Heat capacity and thermal conductivity of hexagonal pyrolytic boron nitride

We have measured the heat capacity and thermal conductivity of the layered material hexagonal pyrolytic boron nitride from 2 to 10 K by a pulse-heating technique. The thermal conductivity has also been determined by a steady-state technique from 1.5 to 350 K. At low temperatures, the heat capacity has a $T^3$ dependence and the thermal conductivity a $T^{2.4}$ dependence. Crystallite size was found from transmission electron micrographs. The influence of dislocations on the thermal conductivity is discussed.