VISCOELASTIC BRAKING OF A LIQUID-DROP SPREADING ON RUBBER

The kinetics of spreading of a small liquid drop on a solid is controlled by conversion of capillary potential energy into viscous dissipation within the liquid, when the solid is rigid. However, if the solid is sufficiently soft, a local deformation or ''wetting ridge'', may form near the wetting front and motion of the latter may lead also viscoelastic dissipation. A direct comparison is made between this phenomenon and solid/solid adhesion also involving a viscoelastic solid.