Self-healing soft electronic and robotic devices can, like human skin, recover autonomously from damage. While current devices use a single type of dynamic polymer for all functional layers to ensure strong interlayer adhesion, this approach requires manual layer alignment. In this study, we used two dynamic polymers, which have immiscible backbones but identical dynamic bonds, to maintain interlayer adhesion while enabling autonomous realignment during healing. These dynamic polymers exhibit a weakly interpenetrating and adhesive interface, whose width is tunable. When multilayered polymer films are misaligned after damage, these structures autonomously realign during healing to minimize interfacial free energy. We fabricated devices with conductive, dielectric, and magnetic particles that functionally heal after damage, enabling thin-film pressure sensors, magnetically assembled soft robots, and underwater circuit assembly.
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Adhesion directed capillary origami
Capillary origami takes advantage of the surface forces of a liquid drop to assemble thin film structures. After a structure is assembled, the drop then evaporates away. The transient nature of the liquid drop means that the creation of dry and stable structures is impossible. Work presented in this paper shows that adhesion is, in fact, a key tool that enables the creation of stable, complex, capillary assembled origami structures, rather than a problem to be avoided. Here, polydimethylsiloxane thin films were used in several simple experiments designed to identify the balance between substrate–film adhesion and film–film adhesion in the context of capillary assembly. We then demonstrate how directional adhesion can be used to direct film peeling in order to create non-trivial patterned folds after a fluid drop is deposited. A minimal complex structure, a “double-fold” was created to demonstrate how adhesion uniquely facilitates multiple-step capillary assembly. Finally, a familiar “origami airplane” was created with these methods, demonstrating that adhesion aided capillary origami can be used to assemble complex, functional structures.
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- Award ID(s):
- 2011681
- PAR ID:
- 10358322
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 17
- Issue:
- 40
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 9170 to 9180
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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