The effect of hard segment content on ionic conductivity of poly(ether urethane)-based solid polymer electrolytes

To investigate the effect of hard segment content on ionic conductivities of poly(ether urethane) (PEU)-based solid polymer electrolytes (SPEs), PEUs containing 20, 40, 60, 80, and 100 wt.% of hard segment content were synthesized. Also we introduced polymer-in-salt system with ion-hopping mechanism contrary to traditional salt-in-polymer system with segmental motion mechanism and investigated the effect of hard segment of PEU on ionic conductivities by A.C. impedance, FT-IR, DSC, and SEM. And it could be known that hydrogen bonding of urethane group influenced the ionic conductivities of PEU-based SPE. PEU-based SPE containing 70 wt.% of salt and 20 wt.% of hard segment showed the highest ionic conductivity of 2.95 × 10⁻⁵ S/cm at room temperature.