A new barrier element for corotating twin-screw compounding extruders consists of a forwarding segment separated or sliced by an integral ring-shaped barrier segment.
A new barrier element for corotating twin-screw compounding extruders consists of a forwarding segment separated or sliced by an integral ring-shaped barrier segment. Elements are set at 90° angles to each other. Offsetting the elements creates more open space, in which resin pools and is stretched before being compressed as it is forced over the barrier ring. The new mixing element has been in development for several years by Extricom GmbH (formerly Blach GmbH) in Lauffen, Germany, and is offered here by Century Inc., Traverse City, Mich. The element reportedly imparts less shear than conventional mixing blocks and achieves fine dispersive mixing of powders, pigments and additives through melt elongation.