Fractal Dimension of Powders for Pharmaceutical Dusting Powders

Overview

The paper examines the use of the fractal dimension for the expression of the shape of randomaggregates of primary particles of four powders for pharmaceutical dusting powders. The valueswithin a range from 1.14 to 1.24 are compared with the results of the equilibrium gravitationalclassification within a range from 15 to 45 mm. Vacillation of the fractal dimension is influenced bythe values of the specific surface determined from the parameters of the RRS-distribution ofelutriation. The fractal dimension extends the morphological characteristics of powders. For theneeds of pharmaceutical technology it is, however, necessary to specify better the conditions of itsdetermination, above all in the selection of a suitable range of the dimension of evaluation („walk“)with regard to the largest dimension of the aggregates of powders.

Key words:
fractal dimension – powders – aggregates – elutriation – specific surface