The phase behaviour of palm olein (PO) and its derivative oils (palm oil methyl esters and medium chain triglycerides) with Imbentin coco 6.9EO, an ethoxylated C12-14 alcohol, in water has been investigated to identify compositions where microemulsions occur. The techniques used were the optical microscope phase penetration scan and small angle X-ray diffraction (SAXS). Mixed surfactant/oil samples were prepared at wt. ratios of 0.1:1, 0.25:1, 0.5:1 and 1:1 for the phase penetration scan. For SAXS analysis, the initial concentration of surfactant in water (W) was fixed at 38% (w/w), which forms a hexagonal mesophase (H1). Palm oil methyl esters (POME) and medium chain triglycerides (MCT) were added to this at 0.04:1 (or 0.05:1 for MCT), 0.1:1, 0.2:1 (or 0.25:1 for MCT), 0.5:1 and 1:1 ratios of oil to surfactant. Schematic phase diagrams were constructed to document the changes of phase structures using both bulk samples and phase penetration scans techniques. The extent of microemulsion formation (or solubilisation) decreases in the sequence POME > MCT > PO, and increases substantially with temperature, particularly for POME and MCT. All of the oils destabilize the hexagonal phase; for POME and MCT there is an increase in the surfactant cloud point temperature by ca. 10 degrees C or more, but the temperature for the onset of the lamellar (Lalpha) phase dispersion region (W + Lalpha) is hardly affected. There was a pronounced tendency for the lamellar phase formed in the presence of high oil concentrations and low water levels to have a reduced melting point. With the highest MCT levels a bicontinuous cubic phase (probably V2) is present at 25 degrees C, although this phase is not present in the binary surfactant/water system. The X-ray diffraction results show that the average area per head group (ao) at the micelle surface is decreased by the addition of the oils, consistent with the observation of a V2 phase. Possible molecular mechanisms for this observation are discussed.

中文翻译：

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非离子表面活性剂与棕榈油及其衍生物的混合物形成的液晶和微乳液。

已对棕榈油精（PO）及其衍生物油（棕榈油甲酯和中链甘油三酸酯）与Imbentin coco 6.9EO（乙氧基化C12-14醇）在水中的相行为进行了研究，以鉴定发生微乳液的成分。所使用的技术是光学显微镜相渗透扫描和小角度X射线衍射（SAXS）。混合的表面活性剂/油样品以重量计制备。相穿透扫描的比率为0.1：1、0.25：1、0.5：1和1：1。对于SAXS分析，将表面活性剂在水中的初始浓度（W）固定为38％（w / w），形成六方中间相（H1）。将棕榈油甲酯（POME）和中链甘油三酸酯（MCT）以0.04：1（对于MCT而言为0.05：1），0.1：1、0.2：1（对于MCT而言为0.25：1），0.5：1添加到其中油与表面活性剂的比例为1：1。构造了示意性相图，以使用大量样品和相渗透扫描技术记录相结构的变化。微乳液形成（或增溶）的程度按POME> MCT> PO的顺序降低，并随温度而显着增加，特别是对于POME和MCT。所有的油都会破坏六方相的稳定性。对于POME和MCT，表面活性剂的浊点温度增加了约5％。10℃以上，但是层状（Lα）相分散区域（W +Lα）的开始温度几乎不受影响。在高油浓度和低水含量的情况下形成的层状相具有降低的熔点的明显趋势。在最高MCT水平下，尽管温度在二元表面活性剂/水系统中不存在，但在25°C时存在双连续立方相（可能是V2）。X射线衍射结果表明，通过添加油降低了胶束表面每个头基的平均面积（ao），这与观察到的V2相一致。讨论了这种观察的可能的分子机制。