草酸对非对称膜成膜过程中热力学、流变学和凝胶动力学的影响  

Effect of Oxalic Acid on Rheological Variation,Thermodynamic Variaton and Formation Kinetics in Asymmetric Membrane Formation

作　　者：李昕[1,2] 陈翠仙[2] 李继定[2] 

机构地区：[1]北京理工大学化工与环境学院,北京100081 [2]清华大学化工系,北京100084

出　　处：《高等学校化学学报》2009年第1期203-207,共5页Chemical Journal of Chinese Universities

基　　金：国家"九七三"计划项目(批准号:2003CB615701);中石化科技开发研究基金(批准号:X505002);国家自然科学基金(批准号:20806008);北京理工大学优秀青年教师资助计划(批准号:2006Y0510);北京理工大学校基础研究基金(批准号:20070542006)资助

摘　　要：以酚酞基聚芳醚砜/草酸/N,N-二甲基乙酰胺为铸膜液体系,考察了草酸对非对称膜成膜过程中的热力学、流变学和凝胶动力学的影响.结果表明,草酸的加入,在热力学上加速了铸膜液的相分离.成膜过程中凝胶动力学的研究结果表明,凝胶前锋位移的平方与时间不是简单的线性关系.将凝胶过程与非对称膜的结构相对应,分为4个连续的凝胶过程,凝胶速度曲线由4段具有不同速度常数的线段组成.在凝胶过程中,凝胶速度常数最大的是皮层.The effects of oxalic acid on rheological, thermodynamic and membrane formation kinetics were investigated in polyethersulfone with cardo/oxalic acid（OA）/N,N-dimethylacetamide cast solution. The results show that the addition of OA can work in favor of the enhancement in the demixing of casting solution thermodynamically. The membrane formation kinetics result is different from a commonly accepted conclusion obtained by Strathman et al. that a single linear correlation between square of precipitation front move （ L^2 ） and gelation time （t） existed for the whole gelation process. Four different linear correlations between the value of L^2 and gelation time（t）, were identified, these four correlations correspond to four consecutive gelation steps. The maximal gelation rate constant occurred the top layer.

关 键 词：草酸 非对称膜 热力学 流变学 凝胶动力学 

分 类 号：O631[理学—高分子化学] TQ028.8[理学—化学]