Radiation durability of polymeric materials in solid polymer electrolyzer for fusion tritium plant

Iwai, Yasunori; Hiroki, Akihiro; Yamanishi, Toshihiko; Tamada, Masao

This document presents the radiation durability of various polymeric materials applicable to a solid-polymer-electrolyte (SPE) water electrolyzer in the tritium facility of fusion reactor. In the ITER, an electrolyzer should keep its performance during two years operation in the tritiated water of 9 TBq/kg. The condition corresponds to the irradiation of no less than 530 kGy. In this study, the polymeric materials were irradiated with -rays or with electron beams at various conditions up to 1600 kGy at room temperature or at 343 K. The change in mechanical and functional properties were investigated by stress-strain measurement, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray photoelectron spectra (XPS), and so on. Our selection of polymeric materials for a SPE water electrolyzer used in a radiation environment was Pt + Ir applied Nafion N117 membrane, VITON O-ring seal and polyimide insulator.