Methods for study the microscopic properties of droplets in microemulsions by precise measurements of density, refractive index and turbidity have been established. The structural and interaction parameters of droplets in AOT/H2O/toluene microemulsions with molar ratio r of water to surfactant being 10.5 and 12 have been investigated and the molecular length L of AOT has been found to be 1.07 nm. The dependence of phase-separation temperature on r has been discussed in terms of the interaction between droplets. With L=1.07 nm, microscopic structures of droplets of the two microemulsion systems of AOT/H2O/toluene and AOT/H2O/cyclohexane at various values of r have been investigated by measurements of density only. The results are excellently consistent with reported values. It has also been found that the density of water in droplets was significantly larger than that of free water, and was varied with the solvents, while the configuration of AOT molecule kept unvaried.%建立了通过精密测量密度、折射率和浊度研究微乳液滴微观性质的方法,获得水与表面活性剂的摩尔比r分别为10.5和12的AOT/H2O/甲苯微乳液体系液滴的微观结构及相互作用参数,得到AOT分子的长度L=1.07nm,用液滴间的相互作用讨论了相变温度与r的关系.用L=1.07nm,通过密度测量得到AOT/H2O/甲苯和AOT/H2O/环己烷两个微乳液体系不同r值下液滴的微观结构参数,与文献报导的数据吻合得很好.发现在微乳液滴中的水的密度明显大于自由水的密度,并随溶剂变化,而AOT分子的构型不变.
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