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Updated: Jun 18, 2025
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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
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Efficient Synthesis of Metastable Cyclodextrin-Based Polyrotaxanes with Tunable Threading Ratios.
Bo Qiao1, Qinghong Zeng1, Longyu Li1,2
1College of Polymer Science and Engineering, Sichuan University, Chengdu, 610065, People's Republic of China.
Angewandte Chemie (International Ed. in English)
|July 29, 2024
Summary
This study introduces a streamlined method for synthesizing cyclodextrin-based polyrotaxanes (CD-PRs) using planetary centrifugal mixing and thiol-ene click chemistry. The resulting metastable CD-PRs offer controlled de-threading for advanced material applications.
Area of Science:
- Supramolecular Chemistry
- Polymer Science
- Materials Science
Background:
- Cyclodextrin-based polyrotaxanes (CD-PRs) exhibit dynamic properties valuable for molecular shuttles and drug delivery.
- Conventional CD-PR synthesis is complex, time-consuming, and hinders scalability.
Purpose of the Study:
- To develop a simplified and accelerated method for synthesizing CD-PRs.
- To create metastable CD-PRs with tunable threading ratios and controlled de-threading properties.
Main Methods:
- Utilized planetary centrifugal mixing for rapid polypseudorotaxane (PPR) formation.
- Employed thiol-ene click reaction for efficient end-capping to form PRs.
- Incorporated glutathione (GSH) as a molecular bumper for metastability.
Main Results:
- Planetary centrifugal mixing significantly simplified and accelerated PPR synthesis.
- GSH-capped PRs demonstrated metastability, preventing α-CD ring de-threading at room temperature.
- Heating allowed precise control over the rate of ring de-threading, enabling tunable threading ratios.
Conclusions:
- The developed strategy offers an efficient and scalable approach for CD-PR synthesis.
- Metastable CD-PRs with controlled de-threading open new avenues for advanced functional materials.
- This advancement is crucial for the practical application of CD-PRs in various technological fields.
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