Phase behavior and Li ion conductivity of styrene-ethylene oxide multiblock copolymer electrolytes

Sarapas, J. M.*; 西条 賢次*; Zhao, Y.; 竹中 幹人*; Tew, G. N.*

Polymers for Advanced Technologies, 27(7), p.946 - 954, 2016/07

https://doi.org/10.1002/pat.3753

A molecular weight series of PS-PEO multiblock copolymers was synthesized by the thiol-norbornene click reaction. These materials were characterized both as neat and lithium -trifluorosulfonimide salt loading samples. The neat samples demonstrated the crystallinity increases with PEO contents. The lithium ion-containing samples had broad scattering peaks, half of which displayed disordered scattering. Fitting of disordered scattering peaks by the random phase approximation, yielded the effective Flory-huggins parameter () and radius of gyration () values that were compared to recent predictive works by Balsara and coworkers. The samples were also analyzed by electrochemical impedance spectroscopy for their potential to conduct lithium ions and those with the volume fraction of PEO larger than 0.5 demonstrated robust conductivity.