Singular dynamics in the failure of soft adhesive contacts. Issue 6 (12th December 2018)

• Record Type: Journal Article
• Authors: Berman, Justin D.; Randeria, Manjari; Style, Robert W.; Xu, Qin; Nichols, James R.; Duncan, Aidan J.; Loewenberg, Michael; Dufresne, Eric R.; Jensen, Katharine E.
• Is Part Of: Soft matter. Volume 15:Issue 6(2019)
• Page Start: 1327
• Page End: 1334
• Publication Date: 2018-12-12
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/c8sm02075b
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : We observe that soft gels recoil with singular dynamics after adhesive detachment, driven by surface stress and slowed by viscous flow through the gel's porous, elastic network. Abstract : We characterize the mechanical recovery of compliant silicone gels following adhesive contact failure. We establish broad, stable adhesive contacts between rigid microspheres and soft gels, then stretch the gels to large deformations by pulling quasi-statically on the contact. Eventually, the adhesive contact begins to fail, and ultimately slides to a final contact point on the bottom of the sphere. Immediately after detachment, the gel recoils quickly with a self-similar surface profile that evolves as a power law in time, suggesting that the adhesive detachment point is singular. The singular dynamics we observe are consistent with a relaxation process driven by surface stress and slowed by viscous flow through the porous, elastic network of the gel. Our results emphasize the importance of accounting for both the liquid and solid phases of gels in understanding their mechanics, especially under extreme deformation.