Carbon nanotubes- A powerful nano-filler for enhancing the performance properties of polyetherketoneketone composites and adhesives

Abstract In the current study, the potential of MWCNTs (functionalized with hydroxyl group) was explored for enhancing the performance properties of a high-performance polymer matrix, i.e., polyetherketoneketone (PEKK). The dispersion and distribution of MWCNTs (0, 0.1, 0.3, 0.5, and 1 wt %) were ensured by rigorous probe-ultra sonication and confirmed with FESEM (Field Emission-Scanning Electron Microscopy). The nano-composites and their surfaces were characterized for physical, thermal, and mechanical properties, including tensile strength, micro-hardness (Scratch and Vickers's), lap shear strength (LSS), contact angle, surface free energy and friction. MWCNTs led to reduction in friction but enhancement in mechanical properties. It was concluded from the studies that the addition of MWCNTs at 0.3 wt % led to best combination of performance properties such as LSS, tensile strength and modulus, micro-hardness, etc. The current study concluded that among the three effects offered by MWCNTs in the adhesives on LSS viz. reinforcement (a positive one), increasing interfacial adhesion with the adherend (a positive one) and friction–reducing (a negative one), the first two overweighed the third one significantly and led to a net improvement in LSS. It was also concluded that PEKK proved to have highest LSS followed by PAEK (Polyaryletherketone) and then PEEK (polyetheretherketone). Their nanocomposites also showed the same trend.