Chapter 5 - Calorimetric Properties

Abstract

This chapter deals with the calorimetric properties of polymers. The following properties belong to the calorimetric category: specific and molar heat capacities, latent heats of crystallization, or fusion. The specific heat capacity is the heat that must be added per kg of a substance to raise the temperature by one Kelvin or one degree Celsius. The molar heat capacity is the specific heat multiplied by the molar mass. Reliable values for the molar heat capacity in the solid and the liquid state are available for a limited number of polymers only. This emphasizes the importance of correlations between the chemical and the physical structure of polymers. The latent heat of fusion (crystallization) or the enthalpy difference is an important quantity for the calculation of other thermodynamic functions. Furthermore, knowledge of the latent heat of fusion is necessary for the design of a number of polymer processing apparatuses. Reliable experimental values for latent heat of fusion are available, however, for a limited number of polymers only. Based on this understanding, this chapter demonstrates that both groups of properties can be calculated as additive molar quantities. Finally, it suggests that starting from these properties the molar entropy and enthalpy of polymers can be estimated.