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Reversible Addition-Fragmentation Chain-Transfer Polymerization in Supercritical CO2: A Review
Friso G Versteeg1, Francesco Picchioni1
1Department of Chemical Engineering - Product Technology, University of Groningen, Nijenborgh 4, Groningen, 9747 AG, The Netherlands.
Macromolecular Rapid Communications
|September 11, 2024
Summary
This review explores using supercritical carbon dioxide (scCO2) for cleaner polymerization. While challenges exist in achieving high molar mass, scCO2 offers potential for sustainable, low molar mass polymer production.
Area of Science:
- Polymer Chemistry
- Green Chemistry
Background:
- Volatile organic solvents (VOCs) in polymerization pose environmental and health risks.
- Increasing regulatory pressure necessitates alternatives to traditional VOCs.
- Supercritical fluids offer a promising avenue for sustainable chemical processes.
Purpose of the Study:
- To review the application of supercritical carbon dioxide (scCO2) in polymerization.
- To focus on reversible addition-fragmentation chain-transfer (RAFT) polymerization in scCO2.
- To assess the feasibility of scCO2 as a greener solvent for polymer synthesis.
Main Methods:
- Exploration of RAFT polymerization mechanisms in scCO2.
- Investigation of monomer selection and chain transfer agents (CTAs).
- Analysis of the role of stabilizers in scCO2 polymerization.
Main Results:
- RAFT polymerization in scCO2 is influenced by CTA choice, affecting polymer dispersity and molar mass.
- Stabilizers are critical for controlling polymer properties, except for fluoropolymers.
- Achieving high molar mass polymers in scCO2 is limited by solubility and precipitation.
Conclusions:
- Supercritical CO2 shows potential for sustainable, circular production of low molar mass polymers.
- Further research is needed to overcome limitations for high molar mass polymer synthesis.
- scCO2 polymerization is a step towards greener chemical processes, though not yet fully green.
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