K. Ito, Y. Tominaga, H. Ohno
1997
Citations
0
Influential Citations
48
Citations
Journal
Electrochimica Acta
Abstract
Abstract Benzenesulfonate (Bs) groups were introduced to the terminal of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) oligomers with molecular weight (MW) of 300–6000 to design an ion conductive amorphous matrix. The phase of these PEO-salt hybrids was mainly influenced by the MW of the polyethers. PEO oligomers having benzenesulfonate group(s) with MW less than 600 showed amorphous phase in the bulk in a wide temperature range (−120 ∼ + 150 °C). The ionic conductivity of these amorphous salts was considerably influenced by the glass transition temperature (Tg). The Tg of these PEO-salt hybrids was influenced by the fraction of salt group in the matrix. Among totally amorphous salts, the best ionic conductivity of 2.95 × 10−5 S cm−1, at 50 °C was obtained in the PEO550-BsCs. Though PEO350-BsM was also an amorphous salt, lower ionic conductivity was observed because of higher Tg than that of PEO550-BsM. However, PEO350-BsM was useful as electrolyte in PEO oligomers because of excellent compatibility with the PEO oligomers. The ionic conductivity of PEO350-BsM in PEO300 (MW of 300) was 40 times higher than that of PEO350-BsM in the bulk. Since PEO350-BsM was inherently ion conductive, the ionic conductivity for PEO 350 -BsM PEO 300 was kept high regardless of the salt concentration.