A composite SSEM_SF computer model of solids conveying, melting and melt flow has been developed for starve fed single screw extrusion. Experimental studies have been carried out for starve fed/flood fed extrusion of several polymeric materials, incl. polyblend materials using screws of conventional and mixing configurations. “Screw Pulling-out Technique” has been applied to investigate the material melting and flow in the machine. Pressure and temperature were measured, as well as power consumption was evaluated. CSM type of melting mechanism (contiguous solids melting) was observed for flood fed extrusion, but it was not observed for starve fed extrusion. A new melting mechanism for polyblend materials has been proposed, including conductive melting in the starve fed region, and dispersed melting in the fully filled region. A backward scheme of calculation has been applied for composite modeling. Screw pumping characteristics based on the 3D non-Newtonian solution have been used to calculate pressure gradient back along the screw. A composite SSEM_SF model has been applied for simulation of the experimental runs. The model predictions were consistent with experimental data.
