Segmental Interaction Energy Controls a Wide Range of Material Behavior.

Area of Science:

• Molecular and Materials Modeling
• Thermodynamics
• Polymer Science

Background:

• Segmental interaction energy (ε) is crucial in molecular and material modeling.
• Its value is typically determined using experimental thermodynamic data (e.g., PVT) and equations of state (EOS).

Purpose of the Study:

• To demonstrate the broad influence of segmental interaction energies (ε) on material behavior.
• To establish a direct correlation between ε and the thermal expansion coefficient.
• To link thermodynamic characterization with predictions of material properties like glass transition and relaxation times.

Main Methods:

• Utilizing experimental data to determine segmental interaction energy (ε).
• Employing equations of state (EOS) for molecular size predictions.
• Analyzing correlations between ε and thermal expansion coefficient.
• Investigating dynamic measurements, specifically Slow Arrhenius Process (SAP) relaxations.

Main Results:

• Segmental interaction energies (ε) significantly impact molecular relaxation, glassification, and polymer miscibility.
• A strong, direct correlation was found between ε and the thermal expansion coefficient.
• Thermodynamic characterization was successfully linked to predictions of glass transition temperature, α-process relaxation times, and SAP activation energies/relaxation times.
• Dynamic measurements of SAP relaxations were shown to effectively characterize segmental interactions.

Conclusions:

• Segmental interaction energy (ε) is a versatile parameter with wide-ranging implications in material science.
• The established correlation provides new avenues for thermodynamic characterization, especially with limited data.
• The study bridges thermodynamic characterization and dynamic predictions, offering insights into phenomena from stress relaxation to polymer miscibility.