Polyoxymethylene Reinforced With Multiwalled Carbon Nanotubes and Tungsten Disulfide Hybrid Nanocomposites: Experimental and Micromechanical Studies for Gear Applications

ABSTRACT The study investigates the synergistic impact of nano‐sized multi‐walled carbon nanotubes (MWCNT) and tungsten disulfide (WS ₂ ) in the polyoxymethylene (POM) polymer matrix. The proportion of MWCNT is maintained at 1 wt.%, while WS ₂ varied at 0.5, 1, and 1.5 wt.%. The nanocomposites are prepared using the melt‐compounding technique with a twin‐screw extruder and molecular interactions were analyzed using Fourier‐transform infrared spectroscopy (FTIR). The compounded materials are palletized and injection molded into ISO test specimens for mechanical characterization. Scanning Electron Microscope is used to examine the fractured surfaces of tensile‐tested samples to evaluate failure mechanisms and nanofiller dispersion. Differential scanning calorimetry and thermogravimetric analysis are performed to obtain thermal properties and thermal stability. The POM/MWCNT (1 wt.%)/WS ₂ (1 wt.%) nanocomposites exhibited enhanced mechanical and thermal performance compared to neat POM. The tensile strength, flexural strength, and flexural modulus increased by 25%, 33%, and 141%, respectively. Furthermore, the melting temperature and degree of crystallinity increased by 1°C and 16.74%, respectively, along with a noticeable improvement in thermal stability. A micromechanical model is developed, and finite element simulations are conducted to evaluate the effect of hybrid nanofiller addition on mechanical performance. The predicted results showed good agreement with the experimental findings, which validated the model.