Scalable manufacturing of thermally conductive carbon fiber reinforced polyetheretherketone composites via continuous hBN-filled film extrusion

Official URL: https://dx.doi.org/10.1177/08927057261433491

Efficient heat dissipation in carbon fiber reinforced polyetheretherketone (CF/PEEK) thermoplastic composites remains limited due to the inherently low thermal conductivity of PEEK and restricted heat transfer across the laminate thickness, constraining their use in demanding aerospace environments. To address these limitations, this study presents a scalable composite manufacturing strategy based on the integration of the continuously extruded, thermally conductive hexagonal boron nitride (hBN)–filled PEEK films (30 wt.%) with film-stacked carbon fiber laminates. In addition, localized electrospray deposition of hBN onto carbon fiber fabrics is employed to promote interfacial thermal bridging and enhance through-thickness heat transport. The combined processing route encompassing continuous film manufacturing and prepreg-compatible composite fabrication results in simultaneously improving in-plane and through-plane thermal transport pathways. The resulting hierarchical hBN/CF/PEEK laminates exhibit a 21.88% increase in in-plane thermal conductivity (κ∥ = 5.914 W·m−1 K−1) compared to conventional CF/PEEK composites, while electrospray-modified laminates demonstrate a 369.13% enhancement in through-plane thermal conductivity (κ⊥). The incorporation of hBN-filled films also leads to a significant increase in laminate stiffness, with Young’s modulus improving by 54.25%, accompanied by predictable changes in tensile failure mechanisms. By combining continuous extrusion of thermally conductive PEEK films with scalable composite consolidation, this work establishes an industry-relevant manufacturing route for high-temperature thermoplastic composites, offering improved thermal management and mechanical performance for advanced structural applications.