Development of conductive coated Polyether ether ketone (PEEK) filament for structural health monitoring of composites

Taking full advantage of its high temperature resistance and high elongation properties, conductive coated Polyether ether ketone (PEEK) filament yarn can be used as a textile-based electro-conductive functional element, especially as a strain sensor. This paper describes the development of electric conductivity on an inert PEEK filament surface by applying silver (Ag) metallic layers using a wet chemical procedure. To ensure good adhesion properties of the Ag layer, the PEEK monofilament surface is treated with an atmospheric pressure plasma process and a subsequent coating of a polyamine based adhesion promoter. Measurements of electrical resistance of Ag coated PEEK filament yarns are performed before and after their integration into the textile reinforced thermoplastic composite. The electro-mechanical characterisations show the potential of Ag-coated PEEK for structural health monitoring in textile-reinforced composites. Furthermore, the electro-mechanical behaviour of Ag coated PEEK is analysed mathematically and compared with experimental values.