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Title: Evaporation-Driven Cellular Patterns in Confined Hyperelastic Hydrogels
When a hyperelastic hydrogel confined between two parallel glass plates begins to dry from a lateral boundary, the volume lost by evaporation is accommodated by an inward displacement of the air-hydrogel interface that induces an elastic deformation of the hydrogel. Once a critical front displacement is reached, we observe intermittent fracture events initiated by a geometric instability resulting in localized bursts at the interface. These bursts relax the stresses and irreversibly form air cavities that lead to cellular networks. We show that the spatial extent of the strain field prior to a burst, influenced by the air-hydrogel interfacial tension and the confinement of the gel, determines the characteristic size of the cavities.  more » « less
Award ID(s):
2011754
PAR ID:
10500448
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review Letters
Volume:
131
Issue:
11
ISSN:
0031-9007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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