Dilute and concentrated solutions of polystyrene in trans-decalin close to and far from the θ-temperature—1. Velocity sedimentation measurements

Velocity sedimentation measurements on polystyrene in trans-decalin up to 100 kg m^?3 and from 20 to 40°C are reported. k_s increases from 0.036 m³ kg^?1 at θ-conditions (20.8°C) to 0.096 m³ kg^?1. Values calculated from the Pyun-Fixman theory agree within 10%. The Yamakawa theory gives the temperature dependence correctly but underestimates k_s. At θ-conditions, s_o/s vs c[η] shows an upward curvature at c[η] ≈ 1.3; at 40°C the plot is linear over the entire region. Sedimentation in concentrated solutions is discussed in terms of permeability.