Excluded Volume Study of Potassium Polystyrenesulfonate‐Potassium Chloride Solutions

Intrinsic viscosities [ η ], sedimentation coefficients s, radii of gyration R g and second virial coefficients A 2 , refractive index increments and apparent specific volumes were determined in aqueous solution in theta solvents and over a wide range of concentrations m s of a supporting electrolyte KCl, for five samples of potassium polystyrene sulfonate prepared by sulfonation of narrow molecular weight distribution polystyrenes. Coil expansion coefficients α as well as the Flory coefficient Φ relating [ η ] to coil dimensions were evaluated. Following a theory of Alexandrowicz, α 2 was found to be a linear function of M 1/4 m −1/3 S ; Φ appears to decrease with increase in α. The low values of Φ, characteristic for polyelectrolyte solutions, are consistent with the value determined for the Mandelkern‐Flory parameter β = Φ 1/3 P −1 .