Ayşenur Gül, Ali Reza Kamali
Carbon nanotube (CNT) reinforced epoxy nanocomposites were prepared using a solvent-assisted dispersion method and characterized to evaluate their structural, mechanical, and thermal behaviour. X-ray diffraction (XRD) confirmed the presence of CNTs in the polymer matrix through the characteristic (002) reflection, while scanning electron microscopy (SEM) revealed that CNTs were found to be uniformly embedded within the epoxy matrix, showing limited agglomeration and strong interfacial bonding. Fourier-transform infrared spectroscopy (FTIR) supported these observations by revealing absorption bands associated with C=C stretching, C–O–C ether linkages, and O–H vibrations, indicating chemical interactions between CNTs and the epoxy network. Mechanical testing showed that CNT concentrations of 0.25–0.50 wt.% provided the most effective reinforcement, with notable and measurable improvements in tensile and compressive strength as well as modulus. At higher CNT loadings, however, agglomeration led to reduced tensile performance, despite compressive strength remaining comparatively stable. Thermal conductivity increased steadily with CNT addition, from 0.2143 W/m.K for neat epoxy to 0.2435 W/m.K at 0.75–1.00 wt.%, with the most pronounced improvements observed above 0.25 wt.% due to the formation of more efficient conductive pathways. Overall, these findings suggest that low-to-intermediate CNT loadings achieve a practical and useful balance between strength and thermal conductivity while avoiding the drawbacks of excessive filler content. Effective dispersion of nanotubes is a critical factor that governs the mechanical and thermal behaviour of the composites. These results indicate that CNT/epoxy nanocomposites produced under optimized conditions can serve as lightweight, mechanically reliable, and thermally stable materials, making them attractive candidates for advanced applications in aerospace, automotive, and energy-related sectors where both structural performance and efficient thermal management are required.