Sticky crumpled matter

Roughness tolerant pressure sensitive adhesives made of sticky crumpled sheets

“…4 is hysteretic, indicating an energy loss in the cycle. 39 The rise in forces back to zero does not necessarily follow the same curve shape in every experiment. Curves can have a smooth, well-defined tensile peak (as in Fig.…”

“…We make no analysis of this as the power-law shape is well-established in the literature. 30,34,37,39 More important to this work is that the force increases monotonically to some maximum force obtained at a predetermined plate separation (a fixed displacement). As the motor is reversed and the plates are separated the forces dropped quickly to zero and then typically fall below zero and reach a peak tensile force (a minimum in the force curve).…”

“…A detailed analysis of the effect is discussed in ref. 39 and as the hysteresis is not important to our discussion of roughness tolerance it will not be considered further. Additionally, because of the low pull-off force measured for 10 to 1 and 20 to 1 samples, these cross-link ratio sheets will not be used further in tests of roughness tolerance.…”

“…Rather than creating complicated moulded topographies to mimic biology, we choose to exploit the naturally hierarchical structure created when a thin sheet is subjected to 3-dimensional confinement. [26][27][28][29] The mechanics of a crumpled sheet are now well explored in the literature, [26][27][28][29][30][31][32][33][34][35][36][37][38][39] though considerable theoretical debate about the origins of the structure continues. 30,34,36,38 A recent practical advance has been the establishment of a simple, empirical, scaling rule for describing the compressive load held by a crumpled ball.…”

Crumpled Kirigami

“…Ensembles of measurements show not only different values for the average exponents but different distributions of exponents for the different materials, which differ again when surface adhesion is changed. 10,22,23 It is therefore important to take those material properties into account when examining the effect of structural features inside a crumple.…”