Powder densification. 2. Viscoelastic material properties in modeling the uniaxial compaction of powders.
A micromechanical model for predicting the densification of particulate matter under hydrostatic loading was developed to account for the time-dependent response of materials to applied loads. Viscoelastic material response used in the analysis was based upon a standard three-parameter rheological model. Compaction data under closed die conditions were collected using an Instron analyzer for different rates of applied load. Densification during the loading phase of PMMA/coMMA powder, a pharmaceutical polymeric coating material, was well predicted by the proposed algorithm, which contrasts with the prediction implied through a static indentation model. Secondary factors which affect compaction such as die-wall friction are also briefly discussed.
Lum
S K
SK
Faculty of Pharmacy, University of Toronto, 19 Russell Street, Toronto, Ontario, Canada M5S 2S2. susan.lum@utoronto.ca
Hoag
S W
SW
Duncan-Hewitt
W C
WC
D000465:Algorithms; D002626:Chemistry, Pharmaceutical / Q000706:statistics & numerical data*; D004339:Drug Compounding; D004548:Elasticity; D006245:Hardness Tests; D008962:Models, Theoretical; D010316:Particle Size; D011108:Polymers; D019904:Polymethyl Methacrylate; D011208:Powders; D011312:Pressure; D014783:Viscosity
D011108:Polymers; D011208:Powders; D019904:Polymethyl Methacrylate