UNASSIGNED: The distribution of surfactants between the water/oil interfaces was investigated using single droplet diffusion experiments and simulation of equilibrium surfactant density profiles. The stability of the interfaces against coalescence was characterized by dye transport in a leach cell and coalescence time of single droplets in a model experiment. The conformation of the surfactants at an interface was then examined via surface rheology, sum frequency generation spectroscopy, and dissipative particle dynamics simulation.
RESULTS: Two selected hydrophilic surfactants combined with a lipophilic surfactant induce very different properties at water/oil interfaces and different dye release behaviour from their corresponding double emulsions. Competitive adsorption of sodium dodecyl sulfate and lipophilic surfactant results in the improvement of encapsulation efficiency, elasticity of the interface, and resistance against coalescence due to the intercalation of surfactant alkyl chains into the oil chains.
UNASSIGNED:使用单液滴扩散实验和平衡表面活性剂密度分布的模拟研究了表面活性剂在水/油界面之间的分布。在模型实验中,通过浸出池中的染料运输和单个液滴的聚结时间来表征界面对聚结的稳定性。然后通过表面流变学检查界面处表面活性剂的构象,和频率产生光谱,和耗散粒子动力学模拟。
结果:两种选择的亲水性表面活性剂与亲脂性表面活性剂组合在水/油界面处诱导非常不同的性质和从其相应的双重乳液中的不同的染料释放行为。十二烷基硫酸钠和亲油性表面活性剂的竞争吸附导致封装效率的提高,界面的弹性,以及由于表面活性剂烷基链插入油链而对聚结的抗性。