Processing and Characterization of Conductive Polyether Ether Ketone/Carbon Nanotube Monofilaments and Core–Sheath Filaments
Keywords:
Poly ether ether ketone, carbon nano tubes, sensor yarn, electrical conductivity, mechanical properties, thermoplastic compositeAbstract
The increasing demand for lightweight, high-performance materials has driven the development of textile-reinforced composites with integrated sensing capabilities. While thermoset-based composites have established sensor integration strategies, thermoplastic composites face challenges due to high processing temperatures. This study presents a novel approach to produce high-temperature-resistant, electrically conductive polyether ether ketone with multi-walled carbon nanotubes (PEEK/MWCNT) monofilament and core-sheath (PEEK-MWCNT/PEEK) filament yarns suitable for textile processing and structural health monitoring. Filaments were produced using a twin-screw extrusion site and a bicomponent melt spinning plant, systematically varying MWCNT content (1.0–7.0 wt.%) and process parameters. Differential scanning calorimetry revealed that MWCNTs influence PEEK crystallinity, glass transition temperature, and thermal transitions, while scanning electron microscopy (SEM) images confirmed filler dispersion and morphology. Mechanical testing demonstrated increased stiffness and tensile strength with higher MWCNT loading, while elongation at break decreased. Integration of conductive filaments into glass fiber/polypropylene (GF/PP) composites maintained or slightly improved composite mechanical properties. Electrical contacting via crimping combined with conductive epoxy provided stable, low-resistance connections. The results demonstrate that PEEK/MWCNT sensor yarns are suitable for high-temperature, textile-reinforced thermoplastic composites, offering a robust platform for intrinsically conductive, processable, and mechanically stable structural health monitoring systems.
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