Twin-screw extrusion downstreaming feeding

Unlike single-screw extrusion, numerous materials, both solid and liquid, are fed downstream in parallel twin-screw extrusion. This provides maximum extrusion flexibility by allowing materials to be introduced into the melt at different stages or locations along the extruder barrel. Examples of downstream feeding advantages are ... 

The corotating twin-screw extruders also offer the choice of multiple ports for liquid injection, venting, and downstream feeding purposes. Eor example, the twin-screw extruder can be readily adapted to combine both the polymer modification and polymer-polymer grafting steps of a reactive blending process into a singlepass, multistage reactive extrusion process. 

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