Thermodynamic Properties of 1-Propyl-3-methylimidazolium Glutamic Acid Salt

Molar heat capacities (C(p.m)) of the room-temperature ionic liquid (IL) 1-propyl-3-methylimidazolium glutamic acid salt ([C(3)mim][Glu]) were measured with a high-precision automated adiabatic calorimeter (AC) in the temperature range of T = (85 to 360) K. A glass transition was observed at 239.861 K. The enthalpy and entropy of the glass transition were determined to be 2.87 kJ.mol(-1) and 11.97 J.K(-1) . mol(-1), respectively. Two polynomial equations of molar heat capacity as a function of the temperature were fitted before and after the glass transition. The thermodynamic functions (H(T) H(298.15)) and (S(T) - S(298.15)) were derived from the molar heat capacity data in the temperature range of T = (85 to 360) K with an interval of 5 K