IntroductionA wide variety of materials have beenused as binders for pharmaceuticalpreparations, including cellulosic polymers. Over the last several years,newer granulation techniques havecome to the fore. This, the second ina series of Technical Data Sheetsfrom Dow, is designed to meet theneeds of the pharmaceutical formula-tor in addressing these techniquesand the value that METHOCEL* andHPC (hydroxypropyl cellulose) products have as pharmaceuticalbinders. The data presented hereexamines the use of a high shearmixer-granulator, in which the binderswere applied both from aqueous solutions and by adding the bindersto the dry mix followed by granulationwith water.Throughout this series of granulationstudies, it is deemed important to provide data not only on the performance of several different METHOCEL and HPC polymers, butto provide side-by-side comparisondata for other commonly-usedbinders. Therefore, information is supplied for granulations preparedwith two viscosity grades of povidone(polyvinylpyrrolidone, or PVP), acacia,and a pregelatinized starch.Granulation was performed in a Fujivertical high shear mixer-granulator,model VG-25P; this model has a 25 Lbowl. The charge in each granulationwas 4 kg. Granulations were prepared at 3% and 6% binder byweight, with the exception of thepregelatinized starch, which wasused only at 10%. The particle sizedistributions were performed on anATM Sonic Sifter. The apparent andtap densities were determined bystandard techniques. The formulations were compressed using0.5 inch diameter standard concavetooling on an instrumented tabletpress at a series of total compressionforces. Weight and thickness variationas well as tablet hardness and friability were also measured by standard techniques. Final...