Novel group-transfer polymerization (GTP) of 4-methacryloyloxy-TEMPO for the preparation of poly(4-methacryloyloxy-TEMPO) (PTMA) has been developed. The new PTMA has been tested as an active electrode material in rechargeable organic radical battery (ORB). The advantage of the GTP method is that it affords PTMA containing the theoretical amount of nitroxide groups. Furthermore, cross-linked PTMA was prepared in the presence of small amounts of ethylene glycol dimethacrylate. Cyclic voltammetry of this PTMA showed a single, highly reversible redox couple at a potential of ca. 3.6 V (vs Li/Li+). This potential is similar to the potential of materials (e.g., LiCoO2) used for the positive electrode in lithium-ion batteries. In galvanostatic cycling experiments between 3.0 and 4.0 V in a half-cell setup vs metallic Li as counter and reference electrode a reversible specific charge of ca. 103 Ah kg-1 at current rates up to 1 C was obtained with the cross-linked PTMA. The useable charge capacity is very stable with cycling, showing only a slight decrease after 200 full charge−discharge cycles at 2 C.

A straightforward synthesis of a novel spirobisnitroxide 6 has been developed. Cyclovoltammetry of 6 revealed two distinct reversible oxidation/reduction steps separated by ca. 740 mV indicating the formation of the corresponding oxoammonium cations. Rhodium-catalyzed polymerization of 6 afforded the polyacetylene polymer 7 bearing the pending spirobisnitroxide groups. Additionally, cross-linked 7 was prepared in the presence of 3 mol % of N,N′-diprop-2-ynyl-oxalamide. If oxidation of both nitroxide groups is considered, 7 possesses an unprecedented high theoretical charge capacity of 174 mA h g−1. Evaluation of the cross-linked polymer 7 as a cathode material for an organic radical battery showed very good cycling stability when the potential was kept below the oxidation potential of the five-membered nitroxide subunit of 6. A presumable irreversible degradation of the polymeric backbone of 7 occurred at higher potentials, limiting the experimentally obtained charge capacity to 73 mA h g−1.

The synthesis of new 7‐membered diazepanone alkoxyamines [2,2,7,7‐tetramethyl‐1‐(1‐phenyl‐ethoxy)‐[1,4]diazepan‐5‐one (3) and 2,7‐diethyl‐2,3,7‐trimethyl‐1‐(1‐phenyl‐ethoxy)‐[1,4]diazepan‐5‐one (8)] through the Beckmann rearrangement of piperidin‐4‐one alkoxyamines was developed. Both 3 and 8 were evaluated as initiators and regulators for the nitroxide‐mediated radical polymerization of styrene and n‐butyl acrylate. 8, a sterically highly hindered alkoxyamine readily available as a crystalline solid, allowed the fast and controlled polymerization and preparation of polymers with low polydispersity indices (1.2–1.4) up to a degree of polymerization of about 100. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3332–3341, 2004

New readily available open‐chain alkoxyamines have been synthesized and evaluated as unimolecular initiators for nitroxide‐mediated radical polymerization of styrene and n‐butyl acrylate. The observed moderate control of polymerization is explained by the low thermostability of the parent nitroxide. Copyright © 2004 Society of Chemical Industry