Optimization of Flynn and Levin measurements of polymer thermal conductivity

In this article procedures to measure specifically thermal conductivity of polymers by means of traditional differential scanning calorimetry (DSC) are discussed and an improved procedure minimizing the effect of contact resistances variability has been conceived. A pure substance, namely indium, for which the fusion temperature is known, is added to the polymer sample and used as internal reference in a unique DSC pan. Conductivity is then obtained by measuring the rate of the heat flow through the solid polymer sample during the solid–liquid transition of indium. The present procedure gives uncertainties lower than those expected for thermal conductivity estimations by previous DSC methods, does not require thermal conductivity reference materials nor specimens of various thickness and may be performed routinely with an automatic sample changing device.