Intercomparison of thermal conductivity and thermal diffusivity methods for plastics

An intercomparison of measurements of the thermal conductivity and thermal diffusivity of two poly(methyl methacrylates) is reported. A wide variety of methods were used: temperature wave analysis, laser flash, transient plane source (Hot Disk^®), transient line-source probe, and heat flux meter methods. Very good agreement of thermal conductivity results and, separately, of thermal diffusivity results was obtained. Similarly, good agreement between thermal conductivity and thermal diffusivity results, when converted using specific heat capacity and density values, was also obtained. Typically, the values were within a range of approximately ±10%. Considering the significant differences between the methods and the requirements on specimen dimensions, the level of agreement between results was considered to be good.