Progress in experimental techniques for dynamic calorimetry

Abstract

The dynamic heat capacity of a substance is a fundamental quantity related to the dynamics of the material and its measurement provides invaluable information on the system dynamics. We developed dynamic calorimeters based on the temperature modulation method and the adiabatic method. These dynamic calorimetric techniques were applied to the study of slow relaxation of a supercooled liquid [Ca(NO3)(2)](0.4)(KNO3)(0.6) near the glass transition. After defining dynamic heat capacity from the linear response theory, we describe theoretical as well as technical aspects of modulation calorimeters and adiabatic calorimeters developed in this laboratory in detail. Based on the dynamic heat capacity data of calcium-potassium nitrate obtained with these calorimeters, merits and demerits of the various methods are pointed out. Future prospects are given. (C) 1997 Elsevier Science B.V.