Thermodynamic behavior of copolymer using Ihm-Song-Mason equation of state based on surface tension
F. Yousefi and P. Ourak
A simplified analytical equation of with minimum input information was used to predict the volumetric properties of melting copolymers from density at the room temperature, as scaling constant. The calculation of second Virial coefficients (B2), effective van der Waals co-volume (b) and correction factor (α) are required for judgment about applicability of this model to predict of volumetric properties of melting copolymers. This new correlation has been applied to the Ihm-Song-Mason equation of state to predict the volumetric behavior of melting copolymer such as; Poly (ethylene-copropylene) (PEP), Poly (ethylene-co-vinyl acetate) (PEVA), Poly (ethyleneco-metacrylic acid) (PEMA), Poly (ethylene-co-acrylic acid) (PEAA), Poly (ethylene-co-vinyl alcohol) (PEVOH), Poly (styrene-co-acrylonitrile) (PSAN), Poly (acrylonitrile-co-butadiene) (PANB). A collection of 7693 data points for seven mentioned copolymers in the temperature range of 294.95 to 581.55 K and pressures to 2000 bar was used. The obtained results by modified ISM equation of state had good agreement with the experimental data with absolute average deviations of 1.16%.
Keywords: Equation of state, Copolymer melt, Second virial coefficient