Influence of structure and solubility of chain transfer agents on the RAFT control of dispersion polymerisation in scCO2

Alves Costa Pacheco, Ana; Fernandes Da Silva Filho, Arnaldo; Kortsen, Kristoffer; Hanson-Heine, Magnus; Taresco, Vincenzo; Hirst, Jonathan D.; Lansalot, Muriel; D'Agosto, Franck; Howdle, Steven M.

Abstract

Reversible addition-fragmentation chain transfer (RAFT) dispersion polymerisation of methyl methacrylate (MMA) is performed in supercritical carbon dioxide (scCO2) with 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid (DDMAT) present as chain transfer agent (CTA) and surprisingly shows good control over PMMA molecular weight. Kinetic studies of the polymerisation in scCO2also confirm these data. By contrast, only poor control of MMA polymerisation is obtained in toluene solution, as would be expected for this CTA which is better suited for acrylates. In this regard, we select a range of CTAs and use them to determine the parameters that must be considered for good control in dispersion polymerisation in scCO2. A thorough investigation of the nucleation stage during the dispersion polymerisation reveals an unexpected “in situtwo-stage” mechanism that strongly determines how the CTA works. Finally, using a novel computational solvation model, we identify a correlation between polymerisation control and degree of solubility of the CTAs. All of this ultimately gives rise to a simple, elegant and counterintuitive guideline to select the best CTA for RAFT dispersion polymerisation in scCO2

Citation

Alves Costa Pacheco, A., Fernandes Da Silva Filho, A., Kortsen, K., Hanson-Heine, M., Taresco, V., Hirst, J. D., Lansalot, M., D'Agosto, F., & Howdle, S. M. (2021). Influence of structure and solubility of chain transfer agents on the RAFT control of dispersion polymerisation in scCO2. Chemical Science, 12(3), 1016-1030. https://doi.org/10.1039/d0sc05281g

• Journal Article Type: Article
• Acceptance Date: Nov 17, 2020
• Online Publication Date: Nov 17, 2020
• Publication Date: Jan 21, 2021
• Deposit Date: Nov 17, 2020
• Publicly Available Date: Nov 19, 2020
• Journal: Chemical Science
• Print ISSN: 2041-6520
• Electronic ISSN: 2041-6539
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 3
• Pages: 1016-1030
• DOI: https://doi.org/10.1039/d0sc05281g
• Keywords: General Chemistry
• Public URL: https://nottingham-repository.worktribe.com/output/5050238
• Publisher URL: https://pubs.rsc.org/en/Content/ArticleLanding/2021/SC/D0SC05281G#!divAbstract
• Additional Information: : This document is Similarity Check deposited; : Supplementary Information; : Single-blind; : Received 24 September 2020; Accepted 17 November 2020; Accepted Manuscript published 17 November 2020