Enhanced mechanical and tribological properties of polyamide using carbon nanotube

The present work deals with the development of nanocomposite materials to increase the mechanical and wear properties by introducing multiwall carbon nanotube (MWCNTs) fillers into the polymer matrices. In the present study, MWCNTs with 0.2, 0.3, 0.4, and 0.5 wt% loading was mixed with PA11 pellets by using a melt mixing technique to create a family of PA11/MWCNT composites. Scanning electron microscope (SEM), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD) were utilized to determine the characterization of MWCNTs and the degree of dispersion of MWCNTs in the PA11. Tensile, flexural, and hardness tests have been performed in order to measure the mechanical properties such as tensile modulus, tensile strength, and elongation at fracture. The creep and creep recovery were studied using dynamic mechanical thermal analysis (DMTA). The wear behavior was investigated by using a pin-on-disk wear tester under dry sliding condition at different normal loads. The result shows that the tensile modulus and flexural modulus for PA11/MWCNT 0.5 wt% increase by 20% and 34.8%, respectively. In addition, the creep strain is increased with temperature and decreased with the MWCNT fillers which indicates an enhanced performance at short time scales. Furthermore, the wear rate for PA11/MWCNT 0.5 wt% decrease by 44% at 10 N and 22% at 5 N. Therefore, the incorporation of MWCNT fillers with PA11 has significantly enhanced the mechanical and tribological properties. Different applications in many fields can be benefited by these results as the worldwide trend is to replace steel with a reinforced polymer.