287894 Nanostructure of Individual Grains Affecting Movement in Densely Packed Material

Tuesday, October 30, 2012: 4:30 PM
Frick (Omni )
Casey Kick1, Xan Voon2 and Kalyana Pingali1, (1)Chemical and Paper Engineering, Western Michigan University, Kalamazoo, MI, (2)Paper Engineering, Chemical Engineering and Imaging, Western Michigan University, Kalamazoo, MI

Ultrathin nanolayers deposited on pharmaceutical particles during the mixing process were investigated with respect to their powder flow behavior. Multiple pharmaceutical formulations were exposed to various shear rate and shear strain conditions in a blender. Samples of lubricated and un-lubricated blends were collected from the blender after the mixing process and their micro and nanostructures were studied under field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The powders with such nanostructures tested for their flow properties in a gravitational displacement rheometer (GDR) showed that the powder flow depended not only on the density of packing of powder bed but also on nanostructures of individual grains. Velocity profiles of powder particles in a tumbling cylinder were tracked at different rotational rates ranging from 1 – 20 rpm. It was interesting to see that the ultra-thin nanolayers affected the velocity distribution of particles within the powder bed as a function of dilation and rotational rate. An attempt made to track the magnitude of each particle average velocity from the interior 3D system is expected to open an innovative approach in particle dynamics.

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See more of this Session: Multi-Scale Approaches in Mixing
See more of this Group/Topical: North American Mixing Forum