Material structure, agglomerates

Flow induced phase inversion (FIPI) has been observed by the author and applied to intensive materials structuring such as agglomeration, microencapsulation, detergent processing, emulsification, and latex production from polymer melt emulsifica-A diagrammatic illustration of FIPI is shown in Fig. 4. When material A is mixed with material B, in the absence of any significant deformation, the type of dispersion obtained [(A-in-B) or (B-in-A)] is dictated by the thermodynamic state variables (TSVs) (concentration, viscosity of components, surface activity, temperature, and pressure). If the... 

Many fluids show a decrease in viscosity with increasing shear rate. This behavior is referred to as shear thinning, which means that the resistance of the material to flow decreases and the energy required to sustain flow at high shear rates is reduced. These materials are called pseudoplastic (Fig. 3a and b, curves B). At rest the material forms a network structure, which may be an agglomerate of many molecules attracted to each other or an entangled network of polymer chains. Under shear this structure is broken down, resulting in a shear... 

Measurements of particle porosity are a valuable supplement to studies of specific surface area, and such data are particularly useful in the evaluation of materials used in direct compression processes. For example, both micromeritic properties were measured for several different types of cellulosic-type excipients [53]. Surface areas by the B.E.T. method were used to evaluate all types of pore structures, while the method of mercury intrusion porosimetry used could not detect pores smaller than 10 nm. The data permitted a ready differentiation between the intraparticle pore structure of microcrystalline and agglomerated cellulose powders. 

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