In this paper, the viscoelastic properties of partially hydrolyzed polyacrylamide(HPAM) solution were investigated with a cone and plate measuring system. Results show that the existence of viscoelastic structure in HPAM solution can be detected quite sensitively by the apparatus. Meanwhile, we also obtained the relationship between the elastic component and the viscous component. It is shown that there exists a maximum value corresponding to the elastic component of solution at the HPAM concentration range of 0.1~0.4 g·L-1. At shear rate =0.36 s-1, high molecular weight hydrolyzed polyacrylamide solution has apparent viscoelastic properties. With the addition of salts, viscoelastic properties of HPAM solution decrease. Moreover, the network structures in HPAM solution are destroyed at higher salt concentration, and the elastic behaviors vanish. For PAAM(polyacrylamide) solution, viscoelastic properties weren′t observed at the range of 0.36~1.36 s-1. A weak viscoelasticity was observed only when ≥1.65 s-1.
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