an analytical equation of state for molten polymers

an analytical equation of state (eos) developed by ihm-song-mason (ism) has been applied tocalculate some thermophysical properties of molten polymers including poly (1-octene) (po), poly (vinylmethyl ether) (pvme), poly (vinyl chloride) (pvc), and poly (styrene) (ps). three temperature-dependentparameters of the ism eos have been determined based on the alternative scaling constants, dispersiveenergy parameters between segments/monomers (ε) and segment diameter (σ). the ability of the proposedeos has been checked by comparing the results with 547 literature data points for the specific volumes overtemperature from 311-557 k and pressure ranging from 0.1 up to 200 mpa. the average absolute deviation(aad) of the calculated specific volumes from literature data was found to be 0.47%. the isothermalcompressibility coefficients, κt have also been predicted using ism eos. from 188 data points examined,the aad of estimated κt was equal to 7.75%. our calculations on the volumetric and thermodynamicproperties of studied polymers reproduce the literature data with reasonably good accuracy.