Concentration Dependence of Radius of Gyration of Sodium Poly(styrenesulfonate) over a Wide Range of Concentration Studied by Small-Angle Neutron Scattering

Abstract

Concentration dependence of radius of gyration (Rg) of sodium poly(styrenesulfonate)s (NaPSS) in aqueous solutions without added salt was studied by small-angle neutron scattering measurements over a wide range of concentration. The Rg values are always higher than those of corresponding nonionic polymer, polystyrene, and the concentration (C) dependence of Rg of NaPSS in the semidilute region (C < 0.3 × 103 kg/m3) can be well expressed by the scaling relation (Rg ∝ C-1/4), while Rg values in the concentrated region are almost constant at the value almost equal to that at ϑ condition. The crossover concentration from the semidilute to concentrated regions was also consistent with our previous studies of viscoelastic properties of polyelectrolyte solutions without added salts.