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Updated: Mar 25, 2026
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The Assembly and Application of 'Shear Rings': A Novel Endothelial Model for Orbital, Unidirectional and Periodic Fluid Flow and Shear Stress
Published on: October 31, 2016
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Tube Dynamics Works for Randomly Entangled Rings
1Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
Physical Review Letters
|February 27, 2016
Summary
The tube model accurately predicts polymer dynamics using simulations of ring polymers. This model captures segmental motion from local movements to full equilibration, confirming its microscopic assumptions.
Area of Science:
- Polymer Physics
- Materials Science
- Rheology
Background:
- The tube model is fundamental to understanding polymer rheology.
- Microscopic assumptions of the tube model require validation.
Purpose of the Study:
- To test the microscopic assumptions of the tube model.
- To evaluate the tube model's applicability to ring polymers.
Main Methods:
- Simulating topologically equilibrated ring polymers.
- Analyzing polymer dynamics free from end segment relaxation.
Main Results:
- A closed-form expression from the adapted tube model quantitatively predicts segmental mean squared displacements.
- Predictions cover the full range of time scales, from local motion to complete equilibration.
- A time-independent local friction factor was identified.
Conclusions:
- The tube model's microscopic assumptions are validated for ring polymers.
- The adapted tube model provides accurate predictions for polymer dynamics.
- The findings support the use of the tube model in polymer rheology research.
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