The natural rubber specific heat capacity dependence on pressure was estimated on thermodynamic grounds on the basis of the values empirically determined from differential scanning calorimetry data, (in the temperature range of 70 to 50 degrees C), and by means of the Tait equation of state (in the pressure range of 0.1240 MPa). It was found that the specific heat capacity decreases with pressure, being the dependency more pronounced at low pressures. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013