Méndez-Bermúdez Jose G, Dominguez Hector
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, México, D.F., 04510, México.
Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T1Z4, Canada.
J Mol Model. 2016 Jan;22(1):33. doi: 10.1007/s00894-015-2904-x. Epub 2016 Jan 15.
Coarse-grained dynamical simulations have been performed to investigate the behavior of a surfactant micelle in the presence of six different alcohols: hexanol, octanol, decanol, dodecanol, tetradecanol, and hexadecanol. The self-assembly of sodium dodecyl sulfate (SDS) is modified by the alcohol molecules into cylindrical and bilayer micelles as a function of the alcohol/SDS mass ratio. Therefore, in order to understand, from a molecular point of view, how SDS and alcohol molecules self-organize to form the new micelles, different studies were carried out. Analysis of micelle structures, density profiles, and parameters of order were conducted to characterize the shape and size of those micelles. The density profiles revealed that the alcohol molecules were located at the water-micelle interface next to the SDS molecules at low alcohol/SDS mass ratio. At high alcohol/SDS mass ratios, alcohol molecules moved to the middle of the micelle by increasing their size and by producing a structural change. Moreover, micelle structures and sizes were influenced not only by the alcohol/SDS mass ratio but also by the order of the SDS and alcohol tails. Finally, the size of the micelles and enthalpy calculations were used as order parameters to determine a structural phase diagram of alcohol/SDS mixtures in water. Graphical Abstract Structural transition of SDS/alcohol mixtures.
已进行粗粒度动力学模拟，以研究表面活性剂胶束在六种不同醇类（己醇、辛醇、癸醇、十二醇、十四醇和十六醇）存在下的行为。十二烷基硫酸钠（SDS）的自组装被醇分子根据醇/SDS质量比改性为圆柱形和双层胶束。因此，为了从分子角度理解SDS和醇分子如何自组织形成新的胶束，开展了不同的研究。对胶束结构、密度分布和有序参数进行了分析，以表征这些胶束的形状和大小。密度分布表明，在低醇/SDS质量比下，醇分子位于SDS分子旁边的水-胶束界面处。在高醇/SDS质量比下，醇分子通过增大其尺寸并产生结构变化而移动到胶束中间。此外，胶束结构和大小不仅受醇/SDS质量比的影响，还受SDS和醇尾部的有序性影响。最后，胶束大小和焓计算用作有序参数，以确定水中醇/SDS混合物的结构相图。图形摘要：SDS/醇混合物的结构转变。
