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Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer used in numerous industrial applications. It is often referred to by its trademark name, Teflon. Thermal characterization of a PTFE material was carried out using various thermal analysis and thermophysical properties test techniques. The transformation energetics and specific heat were measured employing differential scanning calorimetry. The thermal expansion and the density changes were determined employing pushrod dilatometry. The viscoelastic properties (storage and loss modulus) were analyzed using dynamic mechanical analysis. The thermal diffusivity was measured using the laser flash technique. Combining thermal diffusivity data with specific heat and density allows calculation of the thermal conductivity of the polymer. Measurements were carried out from −125 • C up to 150 • C. Additionally, measurements of the mechanical properties were carried out down to −170 • C. The specific heat tests were conducted into the fully molten regions up to 370 • C.

Characterization of liquids, pastes, and melts is nowadays becoming increasingly important for industrial applications. The thermal conductivity of a heat-transfer paste is, for example, one of the crucial parameters for the application of the material, and characterization of polymers in the liquid range is important for the analysis and optimization of the production processes. A new container system has been developed allowing flash measurements to be carried out on liquids, pastes, and molten polymers. Technical details of the container and the data on processing techniques are presented. Reliability tests (on water) have also been carried out and the results are compared with literature values. Various application examples for liquids, pastes, and polymers, through the melt stage are reported.

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