A Methoxyamine-Protecting Group for Organic Radical Battery Materials-An Alternative Approach

Kai-Anders Hansen; Lewis C Chambers; Matthias Eing; Christopher Barner-Kowollik; Kathryn E Fairfull-Smith; James P Blinco

doi:10.1002/cssc.201903529

A Methoxyamine-Protecting Group for Organic Radical Battery Materials-An Alternative Approach

ChemSusChem. 2020 May 8;13(9):2386-2393. doi: 10.1002/cssc.201903529. Epub 2020 Apr 15.

Authors

Kai-Anders Hansen¹, Lewis C Chambers¹, Matthias Eing^{1

2}, Christopher Barner-Kowollik¹, Kathryn E Fairfull-Smith¹, James P Blinco¹

Affiliations

¹ Soft Matter Materials Laboratory, Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD, 4000, Australia.
² Macromolecular Architectures, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT), Engesserstrasse 18, 76131, Karlsruhe, Germany.

PMID: 32202387
DOI: 10.1002/cssc.201903529

Abstract

An alternative synthetic route towards the widely employed electroactive poly(TEMPO methacrylate) (PTMA) via a thermally robust methoxyamine-protecting group is demonstrated herein. Protection of the radical moiety of hydroxy-TEMPO with a methyl functionality and subsequent esterification with methacrylic anhydride allows the high-yielding formation of the novel monomer methyl-TEMPO methacrylate (MTMA). The polymerization of MTMA to poly(MTMA) (PMTMA) is investigated via free radical polymerization and reversible addition-fragmentation chain-transfer polymerization (RAFT), a reversible-deactivation radical polymerization technique. Cleavage of the temperature-stable methoxyamine functionality by oxidative treatment of PMTMA with meta-chloroperbenzoic acid (mCPBA) releases the electroactive PTMA. The redox activity of PTMA was confirmed by cyclic voltammetry in lithium-ion coin cells.

Keywords: cathode; esterification; organic batteries; polymers; radicals.