To find out the Theological characteristics of several pharmaceutical semisolid products, experiments were carried out over the temperature range of 20 to 30oC. From continuous shear rheograms obtained with a Ferranti-Shirley cone and plate viscometer, loop area, shear rates, yield values, limiting viscosities and activation energies were calculated. The systems were metastable and their viscosity decreased with time. As the temperature was raised, products studied showed a decrease in viscosity and yield value.
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