Solubilization of triglycerides in liquid crystals of nonionic surfactant
Solubilization of triglycerides in liquid crystals of nonionic surfactant
复制标题
DOI：
10.1016/j.jcis.2008.05.066
复制
发表时间：
2008-09-01
影响因子：
9.9
通讯作者：
Aramaki, Kenji
中科院分区：
文献类型：
--
作者：
Alam, Mohammad Mydul;Varade, Dharmesh;Aramaki, Kenji
研究了甘油三酯[1,2,3-三丁酰甘油(TBG)和1,2,3-三己酰甘油(THG)l在水/八(氧乙烯)十二烷基醚(C(12)EO(8))体系中的溶解情况。通过光学观察和小角X射线散射（SAXS）测量研究了水/C（12）EO（8）体系中油引起的液晶结构的变化。在水/C(12)EO(8)/油体系中，THG 和 TBG 的溶解会在高 C(12)EO(8) 浓度下诱导 H(1)（六方）和 L(α)（层状）液晶之间的转变，而在低表面活性剂浓度下，会发生 H(1)-I(1)（不连续胶束立方相）转变。这种异常行为归因于胶束中溶解油的分配。在低表面活性剂浓度下，THG 主要溶解到表面活性剂胶束的疏水核心中，表现出高溶胀或低渗透趋势，导致聚集体半径 (r(H)) 急剧增加，从而诱导杆球转变。在高表面活性剂浓度下，THG 主要不溶解到核心中，而是分布在聚集体的栅栏层和核心之间。 TBG 大量溶解到表面活性剂栅栏层中，表明具有高渗透趋势，导致每个表面活性剂分子的有效横截面积 a(s) 增加。 I(1) 相的热稳定性随着 THG 溶解到聚集核中而增加。还评估了 H(1) 和 L(α) 相中不同甘油三酯或不同表面活性剂浓度的实验层间距 (P(d)) 与完全溶胀的百分比偏差。研究发现，甘油三酯的渗透趋势可用作 I(1) 相形成的调节参数，具体取决于表面活性剂浓度和油的分子量。 (C) 2008 Elsevier Inc. 保留所有权利。
The solubilization of triglycerides [1,2,3-tributanoylglycerol (TBG) and 1,2,3-trihexanoylglycerol (THG)l in water/octa(oxyethylene) dodecyl ether (C(12)EO(8)) systems has been investigated. Oil-induced changes in the structure of liquid crystals in water/C(12)EO(8) system have been studied by optical observation and small-angle X-ray scattering (SAXS) measurements. In the water/C(12)EO(8)/oil systems, solubilization of THG and TBG induces a transition between H(1) (hexagonal) and L(alpha) (lamellar) liquid crystals at high C(12)EO(8) concentrations, whereas at low surfactant concentrations a H(1)-I(1) (discontinuous micellar cubic phase) transition occurs. This anomalous behavior is attributed to the partitioning of solubilized oil in the micelles. At low surfactant concentrations THG is mainly solubilized into the hydrophobic cores of the surfactant micelles, indicating high swelling or low penetration tendency, resulting in a steep increase in the radius of the aggregates (r(H)), thereby inducing a rod-sphere transition. At high surfactant concentrations, THG is not mainly solubilized into the core but distributed between the palisade layer and the core of the aggregates. The TBG is considerably solubilized into the surfactant palisade layer, indicating a high penetration tendency, resulting in an increase in the effective cross-sectional area per surfactant molecule, a(s). The thermal stability of the I(1) phase increases with the solubilization of THG into the aggregate cores. The percentage deviation of the experimental interlayer spacings (P(d)) from complete swelling was also evaluated for different triglycerides in the H(1) and L(alpha) phases or different surfactant concentrations. It is found that the penetration tendency of triglycerides could be used as a tuning parameter for I(1) phase formation depending on the surfactant concentration and the molecular weight of the oil. (C) 2008 Elsevier Inc. All rights reserved.