Alcohol as tuning parameter in an IL-containing microemulsion: The quaternary system EAN–n-octane–C12E3–1-octanol
Alcohol as tuning parameter in an IL-containing microemulsion: The quaternary system EAN–n-octane–C12E3–1-octanol
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DOI：
10.1016/j.colsurfa.2015.12.021
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发表时间：
2016-04
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通讯作者：
Jan C Thater;T. Sottmann;C. Stubenrauch
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文献类型：
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作者：
Jan C Thater;T. Sottmann;C. Stubenrauch
通过适当的调节参数，可以迫使微乳液发生相转化，即反转两亲膜的曲率。在由水、烷烃和非离子烷基聚乙二醇醚 (CiEj) 组成的微乳液中，温度是一个合适的参数，因为表面活性剂头基会随着温度的升高而脱水。最近，我们能够证明这也适用于硝酸乙铵 (EAN)-正烷烃-CiEj 系统。然而，温度敏感性较弱，这就是为什么我们决定使用疏水性辅助表面活性剂在含有 EAN 的微乳液中诱导相转化。我们研究了四元系统 EAN-n-辛烷-C12E3−1-辛醇作为温度 = 15°C 时酒精浓度的函数，并发现了与水相对应物相同的趋势。 (1) 研究作为酒精含量 (δ) 和表面活性剂总浓度 (γ) 函数的相行为，发现相界类似于鱼的形状。 (2)测量IL相和富油相之间的界面张力σ，观察到在三相区域的中心有最小值。 (3) NMR自扩散测量揭示了从EAN包油微乳液到双连续微乳液并最终到油包EAN微乳液的转变。
With an appropriate tuning parameter a microemulsion can be forced to undergo a phase inversion,i.e.to invert the curvature of the amphiphilic film. In microemulsions consisting of water, ann-alkane and a nonionic alkyl polyglycolether (CiEj) temperature is an appropriate parameter since the surfactant head groups dehydrate with increasing temperature. Recently we were able to show that this also holds true for ethylammonium nitrate (EAN)–n-alkane–CiEjsystems. However, the temperature sensitivity is weaker which is why we decided to use a hydrophobic cosurfactant to induce a phase inversion in the EAN-containing microemulsion. We studied the quaternary system EAN–n-octane–C12E3− 1-octanol as a function of the alcohol concentration atT= 15 °C and found the same trends as for the aqueous counterparts. (1) Studying the phase behavior as a function of the alcohol content (δ) and of the total surfactant concentration (γ), one finds that the phase boundaries resemble the shape of a fish. (2) Measuring the interfacial tensionσbetween the IL- and oil-rich phase, one observes a minimum in the center of the three-phase region. (3) NMR self-diffusion measurements reveal a transition from an oil-in-EAN microemulsion to a bicontinuous microemulsion and finally to an EAN-in-oil microemulsion.