Extrusion & Compoundierung

The Buss Kneader is a unique compounding extruder. Its most outstanding feature is a special operating principle in which the screw shaft performs a synchronous back-and-forth movement in the axial direction with each revolution. This sinusoidal motion sequence is made possible by a special gear. The characteristic kneading blades on the screw shaft work together with fixed kneading teeth or bolts in the kneader housing. As a result, the raw material components are sheared between the kneading blades and the kneading teeth over an unusually short process length. The oscillating screw shaft also ensures intensive product exchange in the axial direction through multiple dividing, folding, and reorientation of the kneading mass.

This small laboratory unit of Dr. Collin’s has a slot die and a roller and winding unit. The system is designed for processing standard thermoplastics, as the cylinder temperature is limited to 300° C. The system is mainly used for teaching in the practical film extrusion course for students of materials science.

This machine is a co-rotating twin-screw extruder. It is used for the production of compounds from thermoplastics, additives or fillers, as well as the production of polymer blend systems on a laboratory scale. Thanks to the flexibly adjustable screw geometry, the shear energy acting on the plastic melt during processing can be variably adjusted. In this way, the influence of individual screw elements on the dispersion of the fillers or the blend morphology can be specifically investigated. In addition to compounding, rheological tests can be carried out on the materials processed by means of an expansion nozzle.

This co-rotating twin-screw extruder enables us to compound additives, glass, and fillers into polymer matrix systems, or process thermoplastics into blends quickly and efficiently on a pilot plant scale. Thanks to the flexibly adjustable screw geometry, the shear energy acting on the plastic melt during processing can be variably adjusted. In this way, the influence of individual screw elements on the dispersion of the fillers or the blend morphology can be investigated in a targeted manner. Thus, we can respond to a variety of compounding tasks by adjusting screw configuration. In addition, the extruder barrel has two injection points for feeding physical blowing agents, which enable the screening of different formulations for the production of thermoplastic foams. The compounding of high-temperature thermoplastics such as PEEK is also possible with this line configuration.

Location: University of Bayreuth

The Collin extrusion line is a tandem setup consisting of a ZK 25 P twin-screw extruder and an E 45 M single-screw extruder. The other equipment includes a melt pump, gravimetric feeders, a gas metering station, and a pump for liquid metering (e.g. blowing agent).

With this plant, granulate and microgranulate in various sizes can be produced, but also foams and particle foams. We are currently using the system primarily for foam extrusion and particle foam production on a pilot plant scale.

This tandem extrusion line consists of a co-rotating twin-screw extruder and a single-screw extruder. Another single screw can be coupled to the end of the single-screw extruder via a co-extrusion block and the plant can be expanded to a tridem plant.

The line was funded as part of a research project for the production of a thermoplastic printed circuit board. The aim was to produce a three-layer substrate material for conventional printed circuit boards, the core consisting of foamed thermoplastic and the cover layers of compact high-temperature thermoplastic. Of course, this plant configuration can also be used to process other thermoplastics.