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基于聚合多巴胺的附着性及易与氨基(—NH2)等基团形成共价键的特性,本实验将聚合多巴胺作为对聚醚砜(PES)超滤膜进行表面改性的接枝中间物,将聚乙烯醇(PVA)-氨基酸共聚物接枝至PES膜表面,从而提高PES超滤膜的亲水性能.实验通过PVA与氨基酸的酯化反应形成PVA-氨基酸共聚物,将带有—NH2的共聚物与PES超滤膜表面的聚合多巴胺涂覆层形成共价键,从而将亲水的PVA-氨基酸共聚物接枝到疏水的超滤膜表面.实验利用通量的变化、红外光谱(FTIR)分析、表面接触角、场发射扫描电镜(FESEM)等手段来表征膜特征参数的变化,同时也考察了改性膜对油水乳化液的分离效率和抗污染能力.试验结果表明,经过PVA-氨基酸共聚物接枝改性的膜表面的亲水性有一定的提高,原膜接触角为91°,涂覆和接枝改性后的膜表面接触角分别为71°和53°,油水乳化液的分离实验显示,改性后的膜通量和清洗恢复率均有明显提高.
Based on the properties of polymeric dopamine and covalent bond with amino group (-NH2), poly (D-methylethylene) (PES) was used as the graft intermediate for surface modification of polyethersulfone (PES) Polyvinyl alcohol (PVA) -amino acid copolymer was grafted to the surface of PES membrane to improve the hydrophilicity of PES membrane.Experiment The PVA-amino acid copolymer was formed by the esterification reaction of PVA and amino acid, Of the copolymer with the surface of the PES ultrafiltration membrane dopamine coating formation of covalent bonds, so hydrophilic PVA-amino acid copolymer grafted onto the surface of hydrophobic ultrafiltration membrane experiments using changes in flux, infrared spectroscopy ( FTIR analysis, surface contact angle and field emission scanning electron microscopy (FESEM) were used to characterize the change of membrane characteristic parameters, and the separation efficiency and anti-pollution ability of the modified membrane on oil-water emulsion were also investigated. - amino acid graft modified hydrophilic membrane surface has a certain degree of hydrophilicity, the original membrane contact angle of 91 °, coated and graft modified membrane surface contact angle of 71 ° and 53 °, respectively, oil and water Emulsion separation experiment showed that the modified membrane flux and Cleaning recovery rates have improved significantly.