Observing thermal transitions is a useful way of comparing materials and identifying unknown materials. By examining thermograms, the existence and quantity of impurities or additives can be determined. 

Differential Scanning Calorimetry (DSC) measures the rate of energy absorption or evolution over the initial melt, crystallisation and re-heat melt phase. The heat flow into or from a sample can also be measured while held under isothermal conditions. DSC can be used to characterize a range of materials, including: polymers, fibers, films, thermosets, elastomers, composites, organics, and inorganics.

DSC testing can indicate polymeric material degradation through an observed decrease in an expected melting point.  There is a link between the melting point of a polymer and its molecular weight. This means that excessive thermal exposure could result in a polymer having a lower than expected melting point. Comparing the heat data collected at constant heating rates provides us with an insight into the processing methods and material properties. Smithers commonly utilizes DSC in a variety of standard protocols listed below.

A variety of important material properties can be determined via DSC:

  • Glass Transition (Tg) 
  • Melting Points (Tm)
  • Crystallisation Temperature (Tc)
  • Percent Crystallinities
  • Oxidative Stabilities
  • Heat Capacities

Our laboratories have a DSC testing instruments with a calibrated temperature range of between -80°C and 600°C, and heating rates from 0.01°C to 300°C /min. They utilize the power compensated principle; sample and reference materials are each held in a separate, self-contained furnace with its own heater element. It also has an auto-sampler attached.


Common Standards

BS ISO 11357

Covering: Glass transition temperature (Tg), Temperature and Enthalpy of melting and crystallization, Specific Heat Capacity, Oxidation Induction Time

ASTM D1519

Rubber Chemicals - Determination of Melting Range

ASTM D3418

Transition Temperatures and Enthalpies of Fusion and Crystallization of Polymers by Differential Scanning Calorimetry

ASTM D3895

Oxidative-Induction Time of Polyolefins by Differential Scanning Calorimetry


Enthalpies of Fusion and Crystallization by Differential Scanning Calorimetry

ASTM E1356

Assignment of the Glass Transition Temperatures by Differential Scanning Calorimetry

ASTM E2160

Heat of Reaction of Thermally Reactive Materials by Differential Scanning Calorimetry