介观模拟研究环境因素对油/水界面处十六烷基三甲基溴化铵自组装行为的影响  

Mesoscopic Simulation Study of the Effects of Environmental Factors on the Self-assembly of Cetyltrimethylammonium Bromide at Oil/Water Interface

作　　者：李一鸣[1] 孙暖暖[1] 郭营艳[1] 王东翔[1] 

机构地区：[1]海洋化学理论与工程技术教育部重点实验室中国海洋大学,青岛266100

出　　处：《化学通报》2012年第9期814-814,共1页Chemistry

摘　　要：采用耗散颗粒动力学(DPD)模拟方法在介观层次上模拟了表面活性剂十六烷基三甲基溴化铵(CTAB)在油/水界面的自组装行为,考察了表面活性剂浓度、油水比例以及剪切力等环境因素对表面活性剂界面张力、尾-尾间距离及油水界面厚度的影响。结果发现,油水比例增大可显著降低CTAB存在的油水界面张力,提高CTAB的界面活性;有剪切存在时,表面活性剂在界面的聚集行为明显改变,分子在界面处的排列变得混乱,有序性降低,导致尾-尾间距离减小、界面厚度增加,界面效率显著降低。模拟表明,介观模拟方法可以作为实验的一种补充,为实验提供必要的微观分子结构信息。Self-assembly behaviors of cetyltrimethylammonium bromide （CTAB） adsorbed at the oil/water interface had been studied on a mesoscopic level by using dissipative particle dynamics （DPD） simulation. The effects of environmental factors such as oil/water ratio, shear force and concentration of the surfaetant on the properties of CTAB at the oil/water interface were investigated. The results showed that interracial tension is significantly decreased as an increase in the oil/water ratio but the surface activity improved; lower shear force can obviously change the interracial aggregation of CTAB, so that the surfactant molecules at the interface become unordered, the root mean square end-to-end distance decreases, the interracial thickness increases and the interface efficiency significantly reduce. These phenomena showed that the DPD method can be used as an adjunct to the experiments and can provide the necessary information for experiments on the mierostruetural properties of molecular structures.

关 键 词：介观模拟 表面活性剂 环境因素 油水界面 

分 类 号：O621.2[理学—有机化学]