靠近第二临界胶束浓度的C_(16)TAB/AS/H_2O系统的胶束聚集数和粘度(英文)  

Micellar Aggregation Numbers and Viscosities of C_(16)TAB/AS/H_2O System Near the Second Critical Micelle Concentration

作　　者：陈燕梅[1] 何少青[1] 贵元香[1] 郝力生[1] 南延青[1] 

机构地区：[1]湖南师范大学化学化工学院,中国长沙410081

出　　处：《湖南师范大学自然科学学报》2013年第1期43-50,共8页Journal of Natural Science of Hunan Normal University

基　　金：国家自然科学基金资助项目(20976042);湖南省自然科学基金资助项目(09JJ001)

摘　　要：浓度处于第一和第二临界胶束浓度(CMC1和CMC2)之间的十六烷基三甲基溴化铵C16TAB水溶液和十二烷基磺酸钠AS水溶液的胶束聚集数N随浓度的增大而线性增大.无机盐的加入导致C16TAB水溶液N的增大.对于x2(阳离子表面活性剂在总表面活性剂中的摩尔分数)=0.7,0.8和0.9的C16TAB/AS/H2O系统,在相同表面活性剂总浓度cT下,N随x2的减小而增大.对于浓度在CMC2附近的这些系统,N随cT的增大而增大,且x2=0.7的复配系统的棒状胶束显现出显著的伸长趋势.C16TAB/AS/H2O系统的粘度随cT的增大表现出类似的变化趋势.无机盐的加入使x2=0.8和0.9的C16TAB/AS/H2O系统的N更大,粘度更高.可是,对于x2=0.7的系统,NaBr的加入却使N减小,使粘度比不加盐的系统先略微高些然后更低些.临界堆积参数,棒状胶束的端盖能(end-cap energy)和Collins的水亲合性匹配的概念被用于解释本文的实验结果.Micellar aggregation numbers N of cetyhrimethylammonium bromide C16 TAB/H2O and sodium dodecylsulfonate AS/H2O systems with concentrations between the first and the second critical micelle concentrations （CMC1 and CMC2 ） increase linearly with increasing concentration. The addition of inorganic salt into C16TAB/H2O systems leads to larger N. For the C16TAB/AS/H2O mixed systems with x2 = 0.7, O. 8 and 0.9 （x2 is the mole fraction of cationic surfactant in the total mixed surfactants）, at the same total suffactant concentration cT, N increases with decreasing x2. For these mixed systems with concentrations near CMC2, N increases with increasing cr, and the rodlike micelles of the mixed systems with x2 =0.7 shows enhanced elongation tendency. Viscosities of the C16TAB/AS/H2O mixed systems show similar changing tendency with cT. The addition of inorganic salt into the C16TAB/AS/H2O mixed systems with x2 = 0.8 and 0.9 leads to larger N and higher viscosities. However, for the mixed systems with x2 = 0.7 near CMC2, the addition of NaBr leads to smaller N, and slightly higher viscosity first and lower viscosity afterwards. Critical packing parameter, end-cap energy of the rodlike micelles and Collins＇ concept of matching water affinities were used to interpret the experimental resuhs.

关 键 词：正负离子表面活性剂 胶束聚集数 粘度 

分 类 号：O648[理学—物理化学]