Energy-Renormalization for Achieving Temperature Transferable Coarse-Graining of Polymer Dynamics
Wenjie Xia1,2,3, Jake Song4, Cheol Jeong1
1Materials Science & Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
Macromolecules
|April 19, 2019
Summary
This study introduces a new coarse-grained (CG) modeling method to accurately predict polymer dynamics across various temperatures. The approach corrects for altered thermodynamics in CG models, enabling reliable material property predictions.
Area of Science:
- Soft Matter Physics
- Computational Materials Science
- Polymer Physics
Background:
- Bottom-up prediction of polymer properties using molecular dynamics is challenging.
- Coarse-grained (CG) models accelerate simulations but alter thermodynamics and dynamics.
- Existing CG models lack temperature transferability and chemical specificity for polymer dynamics.
Purpose of the Study:
- To develop a temperature-transferable and chemically specific coarse-grained (CG) method for polymer dynamics.
- To address deviations in activation free energies caused by coarse-graining.
- To enable accurate prediction of polymer dynamics across the entire glass formation range.
Main Methods:
- Proposed a strategy based on Adam-Gibbs (AG) theory for glass formation.
- Renormalized cohesive interaction strength and effective interaction length-scale parameters.
- Corrected activation free energy deviations in coarse-grained polystyrene dynamics.
Main Results:
- The energy-renormalization method accurately predicts atomistic polymer dynamics.
- Predictions cover the Arrhenius, non-Arrhenius, and non-equilibrium glassy regimes.
- Demonstrated accurate modeling of dynamic properties over the entire glass formation range.
Conclusions:
- Developed a practical scheme for temperature-transferable CG models.
- Enables predictive modeling and design of polymeric material properties.
- Overcomes limitations of traditional CG methods for polymer dynamics.
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