This material characterization technique is used to determine the thermal transitions of a polymer (i.e., glass transition temperature, melting temperature, and crystallization temperature). It is also used to determine oxidative induction times (OIT), specific heat capacity, and can be used to measure the thermal conductivity of a material. DSC measures the heat flow of a sample and compares it to the heat flow of a reference sample exposed to the same environment in order to obtain the heat flux of the sample being characterized.
D3418-15, E793-06, E1356-08, D7426-08, D3895-19, E1858-08, E1269-11
This standard provides a method for determining the glass transition temperature (Tg), melting temperature (Tm), crystallization temperature (Tc), and the enthalpies of fusion (ΔHm) and crystallinity (ΔHc) of polymers. The samples are heated and cooled under constant rates and the properties are measured. The effect of processing, field exposure, or life testing may be extracted through analysis.
This standard provides a method for determining the oxidative-induction time of polyolefin resins by DSC. For this test, the sample is first heated in a nitrogen gas environment and is switched to an oxidative environment at a certain temperature (200°C typically). The specimen is held at this temperature until the oxidative reaction is shown on the thermal curve. The oxidative-induction time of a material is the time from when the material is switched to an oxidative environment until an exothermic peak is shown on the heat flow graph. The OIT is useful for determining the stability of a polymer and to determine the effects of processing or life on remaining antioxidant content.
This standard provides a method to determine the specific heat capacity of a material using DSC. This is done by evaluating the difference in heat flow of an empty pan, a pan with synthetic sapphire and a pan with the sample to calculate the calorimetric sensitivity of the DSC. This value is then used to find the specific heat capacity.