Thermophysical properties of organic liquids and polymers over wide ranges of pressure and temperature
Stanisław L Randzio
Scanning transitiometry and pressure-controlled scanning calorimetry have been used for the determination of thermophysical properties (mainly the isobaric expansivity, ap, and specific heat, Cp) of various organic liquids and polymers. The unique properties of simple liquids such as the single crossing point of ap isotherms and minima on the Cp isotherms obtained by these experimental techniques have been modelled with the use of equations of state. The reproduction of those properties is obtained with equations of state with the repulsive branch of the intermolecular pair potential softer than the van der Waals hard sphere. Also for associated liquids and polymers, the thermophysical properties measured over wide ranges of pressure and temperature can serve as a guide in searching further for better equations of state or in verification of existing ones.