Novel high-performance polyamide tapes with glass fiber reinforcement

Polyamide/glass fiber tape roll in the production process. © Fraunhofer IMWS

Fiber-reinforced plastics, which can replace metallic materials and structures, play an essential role with regard to the reduction of CO2 emissions and thus also to climate protection. By means of lightweight construction, raw materials, costs and energy can be saved in the manufacture as well as in the use and recycling of a product.

Consisting of continuous reinforcing fibers and a plastic matrix, unidirectional fiber composite tapes (UD tapes) have better mechanical properties than conventional particle or fiber composite plastics. Due to their versatility, they can be used in various sectors - whether in the automotive industry, the aerospace sector, mechanical engineering or construction of buildings.

In the project "High-Performance-Thermoplastics" (HighPerTherm) the Fraunhofer IMWS together with the project partner DOMO Engineering Plastics GmbH developed novel glass fiber polyamide tapes for use in innovative and cost-efficient lightweight structures for large-scale production. The aim was to expand the range of applications for semi-finished products made of thermoplastic, continuous fiber-reinforced tapes for efficient use in structures that come under high stress.

Laboratory plant for the development of undirectional continuous fiber-reinforced tapes. © Fraunhofer IMWS / Lisa Ossowski

As part of the project, the Fraunhofer IMWS dedicated itself to the optimization and further development of the process technology for the production of continuous fiber-reinforced thermoplastic semifinished products as well as their characterization. The matrix system developed by DOMO Engineering Plastics in the project as well as extensive analyses and optimization of the process parameters led to a significant increase in the mechanical performance of the semi-finished tape products compared to conventional materials. Furthermore, a significant improvement of the processability in the tape process was achieved by the newly developed matrix systems, which enables a significant increase of the fiber wettability in the semi-finished product as well as an improvement of the process long-term stability.

"Through targeted material- and process-specific development steps, we have achieved increases in the fiber volume fraction in the tape semifinished products and determined optimal parameters that enable the production of UD semifinished products with optimized mechanical performance," says Benjamin Tillner, subproject manager for semifinished product development.

DOMO Engineering Plastics GmbH (DOMO EP, Leuna) is a subsidiary of DOMO Chemicals, a manufacturer of polyamide 6 and polyamide 6.6 based in Ghent, Belgium. DOMO EP has been marketing the UD tapes under the commercial name "TECHNYL® Lite" since 2022.

The completed project "HighPerTherm" (funded by Investitionsbank Sachsen-Anhalt) was integrated into the "Lead Market Chemistry and Bioeconomy" of the state of Saxony-Anhalt as well as into the "Performance Center Chemistry and Biosystems Technology".