DSC is the generic term for the following two measurement methods.
Figure 1. Block diagram of Heat Flux DSC
DSC is a commercially available instrument which has two (2) types: Heat Flux Type and Power Compensation Type. Figure 1 shows the block diagram of Heat Flux DSC as an example. Heat Flux DSC comprises the sample and reference holder, the heat resistor, the heat sink, and the heater. Heat of heater is supplied into the sample and the reference through heat sink and heat resistor. Heat flow is proportional to the heat difference of heat sink and holders. Heat sink has the enough heat capacity compared to the sample. In case the sample occurs endothermic or exothermic phenomena such as transition and reaction, this endothermic or exothermic phenomena is compensated by heat sink. Thus the temperature difference between the sample and the reference is kept constant. The difference the amount of heat supplied to the sample and the reference is proportional to the temperature difference of both holders. By calibrating the standard material, the unknown sample quantitative measurement is achievable.
DSC enables the measurements of the transition such as the glass transition, melting, and crystallization. Furthermore, the chemical reaction such as thermal curing, heat history, specific heat capacity, and purity analysis are also measurable. Recently, with the development of the highly-functional polymeric material, these thermal properties analysis needs are increasing dramatically. DTA and DSC detect the temperature differences between the sample and the reference; however, DSC can perform the quantitative measurement of the amount of heat on top.
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