Thermoplastic Foam Injection Molding

In the interest of minimizing the use of resources,the importance of manufacturing foamed components in large quantities at reproducible quality is continuously increasing in the context of polymer processing. Thermoplastic foam injection molding is one way of producing foamed structures in the injection molding process. This technology offers both component-specific advantages, such as lower density, less material usage, higher specific bending stiffness and lower warpage, as well as process-specific advantages, such as reduced melt viscosity, lower cavity pressures and therefore lower clamping forces, and the elimination of holding pressure. Components foamed by injection molding are generally recyclable.

In addition, thermoplastic foam injection molding can also be used for the highly automated production of thermoplastic sandwich structures. In this process, consolidated face sheets with thermoplastic matrix – if necessary preformed – are heated and inserted into the injection mold. The gas loaded melt is subsequently injected between these cover layers and foamed, creating the foam core “in-situ”.

As part of a grant for research infrastructure from the state of Rhineland-Palatinate, the existing injection molding technology at IVW is being expanded for thermoplastic foam injection molding. For this purpose, the existing injection molding machine with a clamping force of 400 tons will be equipped with a special plasticizing unit and connected to a gas metering station. In addition, a suitable experimental mold with integrated sensor technology will be designed. All process variables relevant to foam injection molding can thereby be recorded in the production cell and evaluated for use in process and component development.

With this project, the research infrastructure of IVW is expanded by a promising technology for production
of sustainable lightweight parts.