Flame retardants are chemical compounds when mixed or incorporated in to polymers provide varying degrees of flammability protection. Flammable polymeric materials are ubiquitous with a wide array of applications. However, recent studies have shown potential environmental and health concerns with certain halogen-containing flame retardants. Thus, it has now become a necessity to explore new and effective materials that are safer and environmentally benign. In this context, halogen-free phosphorus- and nitrogen-containing flame retardants have attracted much attention worldwide. Moreover, s-triazine is the central focus because of its excellent charring effect. General strategies for synthesizing s-triazine compounds mostly via nucleophilic substitution reaction have been highlighted. This review provides a comprehensive description on design and synthesis of flame-retardant materials with significant flammability performance.
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