THERMAL TRANSPORT IN A GLASSY POLYMER AFTER BEING COMPRESSED AT HIGH-PRESSURE

The thermal conductivity of an amorphous polymer (Scotchcast-8) were m easured in its densified and undensified states. The densified sample was compressed under a pressure of 15 GPa for 2 h at room temperature. The thermal conductivity of this densified sample displays a plateau at temperatures between 30 and 60 K. The magnitude of the thermal cond uctivity at and above the plateau is about three times higher than tha t of uncompressed samples. After the sample sits at room temperature f or several weeks, its specific heat and thermal conductivity indicate that the sample was almost completely relaxed.