功能性PVDF膜的制备及性能研究

发布时间：2018-04-28 20:46

本文选题：PVDF + TiO_2纳米粒子　；参考：《天津工业大学》2017年硕士论文

【摘要】：由于分离效率高、无污染、操作方便、节约能源等优点,膜分离技术在许多领域得到了广泛的应用。聚偏氟乙烯是一种常用的膜材料,其具有良好的抗老化性、耐候性、机械性能和耐紫外光辐射及化学稳定性等特性,且不受强酸、强碱和强氧化剂的腐蚀。然而,PVDF表面能低,导致疏水性强,使膜在使用过程中极易受到有机物及微生物的影响,造成膜的污染,降低膜的分离效果和使用寿命,限制了其在多领域中的应用。因此需要对PVDF进行改性,以拓展膜分离过程的工业应用范围。在本课题中分别利用半互穿网络技术将丙烯酸单体和PVDF粉末通过同步合成法制得PVDF/PAA聚合物,将其与二氧化钛溶胶凝胶共混制备PVDF/PAA/Ti02复合膜;利用自聚合反应使盐酸多巴胺在PVDF粉末的表面发生聚合反应,制得PVDF/PDA粉末,通过浸没沉淀相转化法制备PVDF/PDA膜,利用液相沉积法将二氧化钛无机纳米粒子负载在膜的表面和内部,制备PVDF/PDA/Ti02复合膜。本课题对复合膜的表征及测试进行了系统的研究。采用红外光谱(FTIR)、场发射扫描电子显微镜(FESEM)、能谱分析(EDX)、X射线电子光谱(XPS)、接触角测试仪以及紫外可见分光光度计等分析测试手段对制备的复合膜进行表征和测试,分析PVDF改性前后基团的变化和膜表面及内部元素组成,观察膜表面及断面的形貌。结果表明,PAA和PDA成功的对PVDF进行了改性,并提高了 PVDF的亲水性能。TiO2无机纳米粒子均匀的分布在膜内,未发现明显团聚现象,同时其赋予了复合膜良好的自清洁性能。PDA的引入,使TiO2无机纳米粒子在膜的表面大量负载,赋予了复合膜光敏性。复合膜表现出优良的油水分离性能。
[Abstract]:Because of the advantages of high separation efficiency, no pollution, convenient operation and energy saving, membrane separation technology has been widely used in many fields. Polyvinylidene fluoride (PVDF) is a commonly used membrane material. It has good aging resistance, weathering resistance, mechanical properties, UV radiation resistance and chemical stability, and is not corroded by strong acid, strong alkali and strong oxidant. However, the low surface energy of PVDF leads to strong hydrophobicity, which makes the membrane easily affected by organic matter and microorganism in the process of use, resulting in membrane fouling, reducing the separation effect and service life of the membrane, and limiting its application in many fields. Therefore, it is necessary to modify PVDF in order to expand the industrial application of membrane separation process. In this paper, PVDF/PAA polymer was synthesized by syntheses of acrylic acid monomer and PVDF powder by semi-interpenetrating network technology, and PVDF/PAA/Ti02 composite membrane was prepared by blending it with TIO _ 2 sol gel. The PVDF/PDA powder was prepared by self-polymerization of dopamine hydrochloride on the surface of PVDF powder. The PVDF/PDA film was prepared by immersion precipitation phase inversion method. The TIO _ 2 inorganic nanoparticles were loaded on the surface and inside of the film by liquid phase deposition. PVDF/PDA/Ti02 composite membrane was prepared. In this paper, the characterization and test of composite membrane are studied systematically. The composite films were characterized and tested by means of FTIR, field emission scanning electron microscopy (SEM), energy spectrum analysis (EDX), X-ray electron spectroscopy (XPS), contact angle tester and UV-Vis spectrophotometer. The changes of the groups and the composition of the surface and internal elements of PVDF were analyzed, and the morphology of the surface and cross section of the membrane were observed. The results showed that PVDF was modified successfully by PVDF and PDA, and the hydrophilicity of PVDF. TiO2 inorganic nanoparticles were distributed uniformly in the film, no obvious agglomeration was found, and the composite membrane was endowed with good self-cleaning property. PDA was introduced into the composite membrane. The TiO2 inorganic nanoparticles were loaded on the surface of the membrane, which gave Guang Min of the composite membrane. The composite membrane shows excellent oil-water separation performance.
【学位授予单位】：天津工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ051.893

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