Stress softening of nanoparticle-crosslinked hydrogels described using a physics-based damage model
Xia Liu1, Han Jia1, Junjun Shang1
1Dep. of Engineering Mechanics, Beijing University of Technology, Beijing, 100124, China.
Journal of the Mechanical Behavior of Biomedical Materials
|December 20, 2023
Summary
This study presents a physics-based model for nanoparticle-crosslinked hydrogels, explaining damage mechanisms under cyclic loading. The model accurately describes mechanical behavior, advancing hydrogel applications.
Area of Science:
- Materials Science
- Polymer Science
- Mechanical Engineering
Background:
- Hydrogels possess promising applications but suffer from poor mechanical properties.
- Nanoparticle-crosslinked hydrogels offer enhanced toughness and self-recovery, but their microscale damage mechanisms remain unclear.
Purpose of the Study:
- To establish a physics-based constitutive model for nanoparticle-crosslinked hydrogels under cyclic loading.
- To elucidate the underlying microscale physical mechanisms of deformation-induced and rate-dependent damage.
Main Methods:
- Developed a physics-based constitutive model incorporating network alteration and chain kinetics.
- Modified existing kinetic theory to account for polymer chains winding around nanoparticles.
- Performed cyclic loading tests to validate the model.
Main Results:
- The model successfully explains deformation-induced damage via network alteration.
- Rate-dependent damage is attributed to the kinetics of chain dissociation/association, modified for nanoparticle interactions.
- The model accurately describes Mullins stress softening and recovery during cyclic loading.
Conclusions:
- The proposed constitutive model effectively captures the complex mechanical behavior of nanoparticle-crosslinked hydrogels under cyclic loading.
- This work provides a deeper understanding of hydrogel damage mechanisms, facilitating their use in advanced applications.
