Preparation and properties of carbon nanotubes/carbon fiber/poly (ether ether ketone) multiscale composites

The carbon nanotubes/carbon fiber/poly (ether ether ketone) (CNTs/CF/PEEK) multiscale composites with excellent properties were prepared by introducing treated CNTs (t-CNTs) into CF/PEEK composites using prepreg spraying method. The effect of t-CNTs content on the mechanical performance of composites such as interlaminar shear strength (ILSS), flexural strength and flexural modulus were investigated. The results indicated that the ILSS, flexural strength and flexural modulus of CNTs/CF/PEEK composites were increased by 35.8%, 25.4% and 23.7% after 0.5 wt% t-CNTs introducing. The surface of prepregs and cross-section of the composites displayed evenly t-CNTs dispersion and strong fiber-resin adhesion by scanning electron microscope observation. With the addition of t-CNTs, the electrical conductivity and thermal conductivity of CNTs/CF/PEEK composites were also markedly improved, in comparison with that of CF/PEEK composites. This suggested that the prepreg spraying method was an effective approach to coat t-CNTs on CF/PEEK prepregs and enhance the performance of CNTs/CF/PEEK composites.