Influence of degassing on hot-melt extrusion process

Abstract

The present study aimed to evaluate the effect of degassing on an extrusion process, with respect to extrudate quality and drug release properties. Processed formulations were extruded with and without a degassing vent port at various locations along the barrel. All the experiments were performed under constant processing temperature, feeding rate, and screw speed. During the extrusion process, torque and pressure were monitored and recorded. The degassing process was beneficial when used over a conveying section after a mixing section. This is attributed to the large surface area available on the conveying elements, which minimizes the internal volume of the processed material, thereby facilitating the escape of entrapped gases. Degassing enhanced the homogeneity, physical appearance, and drug release properties of all the formulations. Furthermore, the degassing process also enhanced the cross-sectional uniformity of the extruded material, which is beneficial for visual monitoring during processing. Degassing considerably reduced the post-extrusion moisture content of Formula D3, which contains the highly hygroscopic polymer Kollidon® 17 PF, suggesting that the greatest influence of this process is on hygroscopic materials. The reduction in post-extrusion moisture content resulting from the inclusion of a degassing vent port, reduced fluctuations in the values of in-line monitoring parameters such as pressure and torque. Employing a degassing unit during hot-melt extrusion processing could help increase process efficacy and product quality.

Applications of Dynamic Mechanical Analysis in the Engineering of Amorphous Solid Dispersions

“…33 Temperature and screw speed are among the most important factors affecting both the HME processing and final ASD products through the distributive mixing and solubilization of APIs. 34 Screening of various compositions can be performed effectively with the rheological study of drug: polymer physical mixtures (PMs). 30 The softening temperatures of the PMs and viscosity at various shear rates can help guide the initial selection of composition, temperature, and shear conditions to carry out HME.…”

Hot-Melt Extrusion as an Advantageous Technology to Obtain Effervescent Drug Products

“…In addition, the HME process usually presents a more simplified scale-up than other industrial processes [49]. Particularly, HME production of effervescent products could be associated to an open zone in the barrel, therefore any water vapors could be eliminated by the degassing process of the material, producing filaments with even lower moisture content [50,51].…”

Investigation on the effects of Cloisite 30B and copolymer (ethylene and butyl acrylate) reinforcement with polypropylene thermoplastic by melt intercalation method

“…The moisture or any other form of impurities present in PP/C30B/EA nanocomposites’ melt stream has to be removed for ensuring the better properties of the processed polymer. 33 During the manufacturing of PP/C30B/EA nanocomposites, vacuum is applied to the vented barrel to remove the moisture and other impurities from the PP/C30B/EA nanocomposites. The vacuum pressure applied depends on the melting point of the material.…”