| 两性离子在聚偏氟乙烯(PVDF)膜表面接枝改性的研究 |
| 摘要点击 2867 全文点击 1664 投稿时间：2012-12-21 修订日期：2013-04-09 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 PVDF膜 接枝改性 亲水性 抗污染能力 通量恢复率 通量比 膜阻力 |
| 英文关键词 PVDF membrane graft modification hydrophilicity anti-pollutaion performance flux recovery ratio flux ratio membrane resistance |
|
| 中文摘要 |
| 为增强膜的亲水性,提高抗污染能力,采用原子转移自由基反应(ATRP),将甲基丙烯酸羟乙酯(HEMA)接枝到聚偏氟乙烯(PVDF)膜表面; 再以硝酸铈铵(CAN)为引发剂,N,N'-亚甲基双丙烯酰胺(MBAA)为交联剂,通过自由基聚合反应将两性离子单体3-(甲基丙烯酰胺基)丙基-二甲基(3-硫代丙基)氢氧化铵内盐(MPDSAH)成功接枝到膜表面. 采用全反射红外光谱仪(ATR-FTIR)、X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)以及接触角测定仪分析了改性前后膜表面性质及结构形态变化. 随接枝时间的增加,接枝密度(GD)逐渐升高,膜孔径变小,孔隙率降低,但同时膜表面亲水性明显增强. 通过牛血清蛋白(BSA)吸附及过滤实验,检验PVDF膜改性前后的抗污染性能. 随着GD的增加,在高浓度BSA溶液中膜表面吸附量明显减少. 当GD为288.340 μg·cm-2时,膜表面接触角(CA)降低最多,由原膜的77.2°降至41.7°,且在5 s内降为0,通量恢复率高达94.961%. 因此,最佳接枝时间为2 h,此时接枝密度288.340 μg·cm-2则是最佳接枝密度. |
| 英文摘要 |
| In order to enhance the hydrophilicity of the membrane and improve the antifouling properties, poly(2-hydroxyethyl methacry-late) (poly(HEMA)) was grafted to the surface of the poly(vinylidene fluoride) (PVDF) membrane by using the atom transfer radical polymerization (ATRP) method. After that, ceric ammonium nitrate (CAN) as the initiator, N,N'-methylene bisacrylamide as a cross-linking agent, a zwitterionic polymer, poly(3-(methacryloylamino) propyl-dimethyl-(3-sulfopropyl) ammonium hydroxide) (poly(MPDSAH)) were successfully grafted onto the membrane surface by radical polymerization reaction. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and contact angle measuring were employed to analyze the property and the morphology of structures before and after the membrane surface-modification. The grafting density (GD) gradually increased, with the grafting time increasing, the pore size of the membrane became smaller, and the porosity decreased, but the surface hydrophilicity of membrane was significantly enhanced at the same time. The adsorption of bovine serum albumin (BSA) tests and filtration experiments were carried out to investigate anti-fouling performances of membrane before and after modification. With the GD increasing, the amount of adsorption on the film surface significantly reduced in the high-concentration BSA solution. The water contact angle (CA) decreased most, from 77.2° to 41.7° within 5 s to 0, and a flux recovery ratio up to 94.961%, when the GD reached 288.340 μg·cm-2. Therefore, the optimal grafting time was 2 h, with the grafting density of 288.340 μg·cm-2. |
|
|
|
