Thermal diffusivities of commercial transparent polymer films measured using laser induced thermal wave

Abstract

The thermal diffusivities of transparent polymer films were measured using a laser induced thermal wave generated on a carbon substrate. This method easily takes into account the thermal impedance difference between a transparent polymer film and carbon substrate. The root modulation frequency dependence of the phase delay of thermal waves in position with and without a transparent polymer film was investigated. In this paper, we describe the principle of the measurement method and several equations used in the evaluation. Finally, the thermal diffusivities of the transparent polymer films, such as poly(vinylidene fluoride), poly(ethyleneterephthalate), and polyimide, were investigated by this method.