Related Experiment Video
Updated: May 21, 2026
07:02
The Preparation and Properties of Thermo-reversibly Cross-linked Rubber Via Diels-Alder Chemistry
Published on: August 25, 2016
Dynamic Ethylene Propylene Rubber (EPR) Network via Multi-Arm Boronic Ester Crosslinkers
Tong Zhao1, Tianquan You1, Hongchi Tian2,3
1State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, P. R. China.
Macromolecular Rapid Communications
|May 20, 2026
Summary
This study introduces a new trifunctional boronic ester crosslinking method for ethylene propylene rubber (EPR) elastomers. This approach enhances crosslinking efficiency and mechanical properties, enabling recyclable, high-performance materials.
Area of Science:
- Polymer Chemistry
- Materials Science
- Elastomer Engineering
Background:
- Dynamic crosslinked elastomers offer reprocessability and mechanical strength.
- Saturated polyolefin elastomers like ethylene propylene rubber (EPR) face challenges in dynamic network development due to low reactivity and slow kinetics.
Purpose of the Study:
- To develop a topology-engineered dynamic crosslinked EPR elastomer.
- To enhance crosslinking efficiency and material properties in EPR using a trifunctional crosslinking strategy.
Main Methods:
- Synthesized hydroxyl-functionalized EPR via epoxidation-hydrolysis.
- Formed dynamic networks using a trifunctional boronic ester crosslinker.
- Investigated network properties and reprocessing capabilities.
Main Results:
- Achieved significantly improved crosslinking density and mechanical properties (3.5 MPa tensile strength, 312% elongation at break).
- Observed faster stress relaxation without increased activation energy.
- Demonstrated efficient reprocessing with 75% tensile strength retention.
Conclusions:
- Trifunctional crosslinking effectively overcomes limitations in low-functionality elastomers like EPR.
- This strategy provides a generalizable approach for high-performance, recyclable EPR-based materials.
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