Effect of functionalization and concentration of carbon nanotubes on mechanical, wear and fatigue behaviours of polyoxymethylene/carbon nanotube nanocomposites

The main focus of this work is to improve the mechanical, wear and fatigue behaviours of polyoxymethylene (POM) by reinforcing with carbon nanotubes (CNTs). To improve compatibility between CNTs and POM, the surface of the CNTs was modified by various methods of functionalization like carboxylation, silanation, carbonylation and amination. The functionalized CNTs were characterized by Fourier transform infrared spectroscopy to confirm the different functional groups attached to the surface. POM/CNT nanocomposites were developed with functionalized CNTs in different concentrations varying from 0.25 to 2 wt%. Nanocomposites with 1 wt% of silanated CNTs resulted in maximum improvement of tensile, flexural and impact properties. Furthermore, experimental results on fatigue and dry sliding wear tests revealed that the fatigue strength, specific wear rate and friction coefficient are sensitive to functionalization and concentration of CNTs.