Beauty Care Research Laboratories, Kao Corporation, Ltd., 2-1-3 Bunka, Sumida-ku, Tokyo, 131-8501 Japan.
Langmuir. 2010 Feb 16;26(4):2430-7. doi: 10.1021/la902905b.
A stable nanoemulsion consisting of nanometer-sized oil droplets in water having a self-standing capability was prepared by high-pressure emulsification. The nanoemulsion does not flow and has a yield stress. This nonfluidity is ascribed to the crystal-like lattice structure of nanodroplets. The lattice structure was observed by transmission electron microscopy of a freeze-fractured surface of the specimen. Small-angle neutron scattering (SANS) revealed the presence of an ordered structure in addition to spherical domains with a radius of 17 nm. This long-range order is, in principle, due to electrostatic repulsive interaction between charged nanodroplets. Dynamic light scattering (DLS) showed two relaxation modes, one for the collective motion of the lattice and the other for the translational diffusion of the nanodroplets. Dilution of the nanoemulsion resulted in a transition from a crystal-like structure to a typical colloidal solution.
通过高压乳化制备了一种由纳米尺寸油滴在水中组成的具有自立能力的稳定纳米乳液。纳米乳液不流动并有屈服应力。这种非流动性归因于纳米液滴的类似晶体的晶格结构。通过对样品的冷冻断裂表面进行透射电子显微镜观察到了晶格结构。小角中子散射（SANS）显示除了 17nm 半径的球形域之外还存在有序结构。这种远程有序原则上是由于带电纳米液滴之间的静电排斥相互作用。动态光散射（DLS）显示了两种弛豫模式，一种用于晶格的集体运动，另一种用于纳米液滴的平移扩散。纳米乳液的稀释导致从类似晶体的结构到典型胶体溶液的转变。
