Experimental Investigation of Compressive and Wear Behavior of Polymer/CNT Nanocomposites

Poly(methyl methacrylate) (PMMA) has wide usage in structural and tribological applications, but low compressive strength and poor wear resistance limit its performance in load-bearing sliding conditions. This study investigates the impacts of ultra-low concentrations of multi-walled carbon nanotubes (MWCNT) on flexural properties at 0.1, 0.5, and 1 wt. % on the mechanical and frictional behavior of PMMA nanocomposites. The mechanical performance was analyzed by load–displacement and stress–strain analysis, and the wear behavior was studied using a pin-on-disk tribometer under dry sliding conditions. Raman spectroscopy confirmed the successful incorporation of MWCNTs while maintaining their graphitic structure within the polymer matrix. The incorporation of 0.1 wt.% CNT markedly enhanced compressive strength from roughly 85 MPa to around 127 MPa, reflecting an improvement of over 50%, along with augmented deformation stability. Increased CNT concentrations led to diminished mechanical performance owing to nanotube aggregation and stress concentration. Nonetheless, the inclusion of CNT significantly improved wear resistance, decreasing wear rates by almost 95%. These results underscore the essential importance of nanotube dispersion in enhancing the mechanical and tribological properties of PMMA nanocomposites.