Differential Scanning Calorimetry (DSC)

Principle of Differential Scanning Calorimetry (DSC)

  • Calorimetry is the only way for directly determining the enthalpy associated with the process of interest. It is a major technique for measuring the thermal properties of materials to establish a connection between temperature and certain physical attributes of substances.
  • DSCs are divided into two categories based on their functioning mechanisms:
    • These are the two measurement methods.
    • Heat Flux DSCs
      The temperature of the sample unit, which is made up of a sample and a reference material, is changed according to a set of instructions, and the temperature difference between the reference material & the sample is recorded as a function of temperature.
    • Power Compensation DSC
      The sample and reference pans are placed in separate furnaces heated by separate heaters in a power-compensated DSC type.  The sample and reference are kept at the same temperature, and the difference in thermal power required to keep them there is measured and shown as a function of time or temperature.
Heat Flux DSC
Differential Scanning Calorimetry (DSC)


DSC is a available instrument that has two (2) types:

  1. Heat Flux Type
  2. Power Compensation Type.
  • The sample and reference holder, the heat resistor, the heat sink, and the heater make up the Heat Flux DSC.
  • Heat from the heater is transferred to the sample and reference via a heat sink and a heat resistor.
  • The heat difference between the heat sink and the holders determines the heat flow. In comparison to the sample, the heat sink has sufficient heat capacity.
  • When endothermic or exothermic events, such as transition and reaction, occur in the sample, the heat sink compensates for these endothermic or exothermic phenomena.
  • As a result, Temperature differential between the sample and the reference is maintained at the same level.
  • The temperature differential between both holders is proportional to the difference in the amount of heat given to the sample and the reference.
  • The unknown sample quantitative measurement can be achieved by calibrating the standard material.
  • Measurements of transitions such as the glass transition, melting, and crystallisation are possible with DSC.
  • Chemical reactions such thermal curing, heat history, specific heat capacity, and purity analysis can also be measured. These thermal characteristics analysis requirements have risen considerably in recent years, thanks to the introduction of highly useful polymeric materials.
  • DTA and DSC both detect temperature changes between the sample and the reference, but only DSC can quantify the amount of heat on the surface.

Advantages of DSC analysis:

  • Differential Scanning Calorimetry (DSC) is uded in characterizes thermal phase transitions (i.e. crystallization, melting, Tg) and measuring heat of fusion and heat of crystallization.
  • Evaluation on of specific heat capacity of pure compounds or mixtures
  • Determines purity of relatively pure substances.
  • Evaluation of phase separation of polymer blend, copolymers
  • Characterizes cure process, glass transition temperature of the cured sample and residue cure
  • Performs Oxidation Induction Time (OIT)
  • Modulates DSC to determine weak subtle transitions and to separate overlapping thermal events
  • Assesses thermal stability
  • Prepares kinetic study of chemical reaction or decomposition





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