Thermoplastic honeycombs bring honeycomb core sandwich panels into a higher performance class. Compared to paper honeycomb cores, thermoplastic honeycombs are much more resilient, especially in a humid environment. A continuous process ensures cost-effective production.

Honeycomb cores made from traditional materials such as paper are well known. A novelty, however, are sandwich panels with cost-effective, continuously produced thermoplastic honeycomb cores made of polypropylene or bio-based PLA. The Belgian specialist for sandwich materials Econcore, Leuven, has launched these honeycomb cores and the necessary production technology on the market under the name Thermhex.

As a honeycomb core material, polypropylene has numerous advantages compared to paper. The core material is insensitive to moisture. Limitations of the mechanical properties in a damp environment are therefore excluded. A general advantage of honeycomb cores is the relatively low use of raw materials. It follows the global trend towards the economical use of resources and the improvement of the carbon footprint.

Continuous process significantly increases profitability

Conventional honeycomb cores are produced in batch production processes. The processes are labor and cost intensive. The process developed by Econcore for the continuous production of honeycomb cores, on the other hand, enables very efficient processing of thermoplastics into honeycomb cores. Significant cost savings are achieved.

The honeycomb cores can be produced directly after the extruder in a continuous process by thermal deformation and folding. Extrusion of the polypropylene granulate creates a film that is formed using the vacuum deep-drawing process. The process was first implemented three years ago at Thermhex Waben GmbH, Halle (Saale), the German subsidiary of Econcore. Today there is a production facility for the production of polypropylene honeycomb cores for the composite material industry. As standard, the cores are laminated inline with a thin thermoplastic barrier film and a PET fleece.

The honeycomb cores are produced automatically

The honeycomb cores are produced automatically. It is integrated in production lines for sandwich panels and special lightweight components. The basis for the continuous inline production of the honeycomb cores and sandwich panels is a rotary vacuum deep drawing process. The innovative folding of the material web creates the sandwich core, which is laminated inline with cover layers in the next step. This creates ready-to-use sandwich panels in one work process.