Smart retardant materials for fire alarm systems: integrating flame retardancy and early detection technologies

The increased frequency of fire incidents around the globe has resulted in significant loss of life and property, underscoring the urgent need for advanced fire mitigation strategies. Current approaches largely focus on traditional passive flame retardants and fire alarm sensors. However, flame-retardant additives pose a limited functionality during the intensified fire propagation. Besides, the commercial alarm sensors are generally effective only after significant fire propagation has occurred. Thus, integrating early self-alarm capabilities with flame-retardant properties directly into materials emerges as a highly promising solution. This approach offers rapid-fire detection within a response time of less than 16 s and maintains a stable, effective alarm even under extreme temperatures or during active fires. This review summarizes recent research on smart retardant materials for fire alarm systems (SRM-FASs), which synergistically combine flame retardancy with real-time fire detection to enhance both early warning and sustained resistance. The working mechanism, preparation techniques, and characterization methods of SRM-FASs are discussed. Developing sensitive and reliable SRM-FASs depends on two key aspects: the use of conductive network and flame-retardant materials. The conductive network materials include graphene-based and inorganic-based options, while the flame-retardant aspects specifically refers to biomass materials. Key challenges associated with SRM-FASs are highlighted, and future perspectives and opportunities are proposed. This work aims to provide readers with a comprehensive understanding of SRM-FASs and guide the development of cutting-edge SRM-FASs in the future.