电导法研究十六烷基三甲基溴化铵在二肽-水混合溶剂中的胶束化行为  

Conductance Studies on the Behavior of Micellization for Cetyltrimetyl Ammonium Bromide in Aqueous Dipeptide Solutions

作　　者：陆艳琦[1,2] 王晓兰[1] 颜振宁[1] 李宇[1] 陶燕[1] 但俊英[1] 

机构地区：[1]郑州大学化学系,河南郑州450001 [2]郑州铁路职业技术学院药学系,河南郑州450052

出　　处：《郑州大学学报（理学版）》2010年第4期71-74,120,共5页Journal of Zhengzhou University:Natural Science Edition

基　　金：国家自然科学基金资助项目;编号20973158;J0830412;河南省杰出青年基金资助项目;编号074100510022;河南省自然科学基金资助项目;编号102300410051

摘　　要：采用电导法测定了不同温度下十六烷基三甲基溴化铵(CTAB)在二肽-水混合溶剂中的电导率,计算得到CTAB在这些体系中的临界胶束浓度和胶束化热力学函数.结果表明,二肽-水混合溶剂中CTAB的临界胶束浓度受温度和加入的二肽浓度的影响.二肽的存在增加了CTAB的表面活性,使其临界胶束浓度减小;胶束化过程的自由能变ΔGom均为负值,表明CTAB在二肽-水混合溶剂中的胶束化过程是自发进行的;ΔHom对自由能变ΔGom的贡献相对于(-TΔSom)对自由能变ΔGom的贡献小很多,胶束化过程为熵驱动过程,且存在焓-熵补偿效应.The electrical conductivity of the cetyltrimetyl ammonium bromide （CTAB） ＋ dipep- tide ＋ water ternary systems is measured at different temperatures. The values of critical micel- lar concentration（corn）,and the thermodynamic function of micellization are obtained. The results show that the Ccm values in aqueous dipeptide solutions are influenced by the temperature and the concentration of dipeptide. The surface activity of CTAB is enhanced by dipeptide, as a result the value of Ccm decreases. The free energy of micellization is negative in the presence of dipeptides, which indicates that micelle formation is a thermodynamically favorable process. Since the contri- bution of △H0 to △Gm is smaller than that of （--T△Sm） to △Gm, the micellization process is an entropy-driven process,and an enthalpy-entropy compensation effect is found in the micellization process.

关 键 词：电导 十六烷基三甲基溴化铵 二肽一水混合溶剂 临界胶束浓度 胶束化热力学函数 

分 类 号：O645.11[理学—物理化学]