Development of nanofilled prepreg for aircraft composite structures

Among the characteristics of primary structures of a Green Regional Aircraft, it appears essential to assure a relevant efficiency with respect to the requirements for lightning strike protection, potential discharge, electrical grounding and electromagnetic shielding. The introduction of advanced composites materials in modern aircraft primary and secondary structures presents special challenges due to their inherent low electrical conductivity. Although carbon fibres are good conductors, polymeric matrixes are excellent dielectric, reducing composite structures conductivity. Cytec Engineered Materials (CEM), relying on the great experience acquired in decades of research, manufacturing and application of advanced epoxy systems to the aerospace market, can bring to this problem the know-how required to reach an advanced and sustainable solution.

We believe that epoxy resins modified with carbon nanotubes have great potential as matrixes for next generation prepreg and composite materials with tailored electrical properties. The objective of this work was the use of carbon nanotubes for a new nanomodified prepreg development. Work package 1 was focused on the selection of an epoxy/nanofilled system and the identification of manufacturing prepreg processes parameters. Work package 2 was focused on the manufacturing and characterisation of coupons and small panels for properties evaluation and final product demonstration. A specific testing campaign was carried out to evaluate the nanomodified composites electrical properties. The test plan included both DC and AC conductivity and electromagnetic shielding efficiency measurements. In addition, the effects of a lightning strike event on a composite structure was evaluated.e