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Enhanced B-N coordinated dynamic boronate chemistry for recyclable thermosets with elevated stability
Chaoran Xu1,2, Congze He1, Jin Dong1
1State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, China.
Nature Communications
|May 18, 2026
Summary
This study introduces a new N-iminodiacetic acid (N-IDA) boronate system for creating high-temperature, recyclable thermosets. This advanced polymer solution offers enhanced stability and reprocessability, addressing the environmental impact of non-recyclable waste.
Area of Science:
- Polymer Chemistry
- Materials Science
- Sustainable Chemistry
Background:
- Thermoset polymers are widely used but generate significant non-recyclable waste.
- Current dynamic covalent chemistries for thermosets lack the thermal stability required for high-performance applications.
- Existing boronic ester systems typically operate below 150°C, limiting their practical use.
Purpose of the Study:
- To develop a novel dynamic covalent chemistry system for recyclable thermosets with enhanced thermal stability.
- To overcome the temperature limitations of existing boronic ester chemistries.
- To create sustainable polymer solutions for reducing thermoset waste.
Main Methods:
- Development of a N-iminodiacetic acid (N-IDA) boronate system with a strengthened internal B-N coordination bond.
- Leveraging this chemistry to create radical crosslinkers compatible with commercial monomers and thermoplastics.
- Testing the thermal stability, chemical durability, and dimensional stability of the resulting recyclable thermosets.
- Demonstration in heat-shrinkable crosslinked polyethylene (XLPE) for thermal reprocessability.
Main Results:
- The N-IDA boronate system exhibits a strengthened B-N bond (~1.65 Å), enabling controllable exchange above 150°C.
- The developed recyclable thermosets show exceptional thermal stability and durability in harsh environments (85°C/85% RH).
- The system allows for network integrity at service temperatures (<150°C) and reprocessability above 150°C, as shown in XLPE.
- Successful creation of recyclable thermosets without compromising stability.
Conclusions:
- The enhanced B-N coordination in the N-IDA boronate system extends the operational range of dynamic covalent chemistry to high temperatures.
- This work provides a scalable pathway for producing high-performance, recyclable thermosets.
- The developed materials offer a sustainable alternative to traditional non-recyclable thermosets, reducing environmental impact.
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