Epoxy resin (EP),\u51ed\u501f\u4f18\u5f02\u7684\u7535\u7edd\u7f18\u6027\u3001\u8010\u5316\u5b66\u8150\u8680\u548c\u52a0\u5de5\u5de5\u827a\u7075\u6d3b\u6027\uff0cis widely used in electronic packaging, composite materials, coatings, aerospace, and other fields. However, epoxy resin itself is flammable, with a limiting oxygen index (LOI) of typically only 19%~22%. It is difficult to self-extinguish after exposure to fire, which severely restricts its application in scenarios with high fire safety requirements. Therefore, flame-retardant modification of epoxy resin is highly necessary.
\nAt present, flame retardants for epoxy resin are mainly divided into two categories: additive type and reactive type. Additive flame retardants are physically dispersed in the resin matrix, offering simple operation and low cost, and are currently the mainstream solution for industrialization. Reactive flame retardants are incorporated into the polymer main chain through chemical bonding, providing durable flame-retardant effects without easy migration or leaching, but the process is complex and the cost is higher. Against the backdrop of increasingly stringent environmental regulations, halogen-free formulation has become the core direction of flame-retardant modification of epoxy resin. Among them, phosphorus-nitrogen halogen-free flame retardants,\u51ed\u501f\u9ad8\u6548\u963b\u71c3\u3001\u4f4e\u70df\u4f4e\u6bd2\u3001\u7b26\u5408RoHS\u548cREACH\u6cd5\u89c4\u6807\u51c6\u7b49\u4f18\u52bf\uff0chave become the most widely used flame-retardant solution for epoxy resin. Their flame-retardant mechanism is as follows: upon heating, the phosphorus component promotes polymer dehydration and char formation, forming a dense insulating char layer; the nitrogen component releases inert gases to dilute the concentration of combustible substances, achieving efficient flame retardancy through the phosphorus-nitrogen synergistic effect.<\/p>\n