Impact of a non-meltable additive on melt agglomeration with a hydrophobic meltable binder in high-shear mixer.

Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore.
Pharmaceutical Development and Technology (Impact Factor: 1.34). 02/2007; 12(4):371-80. DOI: 10.1080/10837450701369311
Source: PubMed

ABSTRACT The present study aims to investigate the behavior of melt agglomeration with a low-viscosity hydrophobic meltable binder by using a non-meltable additive. The size, crushing strength, and pore size distribution of resultant agglomerates, the rheological, surface tension, and wetting properties of the molten binder, as well as, the flow characteristics of preagglomeration powder blend were determined. The use of additive showed contradictory agglomerate growth-promoting and -retarding effects on the molten binder surface tension and the interparticulate frictional forces. Critical concentration effects of additive corresponded to threshold transition of agglomeration-promoting to -retarding behavior were discussed.

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