Preparation of Polyoxymethylene/Exfoliated Molybdenum Disulfide Nanocomposite through Solid-State Shear Milling

In this paper, the solid-state shear milling (S³M) strategy featuring a very strong three-dimensional shear stress field was adopted to prepare the high-performance polyoxymethylene (POM)/molybdenum disulfide (MoS₂) functional nanocomposite. The transmission electron microscope and Raman measurement results confirmed that the bulk MoS₂ particle was successfully exfoliated into few-layer MoS₂ nanoplatelets by the above simple S³M physical method. The polarized optical microscope (PLM) observation indicated the pan-milled nanoscale MoS₂ particles presented a better dispersion performance in the POM matrix. The results of the tribological test indicated that the incorporation of MoS₂ could substantially improve the wear resistance performance of POM. Moreover, the pan-milled exfoliated MoS₂ nanosheets could further substantially decrease the friction coefficient of POM. Scanning electron microscope observations on the worn scar revealed the tribological mechanism of the POM/MoS₂ nanocomposite prepared by solid-state shear milling. The tensile test results showed that the pan-milled POM/MoS₂ nanocomposite has much higher elongation at break than the conventionally melt-compounded material. The solid-state shear milling strategy shows a promising prospect in the preparation of functional nanocomposite with excellent comprehensive performance at a large scale.