论文部分内容阅读
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。
The self-assembly behavior of surfactant Cetyltrimethylammonium bromide (CTAB) at the oil / water interface was modeled at the mesoscopic level using the Dissolved Particle Dynamics (DPD) simulation method. The effects of surfactant concentration , Oil-water ratio and shear stress on the interfacial tension, tail-tail distance and oil-water interface thickness. The results showed that the increase of oil-water ratio could significantly reduce the oil-water interfacial tension of CTAB and increase the interfacial activity of CTAB. In the presence of shearing, the aggregation behavior of surfactants at the interfacial surface obviously changed, Order decreases, leading to tail-tail distance decreases, the interface thickness increases, the interface efficiency is significantly reduced. The simulation shows that the mesoscopic simulation method can be used as a supplement to the experiment to provide the necessary microscopic molecular structure information for the experiment.