The melt-fracture is one of the most serious problem in the extrusion of thermoplastic materials. This is a flow instability that appears as an almost regular distorsion of the extruded material. After a panorama on the known experimental facts, a mathematical model is given in such a way to emphasize some essential parameters controlling the start of this phenomenon. In fact has been decovered an adimensional number, $ W_c$, ({\it Weissenberg number}), characterizing the start of flow instability in all melt polymers. This allows us to determine the extrudibility characteristics of polymeric materials.
Modello matematico sulla formazione della melt-fracture nei polimeri fusi / Prastaro, Agostino. - In: QUADERNI DELL'INGEGNERE CHIMICO ITALIANO. - ISSN 0370-288X. - STAMPA. - 3-4:13(1977), pp. 37-44.
Modello matematico sulla formazione della melt-fracture nei polimeri fusi.
PRASTARO, Agostino
1977
Abstract
The melt-fracture is one of the most serious problem in the extrusion of thermoplastic materials. This is a flow instability that appears as an almost regular distorsion of the extruded material. After a panorama on the known experimental facts, a mathematical model is given in such a way to emphasize some essential parameters controlling the start of this phenomenon. In fact has been decovered an adimensional number, $ W_c$, ({\it Weissenberg number}), characterizing the start of flow instability in all melt polymers. This allows us to determine the extrudibility characteristics of polymeric materials.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
