Functionalized epoxy resins for enhanced interface properties and corrosion resistance: Tailoring of surface and interface properties and performance

The use of functionalized epoxy resins (FERs) to improve corrosion resistance in various industrial applications has grown. Covalent and noncovalent modifications are the two main techniques for functionalizing epoxy resins. The addition of hydroxyl (‒OH), amino (‒NH₂), or carboxyl (‒COOH) groups through covalent functionalization to the ERs enhances their reactivity, adhesion, and solubility of epoxy resins. Noncovalent functionalization entails adding nanomaterials such as metals, metal oxides, and carbon allotropes to the resin matrix. Functionalized ERs are more effective anti-corrosive materials in the aqueous phase and the coating. Growing solubility and more polar functional groups are responsible for FERs' improved potential to guard against corrosion in the aqueous phase. Mechanical strength, chemical and thermal stability, and corrosion resistance are traits that these alterations improve. Significant improvements in corrosion resistance have been demonstrated when epoxy resin coatings with inorganic (TiO₂, CeO₂, SiO₂, Al₂O₃, h-BN, lanthanides, etc.) and organic (G, GO, CNTs, PANI, MXenes, MOFs, PDA, BIM, LDH, polymers, etc.) additives are used. The curing agents greatly influence the efficiency of the functionalized epoxy resins. The curing environment and agent type directly affect the resin's mechanical, thermal, and chemical properties. The adhesion qualities of epoxy resins can be significantly improved by functionalized curing agents, such as those treated with silane. The present article describes the corrosion protection behavior of FERs in aqueous and coating phases and their current challenges and opportunities.