF-b-PtBA,使用嵌段共聚物PVDF-b-PtBA对聚偏氟乙烯膜进行了亲水性改性,表明改性的PVDF膜的亲水性能有很大的提高。
[Abstract]:Polyvinylidene fluoride (PVDF) is an apparent white powder or granular polymer, characterized by high mechanical strength, excellent radiation resistance, good chemical stability, and resistance to acid and alkali erosion at room temperature. However, due to the strong hydrophobic and oil hydrophobic properties of C-F bond in practical application, the PVDF membrane is prone to low separation efficiency and adsorption pollution in the treatment of various kinds of waste water. So the hydrophilic modification of PVDF membrane is very important. The main research content of this paper is to synthesize a hydrophilic block copolymer and physical blending method to modify PVDF membrane hydrophilic. The hydrophilic poly (vinylidene fluoride) membrane was prepared. Firstly, we used precipitation polymerization method to use trichlorotrichloroethane (F-113) as solvent, benzoyl peroxide (BPO) as initiator and perfluoroiodobutane butyrate (TI-4) as iodine transfer agent. The reaction was carried out in a autoclave. It was proved by IR and NMR characterization that the macromolecular iodine transfer agent C4F9-PVDF-Iwas synthesized. After that, the self-made C4F9-PVDF-I was used as the macromolecular iodine transfer agent, and the NN-dimethylformamide was used as the DMF solvent. Diblock copolymer PVDF-b-PtBA was prepared by using benzoyl peroxide (BPO) as initiator. The absorption peaks at 2800-3000cm-1 cm-1 and 1734cm-1 were determined by FT-IR spectroscopy. At the same time, the structure of block copolymer PVDF-b-PtBA was characterized by 1H NMR spectroscopy, and the self-assembly behavior of block copolymer PVDF-b-PtBA was studied by electron scanning microscope (SEM). The ball-forming phenomenon of block copolymer PVDF-b-PtBA self-assembly was observed. PVDF-b-PtBA, polyvinylidene fluoride resin, were used as block copolymers, polyvinylidene fluoride (PVDF-b-PtBA). PEG-400) the hydrophilic vinylidene fluoride (VDF) membrane was prepared by phase inversion method with NN- dimethylformamide as solvent. The hydrophilic polyvinylidene fluoride (PVDF) membrane was tested by contact angle measuring instrument. The contact angle of the treated PVDF membrane to water decreased from 94.7 掳to 58.5 掳, the thermal stability of the hydrophilic polyvinylidene fluoride membrane was tested by TGA method, and the thermal decomposition temperature of the hydrophilic PVDF membrane was improved greatly. The decomposition temperature is above 260 鈩，

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