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Published on: April 22, 2016
Supramolecular Modulation of Controlled Radical Polymerization
Shilong Zhu1, Rong-Lin Zhong1, Ling-Qi Meng1
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun130012, China.
Journal of the American Chemical Society
|July 20, 2026
Summary
This study introduces a supramolecular approach using host-guest chemistry to accelerate aqueous controlled radical polymerization (CRP). The method enhances control over polymer synthesis, enabling rapid production of high-molecular-weight polymers and complex block copolymers.
Area of Science:
- Polymer Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Controlled radical polymerization (CRP) allows precise polymer synthesis but faces challenges in balancing polymerization rate and control.
- Existing CRP methods struggle to achieve rapid polymerization speeds while maintaining high fidelity.
- Aqueous polymerization systems are desirable for environmental and safety reasons but often exhibit slower kinetics.
Purpose of the Study:
- To develop a supramolecular strategy to accelerate aqueous photoiniferter and reversible addition-fragmentation chain transfer (RAFT) polymerizations.
- To enhance the efficiency of chain transfer agents (CTAs) through host-guest complexation.
- To achieve rapid polymerization kinetics without compromising control over molecular weight and architecture.
Main Methods:
- Utilized host-guest complexation between cationic thiocarbonylthio-based agents and cucurbit[7]uril (CB[7]) in aqueous media.
- Employed photoiniferter and RAFT polymerization techniques.
- Conducted spectroscopic and computational analyses to elucidate the mechanism of acceleration and control.
Main Results:
- Encapsulation by CB[7] significantly increased the chain transfer coefficient and photolysis efficiency of the CTA.
- The supramolecular system promoted triplet-state population, lowered fragmentation barriers, and facilitated reversible deactivation.
- Successfully synthesized ultrahigh-molecular-weight polymers (Mn up to 2,190 kg mol⁻¹) and well-defined 20-block copolymers.
- Achieved rapid polymerization rates with excellent control over polymer architecture and end-group fidelity.
Conclusions:
- The developed supramolecular strategy effectively balances polymerization rate and control in aqueous CRP.
- Host-guest complexation offers a powerful tool to enhance CTA performance and accelerate polymerization kinetics.
- This approach provides a promising pathway for efficient synthesis of advanced polymer materials in water.
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