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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Ring-Opening Metathesis Polymerization of Nitrile Substituted cis-Cyclooctenes
Martin F Schneider1, Carola Gantner, Werner Obrecht
1WACKER-Lehrstuhl für Makromolekulare Chemie, Technische Universität München, 85748 Garching b. München, Germany.
Macromolecular Rapid Communications
|May 14, 2011
Summary
New nitrile polymers were synthesized using ring-opening metathesis polymerization. These novel polymers exhibit a regular distribution of structural units, unlike conventional nitrile rubbers.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Materials Science
Background:
- Nitrile-containing polymers, such as nitrile rubbers, are widely used due to their unique properties.
- Commercial nitrile rubbers (butadiene/acrylonitrile copolymers) have randomly distributed double bonds, nitrile groups, and methylene bridges.
- There is a need for polymers with controlled structural arrangements for tailored material properties.
Purpose of the Study:
- To synthesize novel nitrile-containing polymers with a regular distribution of structural entities.
- To investigate the effect of nitrile group content on the polymerization rate.
- To compare the structural characteristics of newly synthesized polymers with commercial nitrile rubbers.
Main Methods:
- Ring-opening metathesis polymerization (ROMP) was employed.
- Monomers used were cis-cyanocyclooct-4-ene and cis-1,2-dicyanocyclooct-5-ene.
- A second-generation Grubbs catalyst, [(H(2) IMes)(PCy(3) )Cl(2) Ru=CHPh], was utilized.
Main Results:
- New nitrile-containing polymers were successfully synthesized.
- Polymerization rates decreased with increasing nitrile moiety content on the cyclooctene ring.
- The synthesized polymers demonstrated a regular distribution of structural entities along the polymer chain.
Conclusions:
- Ring-opening metathesis polymerization provides a route to novel nitrile polymers with controlled structures.
- The study highlights a significant difference in structural regularity compared to commercial nitrile rubbers.
- These findings open avenues for developing advanced nitrile-based materials with predictable properties.
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