| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 238262 | Powder Technology | 2010 | 8 Pages |
Empirical relationships between compaction conditions and changes in small-angle X-ray scattering (SAXS) patterns were reported previously, suggesting a novel method for studying powder compaction [1,2]. In the present work, a more quantitative model was developed to explain the changes in SAXS patterns observed for pre-gelatinised starch and microcrystalline cellulose. Analysis of SAXS data suggested (approximately) power-law scattering behaviour for these materials, which was consistent with their hierarchical intragranular morphologies, including nanoscale porosity, as described elsewhere [3]. Observations using XµT suggested affine deformation of granular shapes during compaction. Based on the assumption that the sub-granular morphology also deformed affinely, a description of the azimuthal variations in scattering intensity was developed, which gave very close agreement with experimental observations. Based on this model, it appeared that SAXS could be used to obtain quantitative estimates of granule deformation specifically, isolating this component from the other mechanisms operating during powder compaction.
Graphical abstractX-ray microtomography (XµT) was used to investigate granule deformation within a compacted powder bed. Based on these observations, a model was developed that closely matched the changes in small-angle scattering (SAXS) observed for compacted microcrystalline cellulose (MCC) and pre-gelatinised starch (PGS). On this basis, it appeared possible to extract quantitative information from SAXS concerning granule deformation.Figure optionsDownload full-size imageDownload as PowerPoint slide
