Delta Kunststoffe AG of Weeze, Germany, is making electrically conductive polymer compounds on a ZSK MEGAvolume PLUS twin-screw extruder from Coperion GmbH.
The Coperion extruder mixes conductive carbon black into the melt. Base polymers processed in this fashion include polypropylene, polyethylene, polystyrene and nylon 6.
The extruder, equipped with screws with diameters of 76 millimeters, produces compounds with a carbon black content between 15-40 percent, depending on the requirement, from antistatic to readily conductive. Output ranges from 2,205 to 3,307 pounds an hour.
The deep-flighted screws permit downstream metering of the conductive carbon black into the already molten base material, via a ZS-B twin-screw side feeder, regardless of the amount to ve added and the extruder's output rate. Also, the screws feature special mixing elements that distribute the carbon black uniformly within the polymer matrix.
The melt is degassed using a ZS-EG twin-screw devolatization unit.
Coperion, of Stuttgart, Germany, said the large free screw volume of the ZSK MEGAvolume PLUS considerably minimizes shear, and that gentle treatment, combined with the direct downstream metering of the carbon black, preserves the conductive properties of the carbon black.
The extruder maker's U.S. unit, Coperion Corp., is in Ramsey, N.J.
Tel. 201-327-6300, fax 201-825-6450, email [email protected].