The thermal analysis of plastic is key to understanding its properties and ability to function in a range of different scenarios.
Differential scanning calorimetry (DSC) is commonly used to evaluate various properties of polymeric materials. The technique allows researchers to observe thermal transitions such as glass transition and melt point temperatures in addition to oxidation or other chemical reactions.
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.
DSC analysis measures the rate of energy absorption or evolution over the initial melt, crystallization, and re-heat melt phase. The heat flow into or from a sample can also be measured while held under isothermal conditions. DSC testing 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:
Our rubber and plastic testing laboratories have 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.