Historically, Tg has been characterized by DSC (Differential Scanning Calorimetry), which is a thermo-analytical method monitoring the difference in heat flow between the material’s specimen and a reference versus time or temperature. The thermomechanical analysis (TMA) is another method that is used to determine Tg. However, for around twenty years DMA analysis has been recognized as the most relevant method. Moreover, unlike DSC and TMA, DMA is sensitive to the excitation frequency: the higher the excitation frequency, the higher the Tg. The usual test to determine Tg via DMA is to perform a temperature ramp on a polymer applying a small sinusoidal deformation to measure the dynamic moduli E’, E”, and Tan δ. Overall, Tg determination is relatively quick (usually between 1 and 3 hours), non destructive and requires relatively small specimens. Tests are also fast to prepare and easy to perform. In this study, an optimized process to measure Tg is presented. The importance of the parameter choices on the outcome is highlighted. Then, different ways to measure Tg are introduced (Storage Modulus E’, Loss Modulus E’’ and Tan δ).
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