It was found that the interface effects in viscous capillary flow influenced the process of viscosity measurement greatly, and the abnormal viscosity behaviors of polyelectrolytes as well as neutral polymers in dilute solution region were ascribed to interface effect. According to this theory, we have reviewed the previous viscosity data of derivatives of poly-2- vinylpyridine reported by Maclay and Fuoss first. Then, the abnormal viscosity behaviors of a series of sodium polystyrene sulfonate samples with various molecular weights in dilute aqueous solutions were studied further. The solute adsorption behaviors and structural information of polymers have been discussed carefully.
