Enhanced viscous adhesion using deformable structure

We investigate the adhesion dynamics of a thin elastic structure in contact with a viscous fluid and retracted at a controlled speed, mimicking natural adhesion mechanisms. During detachment, the viscous fluid confined between the deformable structure and a rigid substrate generates an adhesive force due to a pressure drop within the thin film. We show from dedicated experiments that the structural flexibility introduces a strongly nonlinear mechanical response, which significantly alters both the magnitude and the evolution of the adhesion force with retraction velocity. In contrast to rigid systems, the deformability of the structure enables enhanced and tunable adhesion. To capture this interplay, we develop a theoretical framework that couples elasticity and viscosity, providing new insights into how flexible structures enable adhesion control.