Solution properties of poly(styrene-co-sodium styrene sulfonate)

The relative conductivities of solutions of poly(styrene-co-sodium styrene sulfonate) (PSSNa) in N,N-dimethylformamide + water have been measured as functions of temperature and at various concentrations. With the aid of the newly proposed theory related to the effect of solute adsorption on the relative conductivity measurement, the experimental data were analysed, and some interesting parameters describing the interfacial properties were deduced. The concentration of PSSNa data dependence of the reduced electrical conductivities has been fitted to an equation similar to the Vogel–Tammann–Fulcher based on the critical concentration model. The intrinsic electrical conductivity of Vogel σ_V], the critical concentration and the concentration of Vogel C_VFT were calculated. The behaviour of polymers close to interfaces has been studied with the parameter of σ_V]. Two mechanisms of interaction between a polymer solution and a surface are in general distinguished, leading to the formation of adsorbed and grafted layers.