Granulation granule strength

The effect of different bonding mechanisms, and of the primary particle size on granule strength, is shown in Figure 5.2. Four mechanisms (Capes, 1979 Sherrington and Oliver, 1981) need to be considered. First, intermolecular forces. The attractive force between particles is inversely... 

In scale-up from laboratory quantities (up to 10 kg) to production batches (300 kg and up), bed depth increases significantly. The most notable consequence is an increase in finished product bulk density, typically in the range of 15% to 20%. In some instances, this is a disadvantage (if product is packed by volume and a low density is desired). However, granule strength is usually greater as a result of the decreased interstitial void space. 

Table 9. Effect of agglomerating liquid composition on granule strength in impact load tests...

Formulations are optimized with additives to control granule strength, dissolution, chemical stability, viscosity, stability on storage, or fungal growth. They can also contain toning dyes and auxiliaries to improve their efficiency in a given application. 

Adhesion and cohesion forces in the immobile liquid films between individual primary powder particles. These forces may not contribute significantly to the final granule strength once the granules have been dried. These forces arise from the thin liquid layers around particles that may be generated due to moisture uptake by the powders. This immobile liquid film tends to decrease the inter-particle distances leading to an increase in the van der Waals forces between particles. 

In solid dosage forms, granulation is frequently used to improve excipient properties such as flowability, compactibility, bulk density, granule strength, dissolution rates, and so The granulation process... 

For a theoretical system of moist, spherical, monodisperse agglomerates, granule strength is given by the following equation ... 

Temperature (+/- Inlet air temperature Granule strength/friability ... 

Granule strength Adams xf, Kawakita of Adams Kawakita Heckcl... 

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