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Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
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Aziridine termination of living anionic polymerization
1Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
Macromolecular Rapid Communications
|February 6, 2014
Summary
Researchers achieved a novel switch from carbanions to aza-anions using N-tosylaziridine in anionic polymerization. This method enables amine group introduction, similar to epoxide termination in polymer synthesis.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
Background:
- Anionic polymerization typically involves carbanions for chain growth.
- Introducing amine functionalities via anionic polymerization requires specific activation strategies.
Purpose of the Study:
- To demonstrate the first carbanionic ring-opening of N-tosylaziridine.
- To synthesize poly(styrene)-tosylaziridines with controlled molecular weights.
- To establish a method for introducing amine groups through anionic polymerization.
Main Methods:
- Addition of N-tosylaziridine to living poly(styryl) chains.
- Characterization using (1)H NMR spectroscopy, DOSY (1)H NMR spectroscopy, and size exclusion chromatography (SEC).
- Tosyl group removal and subsequent functionalization.
Main Results:
- Successful switch from carbanions to aza-anions.
- Synthesis of poly(styrene)-tosylaziridines with narrow molecular weight distributions.
- Demonstration of quantitative transfer to azaanionic species after tosyl group removal.
Conclusions:
- N-tosylaziridine enables a novel aza-anionic ring-opening polymerization.
- This strategy provides an alternative to epoxide termination for introducing amine groups.
- The developed method offers precise control over polymer architecture and functionality.
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