Physique et Mécanique des Milieux Hétérogènes, UMR 7636 du CNRS, PSL Research University, ESPCI, 75005 Paris, France.
Department of Mechanical Engineering, The University of Tokyo, Tokyo 113-8656, Japan.
J Chem Phys. 2023 May 28;158(20). doi: 10.1063/5.0150082.
The spectacular nature of non-wetting drops mainly arises from their extreme mobility, and quick-silver, for instance, was named after this property. There are two ways to make water non-wetting, and they both rely on texture: either we can roughen a hydrophobic solid, which makes drops looking like pearls, or we can texture the liquid with a hydrophobic powder that "isolates" the resulting marble from its substrate. We observe, here, races between pearls and marbles, and report two effects: (1) the static adhesion of the two objects is different in nature, which we interpret as a consequence of the way they meet their substrates; (2) when they move, pearls are generally quicker than marbles, which might arise from the dissimilarity of the liquid/air interface between these two kinds of globules.
不浸润液滴的惊人特性主要源于其极高的流动性,例如,水银就是根据这一特性命名的。有两种使水不浸润的方法,都依赖于纹理:我们要么使疏水固体粗糙化,使液滴看起来像珍珠,要么用疏水粉末对液体进行纹理处理,从而将形成的大理石与基底隔离。在这里,我们观察到珍珠和大理石之间的竞争,并报告了两个效果:(1)两种物体的静态粘附力在性质上是不同的,我们将其解释为它们与基底接触的方式的结果;(2)当它们移动时,珍珠通常比大理石移动得更快,这可能是由于这两种液滴的液体/空气界面不同所致。