Differential Scanning Calorimetry (DSC) is a material thermal analysis technique that measures the endothermic and exothermic behaviors of a sample during controlled heating or cooling. Its core principle is to maintain the temperature consistency between the sample and the reference, and to reflect the thermal effects occurring in the material by comparing the energy compensation (or temperature difference) between the two.

Glass transition temperature (Tg)

• Mechanism: The molecular segments of amorphous materials (such as epoxy, EVA, polyurethane) begin to undergo cooperative motion.
• Feature: The baseline exhibits a slope change (step-like, rather than peak-like).

R&D value:

Assess the degree of curing (increase in Tg → increase in framework density)

• Evaluate the heat resistance of materials
• Whether the multiphase system is compatible (with one Tg or two Tgs present) DSC testing tips:
• The third temperature rise scan is typically used to avoid historical effects
• Modulated DSC (MDSC) can separate reversible/irreversible heat flow, making Tg clearer