Rheological Behavior of Polyelectrolytes Based on Cellulose and Ionic Liquids Dissolved in 1-Ethyl-3-methyl Imidazolium Acetate

The regioselective derivatization of cellulose with three different ionic liquids via click chemistry is investigated. The novel polyelectrolytes are characterized in detail by elemental analysis, FT-IR-spectroscopy, and 1H and 13C-NMR spectroscopy. In addition, the rheological behavior of the compounds is studied in 1-ethyl-3-methyl imidazolium acetate as the solvent. A Newtonian flow behavior is recorded for all cellulose samples at a concentration of 5 wt%. Due to the modification, the viscosity is reduced by at least one decade compared to unmodified cellulose and can be further controlled by choice of the substituent of the imidazolium ring. Furthermore, the viscosity-temperature dependence is analyzed with the VogelFulcherTammann equation and the Arrhenius plot.