Stretching a Solid Modifies its Wettability… Or Does it?

Abstract

Surface stress and surface energy are physical quantities characterizing the interface between materials. Although these two quantities are identical for interfaces involving only fluids, due to the Shuttleworth effect this is a priori not the case for interfaces involving solids, since their surface energies can change with deformation. Crystals are known to show this effect, but in amorphous solids, like glasses and elastomers, the existence of this effect is debated. In our work, we have measured and modeled the contact angle of liquid microdroplets placed on stretched amorphous solid films. We have shown that glasses exhibit strain-dependent surface energies. In contrast, our results indicate the absence of a strain-dependence for elastomers.