Higher mechanical performances of CF /PEEK composite laminates via reducing interlayer porosity based on the affinity of functional s‐PEEK

Extensive application of carbon fiber‐reinforced thermoplastic composites has been severely limited by two essential drawbacks including poor interfacial adhesion and harmful void volume fraction between the fiber and the thermoplastic matrix. These drawbacks are due to the surface inertness and high viscosity of thermoplastic during the forming process, respectively. To address these challenges, we report a strategy in which sulfonated polyetheretherketone (s‐PEEK) with strong affinity was successfully obtained as a compatibilizer to modify the interfacial micromechanical properties of carbon fiber ( CF ) reinforced polyetheretherketone (PEEK) composites. Using optimum mass amount of s‐PEEK, the interlaminar shear strength (ILSS) and tensile strength of the improved CF /PEEK composite laminates were 78.6 and 795 MPa, which had been increased more than 45.6% and 11.2% as compared with the original CF /PEEK composite laminates, respectively. The reason was that internal voids and interfacial bonding between CF and PEEK matrix were obviously improved by s‐PEEK. The affinity of s‐PEEK offered new insights to overcome the poor interfacial adhesion for fabricating structural parts with thermoplastic composites. The functionalized CF /PEEK composites have been successfully applied to fabricate a car interior ornament, well meeting the requirements of lightweight and high strength of automobiles. POLYM. COMPOS., 40:3749–3757, 2019. © 2019 Society of Plastics Engineers