Redox Polymer–Based Nano‐Objects via Polymerization‐Induced Self‐Assembly

• Published in: Macromolecular chemistry and physics Vol. 221; no. 1
• Main Authors: Boujioui, Fadoi, Zhuge, Flanco, Gohy, Jean‐François
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.01.2020
• Subjects: Aqueous solutions; Assembly; Chain transfer; Electrons; Ethylene glycol; Hydrophilicity; Microprocessors; nitroxide radicals; Polymerization; polymerization‐induced self‐assembly; Polymers; redox flow batteries
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.201900296

Poly(2,2,6,6‐tetramethylpiperidinyloxy‐4‐yl‐methacrylate) (PTMA) redox polymer–based nano‐objects are synthesized by polymerization‐induced self‐assembly with poly[oligo(ethylene glycol) methyl ether methacrylate] and poly[(4‐methacryloyloxy)‐2,2,6,6‐tetramethylpiperidinium chloride] as hydrophilic macro‐chain transfer agents. These hydrophilic blocks are used in order to stabilize hydrophobic PTMA blocks in aqueous medium. The accordingly obtained spherical nano‐objects are observed via transmission electron microscopy analysis. Cyclic voltammetry measurements indicate that the nature and the length of coronal blocks influence the redox process of the PTMA core blocks. Moreover, these electroactive nano‐objects display low viscosities with a shear‐thinning behavior, making them suitable as cathode‐active materials for aqueous flow‐assisted electrochemical systems. Polymerization‐induced self‐assembly is used to prepare spherical nanoparticles containing a redox poly(2,2,6,6‐tetramethylpiperidinyloxy‐4‐yl‐methacrylate) (PTMA)‐insoluble block. Cyclic voltammetry demonstrates that the nitroxide groups of PTMA can be reversibly oxidized into oxoammonium cations. The obtained solutions show a low viscosity at a 10 wt% polymer concentration with a shear‐thinning behavior, making them ideal candidates for redox flow cells.