A review: synthesis, application and modification research progress of melamine–formaldehyde resin

Abstract Melamine–formaldehyde (MF) resin, a thermosetting polymer synthesized through the condensation reaction of melamine and formaldehyde, has gained significant applications and research interest owing to its unique properties. This review systematically introduces the synthesis, application and modification progresses of MF resin. The effects of raw material ratios and reaction conditions on the chemical structure and properties of MF resin are discussed. Recently developed MF resin has specialized performances for applications such as wood impregnation, coatings, adhesives and flame retardants. Additionally, MF foam exhibits microstructural and macroscopic functional properties, especially for applications in thermal insulation, sound absorption and oil–water separation. Addressing inherent limitations such as brittleness and free formaldehyde release, this paper comprehensively reviews modification approaches including chemical modifications, physical blending and composite modification techniques, along with their effectiveness in enhancing MF resin toughness. This paper provides systematic theoretical knowledge and practical guidance for improving MF resin performance, expanding application scopes and driving innovative development to meet evolving industrial demands and technological challenges. © 2025 Society of Chemical Industry.