An Analytical Equation of State Extended to Copolymers

Document Type : Research Paper


Young Researchers and Elite Club, Marvdasht Branch, Islamic Azad University,Marvdasht, Iran Abstract


calculate some thermodynamic properties of molten polymers including specific volume and isothermal compressibility (S.M. Hoseini, Physical Chemistry & Electrochemistry, 2 (2014) 56-65). This work extended that EOS to predict the volumetric properties of some molten ethylene copolymers including ethylene/1-octene, ethylene/1-butene (xethylene equal to 0.8543 and 0.563), ethylene/propene. The ability of the extended EOS was checked by comparing the results with 738 literature data points for the specific volumes over the temperature range from 422.35-505.89 K and pressure range from 0.1 up to 200 MPa. The average absolute deviation (AAD) of the calculated specific volumes from literature data was found to be 1.12%. The isothermal compressibility coefficients, κT have also been predicted using ISM EOS. From 180 data points examined, the AAD of estimated κT was equal to 8.48%. Our calculations on the volumetric and thermodynamic properties of studied copolymers reproduced the literature data with reasonably good accuracy.
 Equation of state, Copolymer melts, Thermodynamic properties


[1] P. Moldenaers, R. Keunings, Theoretical and Applied Rheology: Proceedings of the XIth International Congress on Rheology, Brussels, Belgium, August 17-21, 1992, Elsevier, (2013).
[2] Y. Guerrieri, G.M.N. Costa, K.V. Pontes, M. Embiruçu, A Survey of Equations of State for Polymers, INTECH Open Access Publisher, (2012).
[3] N. Orbey, S.I. Sandler, AIChE journal, 40 (1994) 1203-1209.
[4] T. Sako, A.H. Wu, J.M. Prausnitz, Journal of applied polymer science, 38 (1989) 1839-1858.
[5] C. Zhong, H. Masuoka, Fluid Phase Equilibria, 123 (1996) 59-69.
[6] W.G. Chapman, G. Jackson, K.E. Gubbins, Molecular Physics, 65 (1988) 1057-1079.
[7] Z. AMOOZANDEH, F. YOUSEFI, High Temperatures--High Pressures, 44 (2015).
[8] F. Yousefi, P. Ourak, High Temperatures--High Pressures, 43 (2014).
[9] S.M. Hoseini, Physical Chemistry & Electrochemistry, 2 (2014) 56-65.
[10] G. Ihm, Y. Song, E. Mason, The Journal of chemical physics, 94 (1991) 3839-3848.
[11] F. Yousefi, High Temp High Press, 42 (2013) 211-226.
[12] F. Yousefi, H. Karimi, R. Ghafarian Shirazi, M. Gomar, High Temperature High Pressure, (2013) 42451-42467.
[13] C. Wohlfarth, CRC handbook of thermodynamic data of polymer solutions at elevated pressures, CRC Press, (2005).
[14] J. Dymond, R. Malhotra, International journal of thermophysics, 9 (1988) 941-951.