Abstract: In this paper, the effects of concentration, shearing, temperature, pH, salt-concentration freazing-thawing on the viscosity of plantasan was studied. Results showed that plantasan was non-Newton fluid, and the solution had pseudoplasticity. Apparent viscosity increased with the increase of concentration; the increasing of temperature can reduce the viscosity of plantasan; the viscosity is not affected by the pH 5～11; it has better compatibility with NaCl, Ca2+ obviously improve its viscosity, and the ability is correlated to the concentration of Ca2+ ions. Plantasan had better stabilization of resisting degradation, its viscosity increased with the freezing-thawing.

Key words: plantasan, rheological property, apparent viscosity