INFLUENCE OF THE PARAMETERS MOLECULAR-STRUCTURE AND GRANULARITY ON THE COMPACTIBILITY OF A POWDER

The aim of this study was to determine whether it is possible to obtai n better characterization of materials in order to find out if these o ne are suitable in Quality Assurance for direct tableting. We tried to show that a methodological approach combining chemical, physical and technological aspects could control the direct compression process. We chose orthoboric acid as a study model for the direct compression. Fr om a chemical point of view, our findings show only one crystalline mo lecular structure (RX, DSC and Pycnometry) which means an homogeneous chemical system. Concerning the particular state (Sieving and Microsco pic approach), granularity is very different between the two forms, '' crystalline'' ABC and ''powder'' ABP. Technological studies show a the ological and mechanical difference, as it is demonstrated, on the one hand by the behaviour of the bulk powder (Volumenometer), on the other hand by the feasibility on the machine (Alternative EKO). We explain this difference of behaviour by only the granularity aspect. Consequen tly, we think that in this case, controling the granularity means cont roling this direct tableting process.