Netsu Sokutei, 41 (1), p. 17, (2014)



Calorimetric Studies for Standardization and Their Application to Ionic Liquids

Standardization plays important roles in various fields of technology and trade for convenience and mutualrecognition. In this article, author’s activities based on calorimetry and thermal analysis for the standardizationconcerning quality assurance of measurements are briefly described. For the quality assurance including establishmentof metrological traceability, certified reference materials for calibration of analytical instruments were developed byusing adiabatic calorimetry and differential scanning calorimetry (DSC). Cyclohexane was validated as a referencematerial for DSC calibration in a round robin test (RRT) conducted by the working group on standardization in JapanSociety of Calorimetry and Thermal Analysis. The RRT results indicate that appropriate calibration with suitablereference materials reduces significant biases in both temperature and enthalpy. The author also participated in aproject for standardization of ionic liquids conducted by IUPAC. Our measurement capability in calorimetry wasvalidated by agreement of our reported thermodynamic quantities of a reference ionic liquid with those by otherparticipants. Based on the validated capability, we clarified that origin of low melting point of some ionic liquids werelow entropy of crystal from the analysis of alkyl-chain-length dependences of thermodynamic quantities.