Thermal conductivity, heat capacity, and compressibility of atactic poly(propylene) under high pressure

The thermal conductivity ). and the heat capacity per unit volume of atactic polylpropylene} have been measured in ~.lle temperature range 90 420 K at pressures up to 1.5 G Pa using the transient hot-wire method. The bulk nlOdtlJUS has been measured in the range 200 295 K and up to 0.7 GPa. These data were used to calculate the volume dependence of 2, .~ = - [ (c?).12)/i ~ Iʹ/I "1 ] l, which yielded the Ibllowing wHues [br the glassy state (T<256 K at atmospheric presst, re): 3.80_+0.19 at 200K, 3.74_+0.19 at 225K. 3.90_+0.20 at 250K, 3.77 _+ 0.[9 at 27l K, and 3.73 _+ 0. [9 at 297 K. The resultant value for .~ of tile liquid state was 3.61 _+ 0.15 at 297 K. Values for g wlfich are calculated at 295 K, using theoretical models of ).(T), agree to within 12% with the experimental value Ibr the glassy state.