Melt agglomeration mechanism

Two modes of melt agglomeration based on the elementary mechanisms have been proposed—distribution and immersion. In agglomeration by the distribution mode, a distribution of molten binding liquid on the surfaces of primary particles will occur, and agglomerates are formed via coalescence between the wetted nuclei (Fig. 3). In agglomeration by the immersion mode, nuclei are formed by immersion of the primary particles onto the surface of a droplet of molten binding liquid (Fig. 3). The distribution of molten binding liquid to surfaces of... 

Eliasen, H. Kristensen, H.G. Schaefer, T. Growth mechanisms in melt agglomeration with a low viscosity binder. Int. J. Pharm. 1999,186, 149-159. 

Seo A, Holm P, Schaefer T. Effects of droplet size and type of binder on the agglomerate growth mechanisms by melt agglomeration in a fluidized bed. Eur J Pharm Sci 2002 16 95-105. 

Abberger T, Seo A, Schaefer T. The effect of droplet size and powder particle size on the mechanisms of nucleation and growth in fluid bed melt agglomeration. Int J Pharm 2002 249 185-197. 

Also, the granulation process can be used to influence the dissolution behavior of a tablet, e.g., to gain a drug with sustained release characteristics. In this case melt agglomeration by hot melt extrusion is a widespread process where a particular excipient is able to melt and mechanically stabilizes the agglomerates after cooling (1,2). This excipient embeds the active components in a so-called matrix and alters the dissolution characteristics from immediate release to a diffusion controlled sustained release. 

The drying of solutions and the solidification of melts form an integral part of many of the size enlargement methods discussed in other chapters of this book. These are common mechanisms to harden agglomerates and prepare them for further processing and use. A number of the machines men-... 

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