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Fixing Pillar[5]Arene-Based Rotaxanes Into Epoxy Networks to Produce Toughened Epoxy Resins
Tan-Hao Shi1, Xin Geng1, De-Hui Tuo1,2
1Department of Chemical Science and Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Angewandte Chemie (International Ed. in English)
|July 2, 2026
Summary
This study introduces a simple method to enhance epoxy thermosets using pillar[5]arene. This approach combines mechanical interlocking and covalent bonding for improved material properties.
Area of Science:
- Materials Science
- Polymer Chemistry
- Supramolecular Chemistry
Background:
- Mechanical interlocking enhances epoxy thermoset performance but often requires complex synthesis.
- Existing methods for mechanical interlocking in polymers are typically intricate.
Purpose of the Study:
- To develop a simple strategy for enhancing epoxy thermosets using a dual-functional macrocycle.
- To create poly(pseudo)rotaxanes and integrate them into epoxy networks for improved mechanical properties.
Main Methods:
- Utilized a commercially available hydroxylated pillar[5]arene as both a host and cross-linking unit.
- Formed poly(pseudo)rotaxanes by threading polymer chains through pillar[5]arene macrocycles.
- Achieved in situ curing to fix pillar[5]arene into epoxy networks via mechanical and covalent bonding.
Main Results:
- The resulting epoxy networks demonstrated a balanced combination of tensile strength (29.7 MPa) and toughness (21.6 MJ·m⁻³).
- Mechanical properties were tunable by adjusting pillar[5]arene content and epoxy precursor lengths.
- Successfully combined supramolecular threading with covalent network formation using a single macrocycle.
Conclusions:
- This work presents a convenient and practical route to regulate epoxy network properties.
- The dual-functionality of pillar[5]arene simplifies the process of creating mechanically enhanced thermosets.
- The developed method offers a new approach for designing advanced polymer materials.
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