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Updated: Sep 21, 2025
09:06
Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
7.4K
Nonlinear Viscoelasticity and Generalized Failure Criterion for Polymer Gels.
Bavand Keshavarz1, Thibaut Divoux2,3, Sébastien Manneville4
1Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
ACS Macro Letters
|June 2, 2022
Summary
This study models protein gels, revealing their nonlinear mechanical behavior and predicting failure points using a new integral constitutive equation. The findings suggest failure in soft gels follows similar principles to hard materials.
Area of Science:
- Materials Science
- Polymer Physics
- Rheology
Background:
- Polymer gels are soft viscoelastic solids with nonlinear mechanical responses.
- These materials often exhibit stiffening before fracture and irreversible failure.
Purpose of the Study:
- To describe the mechanical response of a model protein gel.
- To quantitatively predict gel behavior up to macroscopic failure using a constitutive equation.
Main Methods:
- Developed an integral constitutive equation based on linear and nonlinear viscoelastic properties.
- Coupled computed stress response with Bailey's durability criterion for brittle solids.
Main Results:
- The integral constitutive equation accurately predicted the gel's mechanical response in shear start-up experiments.
- Successfully predicted critical stress (σc) and strain (γc) values at failure.
- Demonstrated excellent agreement between theoretical predictions and experimental data.
Conclusions:
- Failure in soft viscoelastic gels appears to be a Markovian process.
- Bailey's failure criterion is applicable to soft gels, extending its use beyond hard materials like metals and glasses.
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