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Thermosets Based on Covalent Bond Exchange: Mechanisms, Properties, and Reprocessing
Xiaojuan Shi1,2, Daotong Zhuang1
1Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, China.
Polymers
|June 12, 2026
Summary
Dynamic covalent chemistry enables sustainable thermosets with self-healing and recycling capabilities. This review explores dynamic thermosets, linking molecular mechanisms to improved material performance and processing.
Area of Science:
- Materials Science
- Polymer Chemistry
- Sustainable Engineering
Background:
- Thermosets offer excellent mechanical, thermal, and chemical properties essential for engineering applications.
- The rigid, permanently crosslinked structure of conventional thermosets hinders repair, reshaping, and recycling efforts.
- Dynamic covalent chemistry presents a promising strategy to overcome these limitations by introducing reversible bond exchange.
Purpose of the Study:
- To review and analyze various dynamic thermosets developed using different reversible bond exchange mechanisms.
- To correlate molecular-level exchange processes with macroscopic properties and network topology evolution.
- To identify key design principles for creating dynamic thermosets with enhanced sustainability and processing compatibility.
Main Methods:
- Examination of representative dynamic thermoset systems based on transesterification, Diels-Alder reactions, imine exchange, disulfide metathesis, boronic ester exchange, and siloxane equilibration.
- Analysis of the relationship between molecular exchange mechanisms and network dynamics.
- Correlation of molecular behavior with macroscopic performance, including self-healing, reprocessing, welding, and recycling.
Main Results:
- Demonstration of diverse dynamic covalent chemistries enabling reversible crosslinking in thermoset networks.
- Evidence of self-healing, reprocessing, welding, and closed-loop recycling capabilities in these dynamic thermosets.
- Understanding of how molecular exchange influences network topology and material properties.
Conclusions:
- Dynamic covalent chemistry is a viable approach to designing advanced thermosets with improved sustainability.
- The review provides insights into structure-property relationships for tailored material design.
- Future development of dynamic thermosets can lead to more environmentally friendly and versatile materials.
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