Nonomura Yoshimune, Komura Shigeyuki, Tsujii Kaoru
Tokyo Research Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida-ku, Tokyo 131-8501, Japan.
Langmuir. 2005 Oct 11;21(21):9409-11. doi: 10.1021/la051816m.
Interfaces adsorbing solid particles have recently attracted great attentions in the field of materials science, because they are useful as templates of well-ordered particle arrays or of microstructured hollow spheres. The solid particles are adsorbed at the interfaces and form self-assembled structures when the particles have suitable wettability to both fluids. Here, we show theoretically how the microstructure on the particle surface affects their adsorption properties. The physical properties of the interface adsorbing a particle will be described with consideration for surface area magnification due to the microstructure. The microstructure on the surface changes drastically the wettability and the equilibrium position of the adsorbed particle and prevents the particle from adsorption at the interface. The range of the interfacial tensions at which the particle is adsorbed becomes narrower with the increase of the magnification. On the other hand, the particle which is partially covered with the microstructured surface is adsorbed firmly at the interface in an oriented state. We should consider not only the interfacial tensions but also the surface structure to control the adsorption behavior of the particle.
吸附固体颗粒的界面最近在材料科学领域引起了极大关注，因为它们可用作有序颗粒阵列或微结构空心球的模板。当颗粒对两种流体都具有合适的润湿性时，固体颗粒会吸附在界面处并形成自组装结构。在此，我们从理论上展示了颗粒表面的微观结构如何影响其吸附特性。将考虑由于微观结构导致的表面积放大来描述吸附颗粒的界面的物理性质。表面的微观结构极大地改变了被吸附颗粒的润湿性和平衡位置，并阻止颗粒在界面处吸附。随着放大倍数的增加，颗粒被吸附时的界面张力范围变窄。另一方面，部分覆盖有微结构表面的颗粒以定向状态牢固地吸附在界面处。为了控制颗粒的吸附行为，我们不仅应考虑界面张力，还应考虑表面结构。
