초록 |
Colloidal particles are irreversibly attached to fluid-fluid interfaces. Such adsorption decrease the interfacial tension, consequently stabilizing the interface. Therefore, solid particles can be good alternatives to molecular surfactants that are expensive and environment-unfriendly. The behaviors of interface-trapped particles are governed by electrostatics and capillarities. The electrostatic interactions lead to repulsions between the particles, whereas the capillary interactions cause attractions to minimize the surface free energy. Since the relative strength between these two interactions determines the colloidal microstructures and their rheological properties, it is important to quantitatively investigate the interaction forces. In the context of understanding the effect of particle size on the interactions, we fabricate polystyrene particles with controlled size distributions, and measure the interactions between the interface-trapped particles with different dimensions. |