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Updated: Jun 4, 2025
09:34
Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
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Covalent Adaptable Networks from Polyacrylates Based on Oxime-Urethane Bond Exchange Reaction
Yu Sotoyama1, Naoto Iwata1, Seiichi Furumi1
1Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan.
International Journal of Molecular Sciences
|December 17, 2024
Summary
Covalent adaptable networks (CANs) exhibit tunable rheological properties. The study shows that using normal-alkyl acrylates enhances bond exchange reactions, crucial for self-healing and reprocessing in CANs.
Area of Science:
- Polymer Science
- Materials Chemistry
Background:
- Covalent adaptable networks (CANs) utilize dynamic covalent bonds for stimuli-responsive properties.
- These networks offer potential for self-healing and reprocessing applications.
Purpose of the Study:
- To investigate the rheological relaxation properties of polyacrylate films cross-linked with dynamic covalent bonds.
- To evaluate the influence of monomer choice and cross-linker concentration on network behavior.
Main Methods:
- Fabrication of cross-linked polyacrylate films with varying acrylate monomers and diacrylate cross-linkers (oxime-urethane bonds).
- Analysis of rheological relaxation curves using a two-component model (bond exchange and cross-linker melting).
Main Results:
- The bond exchange reaction's contribution to relaxation dominates with normal-alkyl acrylates.
- Relaxation time remained consistent despite adjustments in cross-linker amount.
- Cross-linker miscibility was identified as critical for CAN performance.
Conclusions:
- Normal-alkyl acrylates are key for dominant bond exchange relaxation in CANs.
- Cross-linker miscibility is essential for achieving good self-healing and reprocessability.
- The findings provide insights into designing advanced CAN materials.
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