乙醇-水溶液中十六烷基三甲基溴化铵的自组装特性  

Self-Assembly of Surfactant Cetyl Trimethylammonium Bromide in Ethanol/Water Mixtures

作　　者：李韡[1] 张铭[1] 张金利[1] 韩永才[1] 

机构地区：[1]天津大学化工学院,天津300072

出　　处：《天津大学学报》2006年第1期5-9,共5页Journal of Tianjin University(Science and Technology)

基　　金：国家自然科学基金资助项目(20206023)中石化股份公司科技基金资助项目(X502012).

摘　　要：为了研究乙醇-水混合溶液中表面活性剂的自组装特性对多孔无机材料模板法合成的作用,采用稳态荧光法测定了乙醇-水混合溶剂的组成变化对十六烷基三甲基溴化铵(CTAB)临界胶束浓度的影响．结果表明,随着乙醇含量的增加,临界胶束浓度值增大;CTAB在水中的临界胶束浓度值为0．000 9 mol／L,而在乙醇中为0．24 mol／L．进而利用耗散颗粒动力学模拟研究了CTAB在水及乙醇-水混合溶剂中聚集形态的转变过程,并利用分子动力学方法计算了CTAB尾基与溶剂分子间的相互作用能,结果表明,CTAB的疏水尾基与乙醇分子之间的相互作用强,因而CTAB在乙醇中不易形成胶束,这与测定的实验数据的规律性一致．To investigate the effect of surfactant self-assembling properties on the template synthesis of porous inorganic materials, the critical micelle concentration （CMC） of surfactant cetyl trimethylammonium bromide （CTAB） was measured in both water and aqueous ethanol solvent using steady-state fluorescence techniques. Results indicated that the CMC increased with the increase of ethanol concentration in the solvent. The CMC value of CTAB is 0. 000 9 mol/L in water, while the value is 0.24 mol/L in ethanol. Further more, the dissipative particle dynamics was adopted to simulate the aggregation of CTAB in water and ethanol/water mixtures. And the energy difference was calculated for the surfactant tail groups after CTAB mixing with the solvent. The simulation results reflected the similar regulations with those experimental data, i.e. , tail groups of CTAB interacted more strongly with ethanol rather than water, which elucidates the reason why the micelle is difficult to form in ethanol solvents.

关 键 词：耗散颗粒动力学 十六烷基三甲基溴化铵 胶束 

分 类 号：O648[理学—物理化学]