β Scribed by Dirk Henkensmeier; Hyoung-Juhn Kim; Hye-Jin Lee; Dong Hoon Lee; In-Hwan Oh; Seong-Ahn Hong; Suk-Woo Nam; Tae-Hoon Lim
No coin nor oath required. For personal study only.
A series of methyl, benzyl, and mixed polybenzimidazolium halides was synthesised and characterised by NMR spectroscopy. Membranes were formed and ion exchanged with hydroxides. These membranes are of interest for use in potentially platinumβfree anionic exchange membrane fuel cells. Crosslinked membranes were obtained by the addition of Ξ±,Ξ±β²βdibromoβpβxylene to the casting solution. The ion conductivity of membranes was determined by impedance spectroscopy. A hydroxide conductivity of 29 mSβΒ·βcm^β1^ at 26βΒ°C and 58 mSβΒ·βcm^β1^ at 60βΒ°C was obtained. The thermal and hydrolytic stability was investigated and a pathway for hydrolytic degradation proposed. Hydroxide ions react at the 2 position, the intermediate carbinol opens to the amineβamide, and further degrades under chain scission to diamine and carboxylic acid.
magnified image
π SIMILAR VOLUMES
## Alastract4omposite polymeric electrolytes form a new group of solid ionic conductors. Several desirable properties make them suitable for application in various electrochemical devices working over a wide temperature range. In this paper some recent developments in the field of composite polyme
Mixtures of anhydrous lithium iodide and lithium hydroxide monohydrate exhibit conductivity transitions in the region of 170 "C and 100 "C. At the lower temperature transition, increases of two to three orders of magnitude are observed in mixtures containing as little as l/80 by weight of LiOH-HzO.