Differential scanning calorimetry (DSC) measures the heat flow into or out of a sample relative to an inert reference as both are subjected to a controlled temperature program. Endothermic events such as melting and exothermic events such as crystallization, curing, or oxidation appear as deviations in the heat-flow signal, producing a thermal fingerprint of the material.

DSC can characterize a wide range of physical and chemical behavior, including:

• Glass transition, melting, and crystallization — fingerprinting polymers and detecting blends or contamination
• Percent crystallinity and heat of fusion
• Curing reactions — degree of cure, cure enthalpy, and reaction onset
• Heat capacity
• Oxidative stability — oxidative induction time and temperature (OIT/OOT)
• Decomposition and other thermal events
• Purity, via melting-point depression analysis
• Thermal and processing history

These measurements support material identification, failure analysis, and the characterization of unknown deposits and contaminants.