In this article, we connect the experimental miscibility of several polymer/supercritical carbon dioxide (scCO(2)) mixtures with their pure component properties, such as free volume and interaction energy. We directly address the experimental observations that suggest free volume-rich polymers and those with weak polymer segment segment interaction energies mix more favorably with scCO(2). By applying our simple locally correlated lattice (LCL) theory to model the pressure volume temperature (PVT) behavior of the pure polymers and supercritical solvent, we obtain characteristic molecular parameters which are then used to predict the key physical properties of interest. We probe the underlying thermodynamic contributions (entropic and enthalpic) to the free energies of mixing and show that our LCL theory can explain the experimental miscibility ranking based solely on our characterization of the pure components.