We have studied concentrated phases of Aerosol OT (AOT) in polar (water, ethylene glycol, formamide, N,N-dimethylformamide) and apolar (isooctane) solvents. We investigated two surfactant volume fractions (φ = 0.2 and φ = 0.6) with small angle x-ray scattering (SAXS), rheology and electrical conductivity experiments. AOT self-assembles differently depending on solvent type and concentration. SAXS experiments show that the AOT/water system displays a lamellar phase. In the other cases, only formamide displays a lamellar phase for φ = 0.6. The other solvents (and formamide at φ = 0.2) promote the self-assembly of AOT in other microstructures. The SAXS spectra display correlation peaks consistent with a disordered array of cylindrical aggregates. The microstructure of the AOT/isooctane system at φ = 0.2 is that of an arrangement of spherical aggregates. The results are explained in terms of surfactant packing models and solvent properties. For instance, the ability of ethylene glycol to form hydrogen bonds with AOT promotes the formation of cylindrical aggregates by increasing the area per surfactant polar head. As N,N-dimethylformamide is slightly miscible in hydrocarbons it increases the volume of the surfactant tail promoting reverse structures.

中文翻译：

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离子表面活性剂 (Aerosol OT) 在极性溶剂中的浓缩相

我们研究了气溶胶 OT (AOT) 在极性（水、乙二醇、甲酰胺、N、N-二甲基甲酰胺）和非极性（异辛烷）溶剂中的浓缩相。 我们通过小角度 X 射线散射 (SAXS)、流变学和电导率实验研究了两种表面活性剂体积分数（φ  = 0.2 和φ = 0.6）。AOT 的自组装因溶剂类型和浓度而异。SAXS 实验表明 AOT/水系统呈现层状相。在其他情况下，只有甲酰胺在φ  = 0.6 时显示层状相。其他溶剂（和φ处的甲酰胺 = 0.2) 促进 AOT 在其他微结构中的自组装。SAXS 光谱显示与圆柱形聚集体的无序阵列一致的相关峰。AOT/异辛烷体系在φ  = 0.2 时的微观结构是球形聚集体的排列。结果根据表面活性剂填充模型和溶剂性质进行了解释。例如，乙二醇与 AOT 形成氢键的能力通过增加每个表面活性剂极性头的面积来促进圆柱形聚集体的形成。由于N，N-二甲基甲酰胺在烃类中略微混溶，它增加了表面活性剂尾部的体积，从而促进了反向结构。