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Updated: May 31, 2026
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Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Fracture in glassy polymers: a molecular modeling perspective
1Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC, V6T 1Z1, Canada.
Summary
Molecular modeling and simulations offer key insights into the physics of polymer deformation and fracture. These methods reproduce macroscopic behaviors and reveal underlying atomistic processes in glassy polymers.
Area of Science:
- Materials Science
- Polymer Physics
- Computational Materials Science
Background:
- Molecular modeling and simulations have significantly advanced the understanding of glassy polymer behavior over the last 25 years.
- Experimental observations of polymer deformation and fracture have been a driving force for computational studies.
Purpose of the Study:
- To review key findings from molecular modeling and simulations concerning the physics of deformation and fracture in glassy polymers.
- To contextualize simulation results with experimentally observed polymer behavior.
Main Methods:
- Utilized both atomistic and coarse-grained polymer models.
- Employed various deformation protocols to study mechanical properties.
- Systematically explored trends in shear yield stress, loading conditions, temperature, and strain rate.
Main Results:
- Simulations successfully reproduce macroscopic plasticity features like stress-strain relations and creep response in polymer glasses.
- Revealed atomistic processes underlying deformation, including shear yielding, creep, physical aging, strain hardening, and crazing.
- Demonstrated the role of polymer entanglements and local plasticity in phenomena like strain hardening and crazing.
Conclusions:
- Molecular simulations provide crucial insights into the physics governing polymer deformation and fracture.
- Simulation results align well with experimental observations, enhancing our understanding of polymer mechanics.
- These computational approaches offer a powerful tool for investigating the origin of fracture toughness in amorphous polymers.
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