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Updated: Dec 28, 2025
09:06
Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
7.7K
On the Nature of Epoxy Resin Post-Curing
James C Moller1, Rajiv J Berry2, Heather A Foster3
1Department of Mechanical and Manufacturing Engineering, Miami University, Oxford, OH 45056, USA.
Polymers
|February 23, 2020
Summary
Post-curing thermosets enhances strength and thermal properties through ether crosslinks and dehydration. Molecular dynamics simulations reveal these effects on diglycidyl ether of bisphenol A-diamino diphenyl sulfone systems.
Area of Science:
- Materials Science
- Polymer Chemistry
- Computational Chemistry
Background:
- Post-curing is crucial for optimizing thermoset properties like strength and thermal stability.
- Experimental observations suggest ether crosslinking and backbone dehydration occur during post-curing.
- Understanding these molecular changes is key to predicting thermomechanical behavior.
Purpose of the Study:
- To model and compare the thermomechanical effects of etherification and dehydration in thermosets.
- To investigate how resin length, stoichiometry, and reaction type influence these effects.
- To validate molecular dynamics simulations against experimental post-curing results.
Main Methods:
- Utilized molecular dynamics simulations to represent ether crosslinks and backbone dehydration.
- Examined diglycidyl ether of bisphenol A (DGEBA)-diamino diphenyl sulfone (DDS) systems.
- Varied independent parameters including resin length, stoichiometry, and reaction type (etherification, dehydration).
Main Results:
- Etherification significantly strengthened and induced strain hardening in excess epoxide systems.
- Combined etherification and dehydration most closely replicated experimental post-curing outcomes.
- Dehydration increased stiffness and strength in longer resin molecules via hydroxyl group crosslinking.
- Thermal transitions were detected by analyzing specific volume versus temperature curves.
Conclusions:
- Molecular dynamics simulations effectively capture post-curing phenomena like etherification and dehydration.
- Etherification and dehydration are critical factors influencing the thermomechanical properties of DGEBA-DDS thermosets.
- These simulated molecular changes correlate with experimentally observed improvements in material performance.
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