Supercritical RROP: Exploring the radical ring-opening polymerisation of 2-methylene-1,3,6-trioxocane in supercritical CO2 as a green solvent

Mehner, Fabian; Hopkins, Bradley; Reynolds-Green, Morgan; Keddie, Daniel J.; Howdle, Steven M.; Gaitzsch, Jens

Abstract

Radical ring opening polymerisation (RROP) of cyclic ketene acetals (CKAs) is an attractive technique to synthesize branched, (bio)degradable polyesters. However, CKAs as monomers of RROP suffer from hydrolysis lability, making aqueous heterogeneous precipitation polymerisations challenging. In order to explore the precipitation polymerisation of 2-methylene-1,3,6-trioxocane (MTC) and avoid the hydrolysis of monomer, kinetic studies in supercritical CO2 (scCO2) were performed. Tuning the reaction pressure and temperature allowed for synthesis in varying viscosity domains. Importantly, we describe the precipitation polymerisation of low Tg PMTC (−65 °C) in scCO2. In contrast to literature, where a particle-driven polymerisation mechanism has been described for high Tg polymers, a slurry-like precipitation polymerisation was observed for PMTC. Depending on the reaction temperature, polymers with either (i) a defined density of branches (DB) and a scattering of molar mass values, or (ii) a scattering of DB values and relatively defined molar mass were prepared.

Citation

Mehner, F., Hopkins, B., Reynolds-Green, M., Keddie, D. J., Howdle, S. M., & Gaitzsch, J. (2024). Supercritical RROP: Exploring the radical ring-opening polymerisation of 2-methylene-1,3,6-trioxocane in supercritical CO2 as a green solvent. Polymer, 309, Article 127373. https://doi.org/10.1016/j.polymer.2024.127373

• Journal Article Type: Article
• Acceptance Date: Jul 6, 2024
• Online Publication Date: Jul 25, 2024
• Publication Date: Sep 12, 2024
• Deposit Date: Jul 26, 2024
• Publicly Available Date: Jul 31, 2024
• Journal: Polymer
• Print ISSN: 0032-3861
• Electronic ISSN: 0032-3861
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 309
• Article Number: 127373
• DOI: https://doi.org/10.1016/j.polymer.2024.127373
• Keywords: RROP; MTC; Branching; scCO2; Polyester; scRROP
• Public URL: https://nottingham-repository.worktribe.com/output/37320406
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0032386124007092?via%3Dihub
• Additional Information: This article is maintained by: Elsevier; Article Title: Supercritical RROP: Exploring the radical ring-opening polymerisation of 2-methylene-1,3,6-trioxocane in supercritical CO2 as a green solvent; Journal Title: Polymer; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.polymer.2024.127373; Content Type: article; Copyright: © 2024 The Authors. Published by Elsevier Ltd.