Probing the Effect of Anion Structure on the Physical Properties of Cationic 1,2,3-Triazolium-Based Poly(ionic liquid)s

To extensively explore the influence of anion structure on the physical properties of poly(ionic liquid) s (PILs) a series of PILs having main-chain 1,2,3-triazolium cations was synthesized via copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) followed by N-alkylation with iodomethane and anion metathesis with different metal salts, that is, Li(CF3SO2)(2)N, Li(CF3CF2SO2)(2)N, K(FSO2)(2)N, K(CF3SO2)N(CN), Ag(CN)(2)N, and sodium 4,5-dicyano-1,2,3-triazolate. To isolate the effect of anion on physical properties of PILs, a common iodide precursor was used to maintain constant the average degree of polymerization (DPn) and chain dispersity. Detailed structure/properties relationship analyses demonstrated a lack of correlation between anion chemical structure, ionic conductivity, and glass transition temperatures. Among synthesized series, the PIL derivative having bis(trifluoromethylsulfonyl) imide counter anion showed the best compromise in performance: low glass transition temperature (T-g=-268 degrees C), high thermal stability (T-onset = 340 degrees C) and superior ionic conductivity (sigma(DC) = 8.5 x 10(-6) S/cm at 30 degrees C), which makes it an interesting candidate for various key modern electrochemical applications. (C) 2016 Wiley Periodicals, Inc.