Three-dimensional modeling to determine properties of tableting materials on rotary machines using a rotary tableting...

A new three-dimensional modeling technique of tableting data has been used for data measured with a rotary tableting machine simulator. The use of the tableting machine simulator is helpful in this case because a scale up or a change of equipment is easily possible. The model substances used were hydroxypropyl methylcellulose (HPMC 15.000), microcrystalline cellulose (Avicel PH 101), dicalcium phosphate dihydrate (Emcompress) and theophylline monohydrate, four very differently deforming substances. Tablets were produced by simulating a Manesty Betapress with 100 rev./min. The materials were tableted to five graded maximum relative densities (rho(rel, max)) of 0.75, 0.80, 0.85, 0.90 and 0.95. A twisted plane was fitted to the measured data and three parameters: d, the time-plasticity: e, the pressure plasticity and omega, the elastic decompression, resulted for each material at the given rho(rel, max) according to the three-dimensional tableting technique. The results show different parameter-plots for the tableting materials, allowing to differentiate between the tableting characteristics of various substances. Three-dimensional modeling of data from rotary machines is shown to be a valuable tool not only for material characterization on eccentric machines but on rotary tableting machines as well.