A method of calculating the thixotropic area of non-Newtonian dispersions

Abstract

Thixotropic area is one of the parameters for evaluating the rheology of thixotropic (non-Newtonian) dispersions. A method of determining this parameter has been suggested. This method involves the resolution of a polynomial, which represents the ascending curve of the rheogram. The area under the curve is determined by integrating the resolved equation within specified limits of shear stress. The difference between this area and the area of a trapezium formed by the descending curve, the vertical lines drawn from the specified limits of shear stress and the shear stress axis, forms the thixotropic area of the dispersion.

Key words: Non-Newtonian dispersions, thixotropic area, aluminium hydroxide gel, antacid formulation.

Journal of Pharmaceutical and Allied Sciences Vol.2(2) 2004: 237-243