A global computer software for polymer flows in corotating twin screw extruders

Abstract

International audienceA global computation model for self-wiping corotating twin screw extruders is proposed. Based on a 1D approximated approach, it has been validated by comparison with experimentation and more sophisticated numerical models. It allows one to obtain, for any screw profile including left-and right-handed screw elements and kneading discs, the profile along the screws of the main flow variables, such as pressure, mean temperature, residence time, and filling ratio. Owing to the approximations made, this model can be easily and rapidly run on a personal computer or a workstation. Important applications may be found in screw profile design, scaleup, compounding or reactive extrusion

High shear dispersion of tracers in polyolefins for improving their detection

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Twin-screw extrusion impact on natural fibre morphology and material properties in poly(lactic acid) based biocomposites

“…linked by the relation F R = A × (Q/n) (Vergnes et al, 1998), where A is a constant value depending on the extruder geometry and the screw profile that were kept the same for all the study. Actually, if the amount of matter introduced in the machine became bigger, it was compensated by lower residence time along the screws due to a faster screw rotation.…”

Properties and Biodegradation Nature of Thermoplastic Starch

“…For that various types of plasticizers such as glycerol, water, urea formamide etc are used during the formulation. The characteristics of mechanical work and flow (temperature, pressure, residence time, energy) during the preparation of TPS are known and modeled [Agassant et al, 1996, Vergnes et al, 1998]. A specific mechanical energy (SME) higher than 300kJ/g is necessary to achieve a complete destructuration of starch granules.…”

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