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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Broad-spectrum lignin-based adhesives using thiol–silyl ether crosslinkers
Lignin is a renewable feedstock that is abundant and inexpensive but still presents challenges for its valorization. In this work, we converted functionalized lignin into broad-spectrum adhesives using thiol–silyl ether crosslinkers. The curing behavior of adhesives was investigated via rheology of their resin forms. These materials exhibit good adhesion on diverse substrates, including wood, glass, steel, aluminium, carbon fiber, and different plastics, with the most adhesion strength in the range of 1–3 MPa. These adhesives were also explored for applications, ranging from wet conditions to different mechanically responsive materials. The mechanism of adhesion was further examined to understand the bonding process.
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- Award ID(s):
- 1806792
- PAR ID:
- 10519107
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 15
- Issue:
- 17
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 1726 to 1735
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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