Effect of amino-functionalized MWCNTs addition on mechanical and tribological behaviour of polypropylene-based nanocomposites

Although polypropylene (PP) is lightweight and offers excellent chemical resistance, it shows poor mechanical characteristics for structural applications without reinforcement due to its semi-crystalline structure. This research investigates the mechanical and tribological performance of a polypropylene matrix, incorporating a PP-G-MA compatibilizer and reinforced with both pristine multi-walled carbon nanotubes (MWCNTs) and amino-functionalized multi-walled carbon nanotubes (AMWCNTs) at a weight percentage of 1 wt. %. We made PP/MWCNTs nanocomposite using ultrasonication and magnetic stirring to control the poor dispersion of MWCNTs within the polypropylene matrix, which results in consistent mechanical properties. The performance of the fabricated PP/MWCNTs nanocomposite was compared to that of PP/AMWCNTs using microscopic, mechanical and tribological characterisation techniques. Characterisation was carried out using FTIR spectroscopy to identify functional groups and chemical bonding in the PP matrix, XRD for crystallographic structure and SEM for morphology. Tensile and hardness tests were used to check the materials' mechanical properties, such as their modulus of elasticity, tensile strength and hardness. The tribological characteristics were evaluated using a pin-on-disc tribometer in dry sliding conditions, allowing the assessment of material wear resistance and coefficient of friction. A PP-based nanocomposite reinforced with AMWCNTs exhibits exceptional tensile strength, modulus of elasticity, hardness and wear resistance. This nanocomposite exhibits a 36 % increase in tensile strength and an 87 % increase in wear resistance compared to the pure PP sample. The consistent dispersion of AMWCNTs throughout the matrix and the improved bonding between the AMWCNTs reinforcement and the PP matrix result in the PP/AMWCNTs nanocomposite exhibiting exceptional properties