M Zare - Department of Mechanic, University of Sistan and Baluchestan, Zahedan, Iran
F Yousefi - Department of Chemistry, Yasouj University, Yasouj, Iran

Polymers are widely used in manufacturing, residential etc. For example polyethylene glycol,abbreviated following ISO standard PEG, is a polyether compound and mostly used polymerwith many application such as medicine. It is difficult to figure out lives that is not affectedby polymers [1,2].In this study, the modified van der Waals equation of state (EOS) is used to model PVTbehavior of polymer melts consisting polyethylene glycol (PEG), poly propylene (PP), poly(1 -butene) (PB1) and polyvinyl methyl ether (PVME) over the entire range of availabletemperature and pressure. The obtained results indicate that the modified van der Waals EOShave a good dealing with experimental data by mean average absolute deviation (AAD) of0.0218, 0.4919, 0.6808, 0.1446, respectively.