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Synthesis of Terpolymers at Mild Temperatures Using Dynamic Sulfur Bonds in PolyS-Divinylbenzene
Published on: May 20, 2019
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Glass Transition Temperatures and Thermal Conductivities of Polybutadiene Crosslinked with Randomly Distributed
Tannaz Alamfard1, Tommy Lorenz1, Cornelia Breitkopf1
1Chair of Thermodynamics, Institute of Power Engineering, Faculty of Mechanical Engineering, Technical University Dresden, 01069 Dresden, Germany.
Polymers
|February 10, 2024
Summary
This study investigated how sulfur chain length affects polybutadiene
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Polybutadiene crosslinking influences material properties.
- Sulfur chain length is a key parameter in crosslinking.
- Understanding thermal properties is crucial for material applications.
Purpose of the Study:
- Investigate the impact of sulfur chain length on thermal conductivity and glass transition temperature in polybutadiene.
- Analyze the relationship between crosslinking density, molar mass, and thermal properties.
- Explore temperature-dependent thermal conductivity behavior.
Main Methods:
- Equilibrium molecular dynamic (EMD) simulations.
- Green-Kubo method for thermal conductivity calculation.
- Systematic variation of sulfur chain lengths (S1-S8) and molar mass.
Main Results:
- Thermal conductivity decreases with increasing temperature for all models.
- Increasing sulfur chain length and molar mass enhances thermal conductivity (at constant crosslinking).
- Glass transition temperature and density increase with longer sulfur chains and higher molar mass.
Conclusions:
- Sulfur chain length and molar mass are critical factors controlling thermal conductivity and glass transition temperature in polybutadiene.
- Molecular dynamics simulations provide insights into structure-property relationships.
- Tailoring crosslinking parameters allows for tuning of material thermal performance.
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