Thermodynamic properties of poly[bis(trifluoroethoxy) phosphazene] in the range from T→0 TO 620 K

Abstract

Abstract By adiabatic vacuum and dynamic calorimetry, heat capacity for poly[bis(trifluoroethoxy)phosphazene] has been determined over the 6–620 K range. Physical transformations of the polymer on its heating and cooling have been detected and characterized. Smoothed heat capacity C p0(T) and standard thermodynamic functions (H 0(T)-H 0(0), S 0(T) and G 0(T)-H 0(0)) of poly[bis(trifluoroethoxy)phosphazene] have been evaluated for the temperature range from T→0 to 560 K. The standard entropy of formation Δf S 0 at T=298.15 K has been also determined. Fractal dimensions D in the heat capacity function of the multifractal variant of Debye’s theory of heat capacity of solids characterizing the heterodynamics of the tested polymer have been determined.