Dynamic and Static Mechanical Properties of Crosslinked Polymer Matrices: Multiscale Simulations and Experiments

Area of Science:

• Materials Science
• Computational Chemistry
• Polymer Science

Background:

• Understanding the mechanical properties of crosslinked polymer matrices is crucial for material design.
• Existing methods for predicting these properties often face challenges with complex network structures.

Purpose of the Study:

• To develop and validate a multiscale simulation methodology for predicting the static and dynamic mechanical properties of polymer matrices.
• To apply this methodology to phthalonitrile resin and compare simulation results with experimental data.

Main Methods:

• Utilized multiscale simulations, including atomistic molecular dynamics (MD) and dissipative particle dynamics (DPD), to generate and analyze polymer networks.
• Performed experimental dynamic mechanical analysis (DMA) for validation.

Main Results:

• Simulations showed that Young's and storage moduli increase with conversion due to covalent bond formation and reduced molecular mobility.
• MD and DPD simulation data exhibited good quantitative agreement with experimental DMA measurements below the glass transition temperature.
• Simulation data at elevated temperatures were consistent between MD and DPD.

Conclusions:

• The developed multiscale approach accurately predicts mechanical properties of crosslinked polymer matrices.
• This methodology is applicable to a wide range of polymer matrices, including those with high structural heterogeneity.
• The study provides a reliable computational tool for material scientists and engineers.