ANALYSIS COMPARATIVE OF METHODS TO EVALUATE CONSOLIDATION MECHANISMS IN PLASTIC AND VISCOELASTIC MATERIALS USED AS DIRECT COMPRESSION EXCIPIENTS

In order to better explain the mechanisms of tablet formation, there i s now a greater tendency to investigate particle deformation rather th an bulk deformation of the powder bed. In this sense, measurements of static indentation in tablet to determine compressibility and compacta bility of powders were used. In this work this method, using as hardne ss testing a pyramid instead of a ball into the surface of the tablet under test, is compared to Heckel plots using ejected tablet method. A lso, bonding index, absolute differences between indentation hardness of tablet surfaces and force-displacement curves were used to establis h behaviour of excipients that undergo compression deform plastically and viscoelastic excipients with tendency to deform plastically until applied pressure was exceeded.