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08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
End capping ring-opening olefin metathesis polymerization polymers with vinyl lactones.
Stefan Hilf1, Robert H Grubbs, Andreas F M Kilbinger
1Institut für Organische Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55099 Mainz, Germany.
Journal of the American Chemical Society
|July 24, 2008
Summary
This study introduces a new method for precisely adding functional groups to the ends of polymers made by ring-opening metathesis polymerization (ROMP). This technique allows for direct formation of functional polymer chain ends without extra steps.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Materials Science
Background:
- Selective functionalization of polymer chain ends is crucial for advanced material properties.
- Ring-opening metathesis polymerization (ROMP) using ruthenium carbene initiators has limitations in precise end-group control.
Purpose of the Study:
- To develop a facile and effective end-capping technique for ROMP.
- To introduce functional groups directly onto polymer chain ends using single-turnover olefin metathesis substrates.
Main Methods:
- Utilized vinylene carbonate and 3H-furanone as functionalization and termination agents.
- Employed ruthenium-initiated ring-opening metathesis polymerization (ROMP).
- Investigated the decomposition of acyl carbenes to ruthenium carbides for end-group formation.
Main Results:
- Achieved direct formation of functional polymer end groups (aldehyde, carboxylic acid) without post-polymerization modification.
- Demonstrated high degrees of chain-end functionality.
- Confirmed results using (1)H NMR spectroscopy, MALDI-ToF mass spectrometry, and end-group derivatization.
Conclusions:
- The developed end-capping technique provides a direct route to functionalized polymers via ROMP.
- This method overcomes previous limitations in selective chain-end functionalization.
- Offers a versatile approach for synthesizing polymers with tailored end groups.
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