Energy renormalization for temperature transferable coarse-graining of silicone polymer

Area of Science:

• Polymer Physics
• Computational Materials Science
• Chemical Engineering

Background:

• Predicting polymer thermodynamic and mechanical behaviors from molecular dynamics (MD) simulations is vital.
• Atomistically informed coarse-grained (CG) models offer improved scale but struggle with temperature transferability, limiting applications.
• Developing temperature-transferable CG models is a significant challenge in polymer physics.

Purpose of the Study:

• To develop a temperature-transferable coarse-grained (CG) model for polydimethylsiloxane (PDMS) using an energy-renormalization (ER) approach.
• To validate the CG model's accuracy in preserving dynamics, mechanical, and conformational behaviors across temperature regimes.
• To explore the impact of cohesive interaction strength and temperature on polymer dynamics and mechanical response.

Main Methods:

• Utilized an energy-renormalization (ER) approach with temperature-dependent factors to adjust parameters for a CG model of PDMS.
• Compared the developed CG model against all-atomistic (AA) simulations and experimental data from glassy to melt states.
• Systematically investigated the effects of cohesive interaction strength and temperature on polymer dynamics and mechanical properties.

Main Results:

• The ER approach successfully created a temperature-transferable CG model for PDMS, accurately reproducing dynamics, mechanical properties, and conformations.
• The model demonstrated significant computational efficiency improvements over all-atomistic simulations.
• Observed consistent trends regarding cohesive interaction strength and temperature effects on dynamical heterogeneity and mechanical response, applicable to other polymers.

Conclusions:

• The developed energy-renormalization (ER) approach enables the creation of accurate, temperature-transferable coarse-grained (CG) models for polymers with diverse structures.
• Cohesive interaction strength plays a critical role in the CG modeling of polymer dynamics and thermomechanical behavior.
• This work extends the ER methodology for CG model development, facilitating broader applications in polymer physics.