Application-Related Consideration of the Thermal Stability of [mTBDH][OAc] Compared to Amidine-Based Ionic Liquids in the Presence of Various Amounts of Water

Abstract

The hydrolysis kinetics of 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enium acetate [mTBDH][OAc] was investigated in a comprehensive study by the utilization of the well-known Schlenk technique to achieve a better understanding of its stability for dry-jet wet spinning applications (e.g., Ioncell) and due to the course of operation for recovery methods like fractional distillation. Decomposition behavior as a function of temperature, time, acid–base stoichiometry, and water content was extensively analyzed and characterized by nuclear magnetic resonance spectroscopy (NMR), capillary electrophoresis (CE), and thermogravimetric analysis (TGA). Furthermore, kinetic models were formulated for the prediction of the stability and the results were compared with the closely related amidine-based analogues 1,5-diazabicyclo[4.3.0]non-5-enium acetate [DBNH][OAc] and 1,8-diazabicyclo[5.4.0]undec-7-enium acetate [DBUH][OAc].