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Abstract Surface wrinkles have emerged as a promising avenue for the development of smart adhesives with dynamically tunable adhesion, finding applications in diverse fields, such as soft robots and medical devices. Despite intensive studies and great achievements, it is still challenging to model and simulate the tunable adhesion with surface wrinkles due to roughened surface topologies and pre-stress inside the materials. The lack of a mechanistic understanding hinders the rational design of these smart adhesives. Here, we integrate a lattice model for nonlinear deformations of solids and nonlocal interaction potentials for adhesion in the framework of molecular dynamics to explore the roles of surface wrinkles on adhesion behaviors. We validate the proposed model by comparing wrinkles in a neo-Hookean bilayer with benchmarked results and reproducing the analytical solution for cylindrical adhesion. We then systematically study the pull-off force of the wrinkled surface with varied compressive strains and adhesion energies. Our results reveal the competing effect between the adhesion-induced contact and the roughness due to wrinkles on enhancing or weakening the adhesion. Such understanding provides guidance for tailoring material and geometry as well as loading wrinkled surfaces for different applications.
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Mesoscale structure of wrinkle patterns and defect-proliferated liquid crystalline phases
Significance Thin films readily buckle to relax compression, creating wrinkle patterns that may cover large portions of the solid. Predicting the arrangement of wrinkles in general settings is a major challenge that affects our understanding of stresses and deformations in textiles, biological tissues, and synthetic skins. We identify a mesoscale structure that arises from the incompatibility of uniformly spaced wrinkles and a spatially varying director, unraveling an organizing principle with analogs in liquid crystalline and superconducting states of matter.
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- PAR ID:
- 10134153
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 8
- ISSN:
- 0027-8424
- Format(s):
- Medium: X Size: p. 3938-3943
- Size(s):
- p. 3938-3943
- Sponsoring Org:
- National Science Foundation
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