In this study, an analytical method for the temperature waveform measured by temperature-modulated calorimetry is described, and the measurement results of n-hexatriacontane are given as an example. The boundary conditions between the sample and surroundings are investigated by comparing the temperature waveforms obtained when the shape of the sample was altered. In this measurement, a cylindrical sample cell with a radius of 3.0 mm was used. It was found that when the thickness of the sample exceeded 2.0 mm, a portion of the heat flowing out of the sample did not affect the temperature waveform. The amount of heat that flowed out was difficult to measure directly. By analyzing the temperature waveform, we could identify measurement conditions that can ignore physical quantities difficult to evaluate such as heat flow. In other words, this waveform analysis improves the accuracy of the analysis of physical property values. As another example, we also describe an analytical method of the waveforms measured in the phase transition temperature range. The characteristic waveforms were measured because the value of dynamic specific heat changed significantly in the phase transition temperature range. The characteristic waveforms measured in the temperature range are shown as examples.
Keywords:temperature-modulated calorimetry, temperature waveform, dynamic specific heat, linear response, non-linear response.
Publication Date: 2019-10-15