Swelling-Induced Interface Crease Instabilities at Hydrogel Bilayers

Two dissimilar hydrogel layers bonded together become unstable when the compressive stresses due to diffusion-driven swelling of the layers reach a critical point and creases form at the interface. Although creasing instabilities observed on surfaces of soft solids subjected to large compressions ar...

Full description

Saved in:
Bibliographic Details
Published in:Journal of elasticity 2021-08, Vol.145 (1-2), p.31-47
Main Authors: Dortdivanlioglu, Berkin, Yilmaz, Nil Ezgi Dincer, Goh, K. B., Zheng, Xiaolin, Linder, Christian
Format: Article
Language:English
Subjects:
Automotive Engineering
Chemical potential
Classical Mechanics
Compressive properties
Creasing
Critical point
Diffusion layers
Elastomers
Hydrogels
Material properties
Physics
Physics and Astronomy
Swelling ratio
Transport phenomena
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Two dissimilar hydrogel layers bonded together become unstable when the compressive stresses due to diffusion-driven swelling of the layers reach a critical point and creases form at the interface. Although creasing instabilities observed on surfaces of soft solids subjected to large compressions are well studied, the transient nature and critical conditions for the emergence of interface creases as a result of swelling behavior of hydrogels remain elusive. Here, we investigate the formation and transient growth of interface creases in bilayer hydrogels through experimental and computational approaches. Equipped with a mixed isogeometric analysis that accounts for large swelling deformations along with dissipative fluid transport phenomena, we show that both the equilibrium and the transient characteristics of interface creases can be tuned by controlling the material properties, in contrast to the reported material-independent behavior of creases in elastomers. The effects of material parameters on the onset and growth of interface creases are quantified in terms of the critical swelling ratio and critical chemical potential, and these values are compared to the critical conditions for the emergence of wrinkling instabilities. In agreement with our experimental observations of swelling bilayer hydrogels, our computational results demonstrate that the formation of creases is energetically more favorable than wrinkle formation at the interface.
ISSN:0374-3535
1573-2681
DOI:10.1007/s10659-020-09810-8