Characterization of (<i>ENR-50</i>)-Ionic Liquid Based Electrolyte System

Abstract

Ionic liquid based on imidazolium cation; 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMITFSI) has been incorporated with epoxidized natural rubber-50 (ENR-50) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) to obtain electrolyte material. Fourier transform infrared spectroscopy (FTIR) spectra showed evidence of complexation between ENR-50, EMITFSI and LiTFSI. Glass transition temperature, Tg displayed an increasing trend with increase in salt concentration. The incorporation of EMITFSI resulted in an increase in ionic conductivity. The increase in ionic conductivity was attributed to the role of ionic liquid which reduced Tg, thus, facilitated ion conduction in the system. The highest ionic conductivity at room temperature was 5.72 ´ 10-4 S cm-1 for sample containing 20 wt% of EMITFSI and 50 wt% of LiTFSI.