The Effect of Wax and Water on Extrusion Forces Using an Instrumented Miniextruder

Abstract

AbstractAn instrumented miniextruder is described and was used to evaluate the effect of wax and water on forces during the extrusion process. Samples as small as 50 g were evaluated. Microcrystalline cellulose (Avicel® PH-101) and acetaminophen were formulated to prepare spheres using methods of extrusion and spheronization. A commercially available wax product, Compritol® (glycerol behenate, N.F.), was added to the formula in levels of 10%. 30%, and 50%, and formulations were granulated with distilled water. As the amount of distilled water or the level of wax was increased in the formulations, a decrease in measured extrusion force was observed. This effect on extrusion forces seemed to be influenced more by the addition of wax than by the level of water. In fact, it was noted that the wax alone decreased the extrusion forces. A comparison between the miniextruder's force readings and power consumption data from an instrumented NICA (model E-140) extruder indicates similar trends.