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Optimization of Ring-Opening Metathesis Polymerization (ROMP) under Physiologically Relevant Conditions
Derek C Church1, Lauren Takiguchi1, Jonathan K Pokorski1
1Department of NanoEngineering, Jacobs School of Engineering, University of California San Diego, La Jolla, CA 92093, USA.
Polymer Chemistry
|April 2, 2021
Summary
This study optimizes ring opening metathesis polymerization (ROMP) for neutral pH aqueous conditions. Optimized conditions enable efficient polymerization of water-soluble monomers and nanostructure formation.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Materials Science
Background:
- Ring opening metathesis polymerization (ROMP) is a versatile living polymerization technique, typically performed in organic solvents.
- Conducting ROMP in aqueous media under neutral pH is challenging, often requiring co-solvents or acidic conditions.
- Developing neutral pH aqueous ROMP is crucial for applications involving acid-sensitive functional groups and biological settings.
Purpose of the Study:
- To optimize ring opening metathesis polymerization (ROMP) for efficient and controlled polymerization in neutral pH aqueous environments.
- To investigate the effects of solution conditions, such as chloride concentration and pH, on ROMP.
- To demonstrate the utility of optimized aqueous ROMP for polymerizing diverse water-soluble monomers and creating nanostructures.
Main Methods:
- Systematic optimization of ROMP conditions in aqueous solutions, focusing on pH and chloride concentration.
- Utilizing a broad scope of water-soluble monomers for polymerization studies.
- Employing ring opening metathesis polymerization induced self-assembly (ROMPISA) to create nanostructures.
Main Results:
- Identified that excess chloride and subtle pH shifts near physiological conditions significantly impact molecular weight control, polymerization rate, and monomer conversion.
- Successfully polymerized a wide range of water-soluble monomers under optimized neutral pH aqueous conditions.
- Demonstrated the production of nanostructures via ROMPISA in neutral pH aqueous media.
Conclusions:
- Achieved efficient and controlled ROMP in neutral pH aqueous solutions, overcoming previous limitations.
- The findings enable the use of ROMP with acid-sensitive functional groups and in biological applications.
- The developed methodology facilitates the synthesis of functional polymers and nanostructures in environmentally benign aqueous conditions.
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