Heterogeneous structure of amorphous polycarbonate as determined by low‐temperature thermal conductivity measurements

Abstract The thermal condcutivity and specific heat of amorphous, non‐oriented polycarbonate were measured in the temperature range between 2 and 80 K. The temperature dependence of the thermal conductivity below 20 K indicates the presence of heterogeneities. The specific surface of these heterogeneities is estimated from the phonon mean free path length. The heterogeneous structure is preserved when the material is heated above the glass transition temperature.