Phosphorus‐Free Flame‐Retardant Strategies for Epoxy Resins

ABSTRACT Driven by the principles of sustainable development and green chemistry, phosphorus‐free flame‐retardant systems have become a key focus in the development of high‐performance polymers because they feature improved ecological safety relative to phosphorus‐based systems. This review focuses on two main phosphorus‐free flame‐retardant strategies: (i) additive phosphorus‐free flame retardants and (ii) intrinsically phosphorus‐free flame‐retardant epoxy resins. Emphasis is placed on the relationship between chemical structure and comprehensive properties, including flame retardancy, thermal properties, and mechanical performance. The flame‐retardant modes‐of‐action for the phosphorus‐free flame‐retardant epoxy systems are also summarized. Finally, current challenges and future development opportunities are presented. This work is expected to facilitate the development of phosphorus‐free flame‐retardant systems.