摘要
以聚偏氟乙烯(PVDF)为原料,无机层状材料蒙皂石(MMT)为添加剂,通过溶胶-凝胶相转化法研制成PVDF/MMT超滤膜。考察了MMT质量分数在0%～9%范围内对铸膜液黏度、膜孔隙率、孔径、水通量、PEG20000截留率等性能的影响,以及相图和DSC曲线的变化。实验结果表明,MMT的加入使铸膜液的黏度增加,铸膜液呈现非牛顿流体中的假塑性流体的特性;当MMT加入质量分数为7%时,PVDF/MMT超滤膜水通量可达94.32L·m-2·h-1,对PEG20000的截留率达95.2%。MMT的添加对成膜过程也有影响,从相图分析,加入MMT改变了液–固双节点的位置,铸膜液对非溶剂的容纳能力降低;而从DSC测试曲线得知PVDF/MMT膜的结晶度低于PVDF膜。
Using polyvinylidene fluoride （PVDF） as raw material and the inorganic stratiform material, montmorillonite （MMT）, as additive, the ultrafiltration membrane PVDF/MMT was prepared by L-S phase inversion method. The effects of added MMT concentration （from 0%（wt） to 9%（wt）） on the viscosity and the phase diagram of the membrane casting liquid system and the properties of the prepared membrane （such as the porosity, the pore size, the water flux and the PEG20000 trapped ratio of the membrane） were studied. The results show that the addition of MMT causes a strong viscosity increase of the membrane casting liquid and makes that the casting liquid turns to be non-Newtonian liquid and exhibits the characteristic of the pseudoplastic fluid. When 7%（wt） of MMT was added, the prepared membrane has its pure water flux ability of 94.32L·m^-2·h^-1 and its PEG20000 trapped ratio of 95.2%. It could be seen from the cloud point phase diagram that the MMT addition has some influence on the membrane formation, it changes the position of liquid-solid binode point, and which decreases the water tolerance of the casting liquid. The results of the DSC curves show that the crystallinity of the PVDF/MMT membrane is lower than that of the PVDF membrane without addition of MMT.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2008年第6期1037-1042,共6页
Journal of Chemical Engineering of Chinese Universities
基金
新疆大学基金项目(070196)
关键词
聚偏氟乙烯
蒙皂石
超滤膜
相图
polyvinylidene fluoride （PVDF）
MMT
ultrafiltration membranes
phase diagram
