2002/11/13 by Alan R. Denton, A. R. Denton, Matthias Schmidt +1 · 1 citation
Chemical Engineering · Chemistry · Engineering · Materials Science · Physics and Astronomy · #Binodal #Chemical physics #Chemistry #Colloid #Composite material #Dispersity #Hard spheres #Material Dynamics and Properties #Materials science #Organic chemistry #Phase (matter) #Phase Equilibria and Thermodynamics #Phase diagram #Physical chemistry #Physics #Polymer #Polymer chemistry #Radius of gyration #Rheology and Fluid Dynamics Studies #Thermodynamics #cond-mat.soft #cond-mat.stat-mech
paper · pdf · doi:10.1088/0953-8984/14/46/312
published as J. Phys.: Condens. Matter 14, 12051-12062 (2002) · 14 pages, 4 figures
openalex publication_date 2002/11/13 · arxiv created 2003/02/28 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We consider a model mixture of hard colloidal spheres and nonadsorbing polymer chains in a theta solvent. The polymer component is modelled as a polydisperse mixture of effective spheres, mutually noninteracting but excluded from the colloids, with radii that are free to adjust to allow for colloid-induced compression. We investigate the bulk fluid demixing behaviour of this model system using a geometry-based density functional theory that includes the polymer size polydispersity and configurational free energy, obtained from the exact radius-of-gyration distribution for an ideal (random-walk) chain. Free energies are computed by minimizing the free energy functional with respect to the polymer size distribution. With increasing colloid concentration and polymer-to-colloid size ratio, colloidal confinement is found to increasingly compress the polymers. Correspondingly, the demixing fluid binodal shifts, compared to the incompressible-polymer binodal, to higher polymer densities on the colloid-rich branch, stabilizing the mixed phase.