Heat capacity, glass-transition, crystallization, and melting temperatures of 1-ethyl-3-methylimidazolium ethylsulfate ([Emim][EtSO4]) and 1-butyl-3-methylimidazolium methylsulfate ([Bmim][MeSO4]) ionic liquids (ILs) have been determined by differential scanning calorimetry (DSC). Their thermal stabilities have been analyzed by thermogravimetric analysis (TGA). Given the effect of the heating rate over the decomposition temperatures, isothermal TGA experiments are proposed as a more appropriate method to evaluate the thermal stability of the ILs. Inside the working range (-150 deg C to 30 deg C), [Emim][EtSO4] and [Bmim][MeSO4] present a glass-transition temperature of -78.4 deg C and -91.9 deg C, respectively. [Bmim][MeSO4] has a melting temperature of -4.1 deg C. The Cp was determined in a working range (10 deg C to 100 deg C) where its value increases lineally with temperature.
Compounds
#
Formula
Name
1
C8H16N2O4S
1-ethyl-3-methylimidazolium ethyl sulfate
2
C9H18N2O4S
1-butyl-3-methylimidazolium methyl sulfate
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.
Type
Compound-#
Property
Variable
Constraint
Phase
Method
#Points
POMD
1
Triple point temperature, K ; Glass
Glass
Liquid
Air at 1 atmosphere
DTA
1
POMD
1
Molar heat capacity at constant pressure, J/K/mol ; Liquid
Temperature, K; Liquid
Pressure, kPa; Liquid
Liquid
Small sample (50 mg) DSC
10
POMD
2
Triple point temperature, K ; Glass
Glass
Liquid
Air at 1 atmosphere
DTA
1
POMD
2
Normal melting temperature, K ; Crystal
Crystal
Liquid
Air at 1 atmosphere
DTA
1
POMD
2
Molar heat capacity at constant pressure, J/K/mol ; Liquid