The single-probe, direct reading thermal comparator has been used extensively to measure the thermal conductivity of bulk solids, liquids, and gases. With the use of an analytical heat flow model based on the work of Dryden1 and the work of Carslaw and Jeager2, the comparator can also be used to obtain an in-situ measurement of the thermal conductivity of a film while attached to a substrate. The purpose of this paper is to test this model by measuring the thermal conductivities of commercially available polymer films (DuPont Kapton and Teflon). The values obtained with the comparator were found to be 0.24 .02 (W/mK) for the Kapton film and to be 0.22 .03 (W/mK) for the Teflon film. Our results are consistent with the conductivity values issued by DuPont. The systematic uncertainty on our measurements is 45% and is mainly due to an inability to accurately estimate a model parameter called the "heat flow radius". This is the radius of the effective heat flow contact area between the probe tip and the film. The TC-1000 thermal comparator technique is also reviewed in this thesis. An attempt is made to explain in detail both the calibration and operating procedures for the thermal comparator.
Library of Congress Subject Headings
Plastic films--Thermal properties--Measurement; Thin films--Thermal properties--Measurement; Heat--Conduction
Department, Program, or Center
Center for Materials Science and Engineering
Li, Dong Ming, "Measurement of thermal conductivities of polymer films with the TC-1000 thermal comparator" (1990). Thesis. Rochester Institute of Technology. Accessed from
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