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Updated: Jun 21, 2025
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Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
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A Versatile Reversible, Degenerative Chain Transfer Mechanism for the Catalytic Living Ring-Opening Metathesis
Indradip Mandal1, Andreas F M Kilbinger1
1Department of Chemistry, University of Fribourg, CH-1700, Fribourg, Switzerland.
Angewandte Chemie (International Ed. in English)
|July 9, 2024
Summary
A novel degenerative exchange mechanism enables catalytic living ring-opening metathesis polymerization (ROMP). This greener approach synthesizes polymers, block copolymers, and star polymers efficiently using ruthenium catalysts.
Area of Science:
- Polymer Chemistry
- Organometallic Chemistry
Background:
- Most metathesis polymers derived from norbornene feature a vinyl end group.
- These vinyl end groups are prone to degenerative chain-end exchange reactions.
Purpose of the Study:
- To demonstrate a catalytic living ring-opening metathesis polymerization (ROMP) method.
- To utilize a degenerative exchange mechanism for controlled polymer synthesis.
Main Methods:
- Exploiting degenerative exchange of terminal methylene units in vinyl-terminated polymers.
- Employing Grubbs ruthenium complexes as catalysts.
- Utilizing chain transfer agents (CTAs) based on styrene or conjugated dienes for initiation.
Main Results:
- Achieved catalytic living polymerization of ROMP polymers.
- Demonstrated synthesis of linear polymers, block copolymers, and star polymers.
- Showcased the versatility of CTAs for controlled polymer architectures.
Conclusions:
- The reversible exchange mechanism provides a sustainable and cost-effective route for living ROMP polymer synthesis.
- This method offers a greener alternative to traditional ROMP techniques.
- Enables precise control over polymer molecular weight and architecture.
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