Partial hydrolyzed polyacrylamide (HPAM) is a polyelectrolyte. Due to the electrostatic repulsion of intramolecular -COO- groups

the polyacrylamide molecules in water are extended to form filamentous structure

and its aqueous solution has very high intrinsic viscosity.This paper presents a detailed study on the relationship between structure and viscosity of solution. The influences of hydrolysis degree of PAM molecular weight of HPAM and salt concentration on the morphology have been discussed.