Epoxy composites with functionalized molybdenum disulfide nanoplatelet additives

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Molybdenum disulfide (MoS₂) is a 2D material analogous to graphene, noted for its unique nanostructure and properties.
• Interfacial interactions are crucial for improving thermal and mechanical characteristics in polymer/inorganic nanosheet composites.

Purpose of the Study:

• To investigate the effectiveness of functionalized MoS₂ nanosheets as reinforcing additives in epoxy polymers.
• To evaluate the impact of functionalized MoS₂ on the mechanical and thermal properties of epoxy composites.

Main Methods:

• Exfoliation of bulk MoS₂ into nanosheets.
• Functionalization of MoS₂ nanosheets using 3-mercaptopropyltriethoxysilane (f-MoS₂).
• Dispersion of f-MoS₂ in epoxy using ultrasonication and three-roll mills at low loading fractions (0.1-0.7% by weight).

Main Results:

• Functionalized MoS₂ (f-MoS₂) nanoplatelets significantly enhance tensile, fracture, and adhesive properties of epoxy composites.
• Low nanofiller loading fractions (0.1-0.7% by weight) of f-MoS₂ lead to substantial improvements.
• Glass transition temperature increased from 135 °C (unfilled epoxy) to 146 °C at 0.7% f-MoS₂ loading.
• Apparent shear strength at 120 °C increased from 13.8 MPa (unfilled epoxy) to 24.9 MPa at 0.7% f-MoS₂ loading.

Conclusions:

• Functionalized 2D sheets of transition metal dichalcogenides, like MoS₂, are effective reinforcing additives for polymeric composites.
• The study demonstrates the potential of f-MoS₂ in enhancing the performance of epoxy-based materials at very low concentrations.