RESUMO
This paper compares the compressibility and properties of tablets from Prosolv SMCC 90 and a mixture of Avicel PH-102 and colloidal silicon dioxide with a different specific surface. The effect of an addition of the lubricant magnesium stearate on these parameters under varying conditions of mixing and the homogeneity of the lubricant in the mixtures are also examined. Compressibility is evaluated by means of the energy balance of the compression process; the examined properties of tablets are tensile strength and disintegration time. The total energy of compression was increased with compression force, the highest being in Prosolv SMCC 90. Its values did not differ for differing conditions of mixing with the lubricant. Plasticity was slightly decreased with compression force and in the mixture with magnesium stearate it was not influenced by the conditions of mixing. Tablets made from Prosolv SMCC 90 and Avicel PH-102 were stronger than those from the mixtures from Avicel PH-102 and both types of Aerosil. The addition of magnesium stearate markedly decreased the strength of tablets from Avicel PH-102. An increase in the period and frequency of mixing with the lubricant resulted in a further decrease in strength. Disintegration time was longer in tablets from Avicel PH-102 and Prosolv SMCC 90, and it was further prolonged by an addition of magnesium stearate.
