Enhancing Polymer‐Based Composite Properties via the Mechanical Chain Effect of Amino‐Functionalized Molybdenum Disulfide Nanosheets

ABSTRACT Over the past few decades, the optimization of polymer properties through the design of functionalized MoS ₂ has attracted increasing attention owing to the excellent properties of two‐dimensional fillers at the nanoscale. These fillers offer inherent advantages in terms of stiffness, strength, and toughness. This study investigates a facile process to synthesize amino‐functionalized MoS ₂ for enhancing the mechanical properties of epoxy resins (EPs). We used 4,4′‐diaminodiphenyl sulfone (DDS) as a modifier to synthesize DDS‐MoS ₂ nanosheets via high‐frequency liquid‐phase ultrasonication, obtaining nanosheets with an average longitudinal size of 1–2 nm. Raman spectroscopy confirmed that the DDS‐functionalized nanosheets had greater structural disorder and improved dispersion within the matrix. The amino groups on the nanosheet surface formed bonds with the epoxy groups, preventing MoS ₂ accumulation. Compared with pure EP and MoS ₂ /EP composites, the DDS‐MoS ₂ /EP demonstrated substantially improved thermal stability and mechanical properties and exhibited 11.1% and 42.4% higher tensile modulus and strength, respectively. Moreover, its impact strength was increased by 208.5%. Dynamic mechanical analysis revealed an increase of 31.6°C in the glass‐transition temperature ( T _g ) and an improvement in the storage modulus. These enhancements are attributed to the improved dispersion and compatibility between the nanosheets and resin matrix, facilitated by the DDS‐based modification.