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Dispersion polymerisation in supercritical CO2 using macro-RAFT agents.
Mengmeng Zong1, Kristofer J Thurecht, Steven M Howdle
1School of Chemistry, University of Nottingham, Nottingham, UK NG7 2RD.
Chemical Communications (Cambridge, England)
|November 26, 2008
Summary
Fluorinated macro-RAFT agents stabilize dispersion polymerization in supercritical CO2. This method produces well-defined block copolymer particles with a unique fluorinated halo.
Area of Science:
- Polymer Chemistry
- Materials Science
Background:
- Controlled radical polymerization techniques are crucial for synthesizing advanced polymer architectures.
- Supercritical carbon dioxide (scCO2) offers a green and tunable medium for polymerization reactions.
- Dispersion polymerization in scCO2 presents challenges in particle stabilization and control.
Purpose of the Study:
- To investigate the efficacy of fluorinated macro-RAFT agents as in situ stabilizers in dispersion polymerization.
- To achieve controlled synthesis of block copolymers in supercritical CO2.
- To produce well-defined polymer particles with specific morphologies.
Main Methods:
- Dispersion polymerization of block copolymers in supercritical CO2.
- Utilizing fluorinated macro-RAFT (Reversible Addition-Fragmentation chain Transfer) agents.
- Characterization of resulting polymer particles using various analytical techniques.
Main Results:
- Fluorinated macro-RAFT agents effectively acted as in situ stabilizers.
- Good control over block copolymer formation was achieved.
- Well-defined spherical polymer particles with a distinct fluorinated "halo" were successfully synthesized.
Conclusions:
- Fluorinated macro-RAFT agents are highly effective stabilizers for dispersion polymerization in scCO2.
- This approach enables the controlled synthesis of functional block copolymers.
- The method yields unique, well-defined particles suitable for advanced material applications.
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