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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
The Living ROMP of trans-Cyclooctene
Ron Walker1, Rosemary M Conrad, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125.
Macromolecules
|September 28, 2011
Summary
Ring-opening metathesis polymerization (ROMP) of trans-cyclooctene (tCO) yields narrow-dispersity polycyclooctene (PCO). This PCO can be hydrogenated to linear polyethylene or used in functionalized polymers and block copolymers.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Materials Science
Background:
- Ring-opening metathesis polymerization (ROMP) is a versatile method for polymer synthesis.
- Controlling polymer dispersity and side reactions is crucial for advanced materials.
- Trans-cyclooctene (tCO) is a valuable monomer for ROMP.
Purpose of the Study:
- To investigate the living ROMP of trans-cyclooctene (tCO).
- To achieve narrowly dispersed polycyclooctene (PCO) without high molecular weight contaminants.
- To synthesize functionalized PCO and polyethylene-based block copolymers.
Main Methods:
- Living ROMP of tCO using triphenylphosphine (PPh3) in tetrahydrofuran (THF).
- Hydrogenation of PCO to linear polyethylene.
- Polymerization of functionalized tCO monomers.
- Synthesis of block copolymers via ROMP.
Main Results:
- Narrowly dispersed PCO was successfully synthesized by optimizing ROMP conditions.
- PPh3 additive and THF solvent were critical for suppressing side reactions.
- Hydrogenation yielded linear polyethylene with a melting point of 139 °C.
- Functionalized PCO and polyethylene-containing block copolymers were obtained.
Conclusions:
- The developed ROMP method provides controlled synthesis of PCO.
- This methodology enables the creation of linear polyethylene and advanced block copolymers.
- The study demonstrates a pathway to precisely engineered polymer architectures.
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