FULL PAPER Standardization of PCM Characterization via DSC

Differential Scanning Calorimetry (DSC) is a widely used method for the characterization of phase change materials (PCM). Comparative measurements carried out at different laboratories revealed the need for a standardized methodology to reduce the deviations between these results and to determine representative and reliable PCM characteristics data. Several comparative DSC measurements using different DSC devices have been carried out to develop a standard for the determination of the enthalpy curves for melting and solidification. Laboratory grade Octadecane (Parafol 18-97, Sasol) is used as PCM for these measurements. The first comparison showed large deviations in terms of transition temperature and enthalpy. Thereby, the need for a standardized measurement procedure and a specification of the calibration of DSC devices became apparent. The developed procedure includes: I) the determination of the required heating and cooling rate, II) the calibration of the DSC device under consideration of the determined heating and cooling rate, III) the measurement itself, and IV) the data analysis and representation.