Empirical determination of the pressure-volume-temperature-entropy equation of state of polyethylene in isothermal, isobaric and isochoric ensembles: IV. The modified intrinsic equation of state for the various ensembles

Abstract

ABSTRACT:The intrinsic equations of state for the isothermal, isobaric, isochoric and isoentropic ensembles based on the pressure-volume-temperature-entropy equations of state, P-V-T-S Eos, of polyethylene (PE) reported in our previous works were modified by taking into account a thermodynamic condition at a zero Kelvin limit, such as the entropy and heat capacity are zero at 0 K. The thermodynamic interrelations between the derivatives in the various ensembles were derived from the intrinsic equation of state in the various ensembles, in which a typical interrelation, (∂CV∂V)T=T(∂2P∂T2)V, was considered. The three dimensional plots (3D plot) indicating the interrelation, such as the 3D( TV,V,(∂CV∂V)T) and the 3D(TV,V,T(∂2P∂T2)V) plots, were determined based on the modified intrinsic equation of state and compared to examine the accuracy of the intrinsic equations of state where CV is the isochoric heat capacity and the subscripts T and V mean the isothermal and isochoric ensembles, respectively.Keywords: Intrinsic equation of stateisothermalisobaricisochoricisoentropicthermodynamic derivativesDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.