摘要
以1-正辛基-3-甲基咪唑六氟磷酸盐[C8mim][PF6]作为膜结构控制剂,采用相转化法制备具有不同孔结构的聚砜分离膜.随着[C8mim][PF6]含量的增大,聚砜膜的孔结构从典型的不对称指状孔结构、高度拉长的大孔结构、典型的大空穴,变化至海绵状孔结构,离子液体[C8mim][PF6]在聚砜膜制备中表现出孔结构控制、增塑作用.通过能谱分析表明,[C8mim][PF6]在所制备的聚砜膜中存在部分的保留,通过水与聚砜膜表面接触角的测定,[C8mim][PF6]在聚砜膜中的残留提高了膜的亲水性能.基于相分离过程的基本理论,探讨了疏水性[C8mim][PF6]在铸膜液相分离过程中孔结构形成的作用机理.研究表明,[C8mim][PF6]在铸膜液中含量越高,对于相分离的延时效应越大,体系更易发生延时分相.
Ionic liquid1-（n-Octyl）-3-Methyl limidazolium hexfluorophosphate [C8mim][PF6]was used as a structure-controlling additive,and polysulfone （PSF） membranes with different structures were prepared by the wet-phase-inversion in this work. The results indicated that ionic liquid [C8mim][PF6 ] had important influence on the pore-forming. With increase of concentration of ionic liquid [C8mim][PF6 ] in casting solutions,the structures of the membranes changed from asymmetric finger pore,the lengthened-big pore and the big caves to spongy pore. When the concentration of [C8mim][PF6 ]was 4% ,the membrane had the asymmetric finger-pores structure,the pore size close to its surface layer was about 2 ～ 6 μm and that close to its sublayer was about 10 ～ 70 μm,the retention rate and flux of PEG10000 were 92. 3% and 33. 7 L·h -1 m -2. The analysis indicated that hydrophobic ionic liquid [C8mim][PF6]could improve orderly arrangement of polysulfone molecules at the low concertration,while the strong delay of phase inversion appeared at the high concertration. It was found by X-ray EDS analysis of PSF membranes with SEM,ionic liquid [C8mim][PF6 ] was partially retained in the prepared polysulfone membrane. This reduced the contact angles between water and polysulfone membranes,improving the hydrophilic properties of the membranes. Meanwhile,the formation mechanism of pore structures in the membrane preparation was also discussed,[C8mim][PF6]could restrain demixing of the casting solutions as a pore-forming agent and plasticizer.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2010年第11期1299-1305,共7页
Acta Polymerica Sinica
基金
陕西省自然科学基础研究计划(项目号2007K071)资助项目
关键词
疏水性离子液体
聚砜膜
结构控制
致孔剂
Hydrophobic ionic liquid
Polysulfone membrane
Structure-controlled
Pore-forming agent
