Functional MXene-Based EP Nanocomposites with Integrating Mechanical Toughness, Robust Adhesion, and Superior Fire Retardancy

The excellent adhesion and chemical corrosion resistance of epoxy resin (EP) are widely used in the field of materials. However, the problems of its flammability and mechanical loss after modification urgently need to be solved. Here, the D@M nanosheets prepared by coating the surface of MXene with DHPPC allow the EP to achieve the effects of both fire safety and mechanical enhancement. The EP nanocomposites can reach the V-0 level at 1 wt % addition, the oxygen index is as high as 29.8%, and the charring is rapid and dense. The peak heat release rate (pHRR), CO, and CO₂ production rate values are reduced by 31.20, 45.41, and 37.57%, respectively. The fire and smoke suppression effect is excellent. In addition, the mechanical properties of EP nanocomposites were enhanced due to the uniform dispersion of nanosheets and the two-dimensional structure of the nanosheets. The tensile strength and flexural strength were, respectively, increased by 32.9 and 12.4% with the addition of 1.5 wt %. The polymer coated on the surface of the nanosheet increases the viscosity of the nanocomposite itself and shows good adhesion in the face of different common plates. The bonding strength of the steel can even reach 13.53 MPa. It provides an efficient and practical solution for the realization of multifunctional EP nanocomposites with mechanical enhancement, fire safety, and strong bonding.