Abstract
Everyday experience confirms the tendency of adhesive films to detach from spheroidal regions of rigid substrates — what is a petty frustration when placing a sticky bandage onto a knee is a more serious matter in the coating and painting industries. Irrespective of their resistance to bending, a key driver of such phenomena is Gauss’ Theorema Egregium, which implies that naturally flat sheets cannot conform to doubly-curved surfaces without developing a strain whose magnitude grows sharply with the curved area. Previous attempts to characterize the onset of curvature-induced delamination, and the complex patterns it gives rise to, assumed a dewetting-like mechanism in which the propensity of two materials to form contact through interfacial energy is modified by an elastic energy penalty. We show that this approach may characterize moderately bendable sheets, but fails qualitatively to describe the
curvature-induced delamination of ultrathin films, whose mechanics is governed by their propensity to buckle, and delaminate partially, under minute levels of compression. Combining mechanical and geometrical considerations, we introduce a minimal model for curvature-induced delamination accounting for the two buckling motifs that underlie partial delamination: shallow “rucks” and localized “folds”. We predict nontrivial scaling rules for the onset of curvatureinduced delamination and various features of the emerging patterns,
which compare well with experiments. Beyond gaining control on the use of ultrathin adhesives in cutting edge technologies such as stretchable electronics, our analysis is a significant step towards quantifying the multiscale morphology that emerges upon imposing geomet
curvature-induced delamination of ultrathin films, whose mechanics is governed by their propensity to buckle, and delaminate partially, under minute levels of compression. Combining mechanical and geometrical considerations, we introduce a minimal model for curvature-induced delamination accounting for the two buckling motifs that underlie partial delamination: shallow “rucks” and localized “folds”. We predict nontrivial scaling rules for the onset of curvatureinduced delamination and various features of the emerging patterns,
which compare well with experiments. Beyond gaining control on the use of ultrathin adhesives in cutting edge technologies such as stretchable electronics, our analysis is a significant step towards quantifying the multiscale morphology that emerges upon imposing geomet
Original language | English |
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Article number | e2212290120 |
Journal | Proceedings of the National Academy of Sciences |
Volume | 120 |
Issue number | 12 |
DOIs | |
Publication status | Published - 17 Mar 2023 |
Keywords
- Geometric incompatibility
- Adhesion
- Thin sheets