Imidazolium-Based Poly(ionic liquid)/Ionic Liquid Ion-Gels with High Ionic Conductivity Prepared from a Curable Poly(ionic liquid)

Ionic liquid (IL)-based ion-gel membranes were prepared from a curable poly(IL)-based materials platform with the free ILs 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]), bis(fluorosulfonyl) imide ([EMIM][FSI]), 1-butylimidazolium bis(trifluoromethylsulfonyl) imide ([C4IMH][TFSI]), and ethylmethylammonium nitrate [EAN][NO3] and evaluated for their ionic conductivity performance at ambient and elevated temperatures. The resulting cross-linked, free-standing ion-gel membranes were found to have less than 1 wt% water (with the exception of [EAN][NO 3] which contained approximate to 20 wt% water). Increasing free IL content from 50 to 80 wt% produces materials with ionic conductivity values >= 10(-2) S cm(-1) at 25 degrees C and approximate to 10(-1) S cm(-1) at 110 degrees C. Additionally, ion-gels containing 70 wt% of the protic ILs [C4IMH][TFSI] and [EMIM][FSI] display ionic conductivity values of approximate to 10(-3) to 10(-2) S cm(-1) over the temperature range of 25-110 degrees C.