The Effect of Compression and Decompression Speed on the Mechanical Strength of Compacts

Abstract

The purpose of this work was to investigate the effect of punch speed on the compaction properties of pharmaceutical powders; in particular, to separate out differences between the effect of the compression and decompression events. Tablets were prepared using an integrated compaction research system. Various "sawtooth" punch profiles were followed to compare the effects of different punch speeds on the crushing strength of the resulting tablets. The loading and unloading speeds were varied independently of one another. In general, when the compression speed was equal to the decompression speed, the tablet crushing strength was observed to decrease as the punch velocity increased. When the compression speed was greater than or less than the decompression speed, the results varied, depending on the material undergoing compaction. Reduction of the unloading speed from 300 to 10 mm/sec for pregelatinized starch and microcrystalline cellulose produced a significant increase in crushing strength, whereas no significant increase in crushing strength was observed until the loading speed was reduced to 10 mm/sec. Reduction of the unloading speed had a similar effect on the direct compression (DC) ibuprofen, however, even greater improvement in the crushing strength was observed when the loading speed was reduced. No improvement in the DC acetaminophen tablets was observed when the unloading speed was reduced, however, a significant increase in crushing strength was produced when the rate of loading was reduced. This work showed that the strength of tablets can be improved and some tableting problems such as capping can be minimized or prevented by modifying the rates of loading/unloading.

Using compression calorimetry to characterize powder compaction behavior of pharmaceutical materials

“…Anhydrous lactose (DT grade, Sheffield Pharma Ingredients, Hoffman Estates, IL), crystalline lactose monohydrate (capsulating grade, Sheffield Pharma Ingredients) and spray‐dried lactose monohydrate (Pharmatose® DCL 11 grade, DMV International, Veghel, the Netherlands), dibasic calcium phosphate dihydrate (Di‐Tab®, Rhodia Incorporated, Cranbury, NJ) and acetaminophen (USP grade, Sigma–Aldrich, St. Louis, MO) were chosen as primarily brittle materials. These materials have been extensively studied and are relatively well characterized 20–24. Additionally, magnesium stearate (Hyqual®‐N.F grade, Mallinckrodt, St. Louis, MO) was characterized since it is frequently used in tablet manufacturing.…”

Non-destructive Determination of Disintegration Time and Dissolution in Immediate Release Tablets by Terahertz Transmission Measurements

“…the porosity, which is the fraction of the volume of voids over the total volume of the tablet. The porosity of a tablet is therefore one of the most important contributors to tablet disintegration and it is directly influenced by the process configuration, such as compaction force and compression speed [2, 3]. …”

Lubricant sensitivity in function of paddle movement in the forced feeder of a high-speed tablet press

“…tableting speed, paddle speed in the forced feeder, fill depth), the same machine and tooling were used throughout the study. 15,[27][28][29] The fill depth was adjusted to obtain tablets of 150 mg, in accordance with the subsequent experiments. Tableting speed was set at 400 tablets per minute (tpm) and force feeder speeds …”