Seminar über aktuelle Fragen zur Dynamik komplexer Fluide: Morphology of adhesive creases

When a soft elastic material is compressed beyond a certain critical strain, the free surface turns unstable and forms a crease. This corresponds to a sharp fold of the surface onto itself, leading to intricate morphologies as observed for growing tissues and swelling gels. Self-adhesion within the folded region is known to affect nucleation and hysteresis, but a detailed description has remained elusive. Here we resolve the geometry and mechanics of adhesive creases, combining numerical simulations, analysis and experimental results with specific attention to the singular edge of the self-contact. It turns out that adhesive creases exhibit a universal shape that arises from a balance of elastic and surface energies. From this we derive a scaling theory for the intricate bifurcation scenario, explaining the hysteretic nucleation of adhesive creases.