Improving the electrical conductivity and fracture toughness of carbon fibre/epoxy composites by interleaving MWCNT-doped thermoplastic veils

Publication date: Available online 8 August 2019Source: Composites Science and TechnologyAuthor(s): Dong Quan, Chiara Mischo, Xiping Li, Gennaro Scarselli, Alojz Ivanković, Neal MurphyAbstractPolyethylene terephthalate (PET) veils doped with and without multi-walled carbon nanotubes (MWCNT) were used to interlay a unidirectional carbon fibre/epoxy composite. The electrical and fracture properties of the laminates were studied. Significant improvements in the Mode-I fracture energy (GIC) and Mode-II fracture energy (GIIC) of the laminates were observed for interlaying the original PET veils. This was associated with a considerable drop in the electrical conductivity. Doping a small amount of MWCNTs on the PET interlayers strikingly improved the electrical conductivity of the laminates, especially in the through-thickness direction. However, it also resulted in moderate decreases in GIC and GIIC. Interestingly, this was caused by an improved PET fibre/epoxy adhesion due to the presence of the MWCNTs on the PET fibres, that restrained the PET fibre bridging in the fracture process. The experimental results demonstrated the potential of developing both highly electrically conductive and tough laminates by interlaying MWCNT-doped thermoplastic veils.
Source: Composites Science and Technology - Category: Science Source Type: research