Tests on Polymers: Differential Scanning Calorimetry (DSC)
DSC is a thermal analysis technique that studies how the thermal capacity of a material changes with temperature. The changes taking place during the phases of melting and transition to glassy structure are observed by monitoring the changes in thermal capacity occurring as the material is heated or cooled.
The greatest advantage of DSC instrument is that it easily and rapidly senses transitions in materials. The changes induced by temperature are of importance to many polymers.
A DSC chamber consists of 2 colorimeters. The crucible containing the sample is placed in one, and the crucible containing the reference material is placed in the other. Approximately 2-10 mg of sample is weighed and placed in the sample compartment, and the reference sample prepared in the same way is placed in the reference compartment. In an inert atmosphere (mostly nitrogen), it is heated or cooled at a constant rate to the specified temperature. Polymer samples are generally preheated at a rate of 50°C/min. Then a thermogram is plotted by running a slow heating and cooling program at a rate of 10°C/min. Glass transition, melting and crystallization peaks and even the decomposition curve are assessed on the resulting thermogram.
Testing is performed in accordance with ISO EN 11357-1.