Statistical associating fluid theory (SAFT) is an equation of state that can be used to calculate the phase behavior of mixtures comprised of components that exhibit wide disparities in molecular size, such as solvent-polymer mixtures. In this paper, we model the phase behavior of a PVAC-PTAN block copolymer composed of a CO2-phobic polyvinyl acetate (PVAC) and a CO2-philic poly(1,1,2,2-tetrahydroperfluorooetyl acrylate) (PTAN) in supercritical carbon dioxide (scCO(2)) using SAFT. SAFT is a molecular-based equation that is designed to account for effects of molecular association, chain flexibility, repulsive and dispersion interactions. The group contribution approach of Lora et al. was used to obtain the physical SAFT parameters for PVAC and PTAN polymers. PTAN was modeled as a non-associating polymer while PVAC was modeled with two association sites per molecule. Cloud curves of CO2-PVAC, CO2-PTAN and of the PVAC-b-PTAN-CO2 system were predicted, and good agreement was obtained with the experimental data available. Additionally, critical micellar densities (CMD) appear to be successfully predicted for the PVAC-b-PTAN-CO2 system using a criteria based in the variation of osmotic pressure with surfactant concentration. This was made possible by the ability of SAFT to handle long chain and association interactions.