Differential Scanning Calorimeter (DSC) has been used widely in polymer and pharmaceutical labs. It is used to study the thermal/physical properties of various material systems, e.g. the glass transition Tg, the melting temperature Tm, melting enthalpy, polymorphism etc. Traditionally there are two kinds of DSC depending on different operation principles. One is called Heat flux DSC which measures the temperature difference between sample side and reference side and then calculates the heat flow to the sample. The other is called power compensation DSC which measures the heat flow to the sample side directly while maintaining the sample temp the same as the reference side temperature. Besides this, there are also some significant differences in design. For example, the heat flux DSC has a single, big furnace which has a long response time as a result. The power compensation DSC has two independent small platinum furnace which is much light with a much short response time. The small furnace also enables very fast heating and cooling rates (up to 500 oC/min) than conventional DSC at 10 oC/min. The fast scanning rate has found many interesting and novel applications in the polymer and pharmaceutical industrial which was otherwise impossible before on conventional DSC.
This paper will highlight some important design features of power compensation DSC. The relationship between instrument design and function will be discussed. The performance improvement will be demonstrated and its impacts on applications will be illustrated as well.
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