Effect of compression speed and pressure on the physical characteristics of maltodextrin tablets.

The present paper studies the effect of applied pressure (0-300 MPa) and compression speed (8 and 40 cycles/min) on the physical characteristics of four varieties of maltodextrins for direct compression. The materials were tableted by using a single-punch tablet machine. On the basis of the mechanical properties it seems to be reasonable to propose a limit in the plastic deformation and consequently bonding between particles. This limit could be approximately 90 MPa, and it was almost independent of the variety compressed. Disintegration behavior and, most probably, release properties are related with this limit; i.e., mechanical parameters and disintegration time increased as applied pressure was increased up to this limit. Above this limit, no differences of note were found. The different movement of particle layers in the single-sided eccentric profile led to the computation of differences between upper and lower tablet hardness surfaces, which were indicative of a consolidation mechanism. The differences obtained were indicative of the plastic deforming nature of maltodextrins.