EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

An innovative way to improve the electrical and mechanical properties of fibre-reinforced polymers is the implementation of CNT-doped veils as the surface finishing. They are lightweight nonwoven materials consisting of randomly distributed fibres, characterized by high flexibility and easy handling during operation. CNT-doped veils were developed and are manufactured by the melt-blowing method using a pilot line designed and owned by TMBK Partners Sp. z o. o., Warsaw, Poland.
For this study, CNT-doped veils were manufactured from low temperature copolyamide hot melt (coPA), high temperature polyamide 12 (PA12) and polyphenylene sulphide (PPS). All polymers were mixed with multi-walled carbon nanotubes (MWCNTs) by Nanocyl using an industrial twin-screw extruder. The fabricated nanocomposite pellets were used as initial material in a melt-blowing pilot line. The produced CNT-doped veils have an areal weight around 20 g/m2 and fibre diameter of 30-50µm. In order to prove the concept, CNT-doped veils were incorporated on the surface of glass fibre reinforced polymers (GFRP) and produced by out-of-autoclave method with a liquid polyester resin.
The electrical conductivity measurement confirmed that implementation of CNT-doped veils made of PPS and coPA significantly improved the surface electrical conductivity of GFRP in comparison to the reference panel without veils. At the same time, the impact resistance analyzed by Charpy flatwise was improved by about 29% for PPS veils and only by about 8% and 9% for coPA veil and PA12 veil, respectively. The microstructure observations showed that CNT-doped veil made from coPA and PA12 are not compatible with the polyester used resin while veils made of PPS adhere to the resin resulting in a continous structure without any defects.
The funding for this research was provided by the European Union’s Horizon 2020 research and innovation program under GA 814581 “OASIS”.