A physico-mathematical model for the dispersion process in a co-rotating intermeshing twin screw extruder

To modify the properties of polymers, mineral fillers are frequently added during the compounding process. Due to adhesive forces, these pulverized fillers tend to agglomerate. Therefore, in order to achieve a good homogenisation, it is essential not only to distribute them but also to break down the solid agglomerates. A number of relating models have been published, describing observations (agglomerate rupture, erosion, clustering) made during the dispersion process in a mostly isolated manner. Here, a new model considering each observed effect have been developed in order to get a comprehensive description of the dispersion process. To verify the model, it was implemented into a program for the process simulation of co-rotating twin screw extruders (SIGMA [1]), and thus compared to experimental data. It showed that the model could well describe the experimentally determined data.