Carbon nitride/polyaniline/metal oxide composite system endows epoxy resin with reinforcements in the fire safety, thermal stability, and water resistance

Reducing the fire risk of epoxy coatings has been a significant focus in the research of thermosetting resin materials. Various carbon nitride/polyaniline/metal oxide hybrids (CNPMOs) were synthesized using in‐situ oxidative polymerization and modified adsorption methods. Combustion analysis results indicated that CNPMOs effectively reduced the heat release of epoxy coatings during combustion. The epoxy coatings containing various CNPMOs (EFe, EY, and ETi) exhibited excellent smoke suppression and toxicity reduction properties. Furthermore, in comparison to the pure sample (E0) and reference sample (E1), the epoxy coatings EFe, EY, and ETi demonstrated improved thermal stability. In water resistance tests, the water absorption rates of EFe, EY, and ETi were significantly lower than that of E0. The CNPMOs enhanced the hydrophobicity of the epoxy coating to better protect the substrate in humid environments. Carbon nitride/polyaniline/metal oxide hybrids (CNPMOs) can effectively enhance the fire safety, thermal stability, and water resistance of epoxy resin coatings.