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Direct Synthesis of Well-Defined Epoxide-Terminated Telechelic Polymers via an Alcohol-Mediated Self-Switching
Shuo Yan1,2, Shunjie Liu1,2, Zihe Liu1,2
1State Key Laboratory of Polymer Science and Technology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, P. R. China.
Angewandte Chemie (International Ed. in English)
|August 12, 2026
Summary
This study introduces an alcohol-mediated self-switching strategy for synthesizing well-defined telechelic polymers in one step. This method achieves precise control over polymer architecture and end-group functionality, overcoming limitations of traditional methods.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Materials Science
Background:
- One-step synthesis of telechelic polymers is desirable for efficiency but challenging due to competing reactions.
- Conventional methods often result in poor control over chain-end structure and broad molecular weight distribution.
- Achieving well-defined telechelic polymers requires precise control over both propagation and end-group functionalization.
Purpose of the Study:
- To develop a novel strategy for the direct synthesis of well-defined telechelic polymers.
- To achieve controlled polymer architectures and high end-group fidelity in a single reaction system.
- To elucidate the mechanism of alcohol-mediated self-switching in ring-opening alternating copolymerization.
Main Methods:
- Ring-opening alternating copolymerization of epichlorohydrin with cyclic anhydrides.
- Utilizing an alcohol-mediated self-switching strategy to control chain-end reactions.
- Mechanistic studies involving hydrogen-bonding interactions and kinetic analysis.
Main Results:
- Successfully synthesized well-defined epoxide-terminated telechelic polyesters with narrow dispersities (Đ ∼ 1.1).
- Achieved high end-group fidelity (>99%) and controllable linear, three-arm, and four-arm architectures.
- Demonstrated alcohol's role in monomer activation, species stabilization, and facilitating self-switching.
Conclusions:
- The alcohol-mediated self-switching strategy enables efficient one-step synthesis of well-defined telechelic polymers.
- This approach overcomes challenges associated with competing chain propagation and end-group functionalization.
- The findings establish a practical method for synthesizing polymers with controlled architectures and functionalities.
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