摘要
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.
Polydopamine has properties of strong adhesion and readily formatting covalent bond with-NH2group,therefore was adopted as an interlayer to graft polyvinyl alcohol（PVA）-amino acid copolymer on the surface of polyethersulfone（PES） ultrafiltration membrane. Grafting the copolymer on the polydopamine layer enhanced the hydrophilicity of PES ultrafiltration membrane. In this study,the PVA-amino acid copolymer was formed by the esterification between amino acid and PVA,and grafted on the membrane surface by the covalent bonds between the —NH2group and polydopamine layer which was coated before the grafting step. The modified membranes were evaluated by the measurements of pure water flux test,fourier transform infrared spectrometer（FTIR）,contact angle and field emission scanning electron microscope（FESEM）,and the separation efficiency and anti-fouling ability of the modified membrane to oil /water emulsion was simultaneously investigated. The contact angles of the unmodified membrane was 91°,and decreased to 71° by polydopamine coating and 53° by PVA grafting. The results indicated that the hydrophilicity of membrane surface was improved after modification.In the separation experiment,both the flux in steady-state and cleaning recovery rate of the modified membranes were higher than those without modification.
出处
《环境科学学报》
CAS
CSCD
北大核心
2014年第5期1212-1219,共8页
Acta Scientiae Circumstantiae
基金
国家自然科学基金青年基金项目(No.20906011)
上海市自然科学基金(No.13ZR1401000)~~
