TITLE:
Solubility of Supercritical CO2 in Polystyrene during Foam Formation via Statistical Associated Fluid Theory (SAFT) Equation of State
AUTHORS:
Brian A. Ott, G. Caneba
KEYWORDS:
Carbon dioxide, polystyrene, SAFT, polymer foams, supercritical fluid
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.9 No.5,
May
20,
2010
ABSTRACT: The use of supercritical fluids, such as CO2, for polymer foam formation has become popular in the last decade. These physical blowing agents are environmentally responsible, and are able to provide certain processing advantages during foam formation. In order to be able to understand foam formation under relatively high pressures and temperatures, thermodynamic phase
equilibrium analysis is required coupled with a good equation of state.
The Statistical Associated Fluid Theory (SAFT) equation of state (EOS) is studied in detail for
the carbon dioxide/polystyrene system, under supercritical CO2 conditions. The SAFT EOS is found to perform better than the Soave-Redlich-Kwong (SRK) EOS, especially when considering liquid phase compositions and densities. Experimental data from the literature is used to
validate model parameters cited in the literature for polystyrene-CO2 binary systems under supercritical conditions. The analysis is done with the assumption that the vapor phase is pure
CO2 and in equilibrium with the liquid CO2-polystyrene condensed phase.