The material can be further and thoroughly mixed in the die before being extruded as a uniform melt through the die.
It can provide an appropriate residence time for the material in the die head. Too short a residence time affects the quality of the melt, while too long a residence time promotes degradation and cross-linking of the melt, damaging the original physical properties of the material.
It can ensure a low melt pressure and a stable extrusion balance within the die head.
It can ensure a low material temperature within the die head to prevent lateral flow and premature oxidation during extrusion.
