Measurement of the Thermal Energy Evolved upon Tablet Compression

The increase in temperature that occurs when a granulation or powder is compressed into a tablet has long been of interest to pharmaceutical scientists. Not only can this rise in temperature be indicative of differences in formulations which affect their performance during the tabletting process, but it may also cause unforeseen changes in the final tablet. Exact measurements of this temperature rise and of the thermal energy released have proven to be elusive. The diversity in equipment used approximately equals the number of published studies. This is the first report in which an accurate temperature probe has successfully been placed within the powder bed being compacted. Using a measurement system of original design, both the temperature rise and thermal energy evolved have been measured for single component systems comprised of Avicel, calcium carbonate, Corn Starch USP, and sulfathiazole. Extension of this work will deal with reactive multicomponent systems