Nitroxide Radical Polymer-Solvent Interactions and Solubility Parameter Determination

Redox-active polymers such as macromolecular nitroxide radicals have been studied as electrode materials for organic batteries and electronics. Polymer−solvent interactions are essential to processing and device performance, but macromolecular nitroxide radical−solvent interactions are currently not well described. In this talk, the Hildebrand and Hansen solubility parameters of poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) and oxidized PTMA (PTMA+) will be discussed from both experimental and group contribution methods. From these solubility parameters, the group contribution values for the nitroxide and oxoammonium cation were then calculated. It is shown that this information allows for the prediction of polymer−solvent interactions for other nitroxide-based macromolecular radicals. Finally, the discovered solubility parameters are used to predict PTMA electrode formulations for batteries that outperform controls.