Array-structured microcapsule fibers for efficient fire extinguishing in confined spaces

Fire incidents in confined spaces pose significant risks to human lives and property. In such scenarios, achieving structural encapsulation and design of fire extinguishing agents is crucial. However, there is still a significant knowledge gap in the rational structural design and understanding of fire extinguishing mechanisms. Herein, we have developed a fire extinguishing material with a hemispherical knotted microfiber structure by microfluidic spinning and achieved directed multiple-fire extinguishing in a confined space. Fire-extinguishing microfibers (FEMFs) are uniformly distributed with perfluorohexanone (PFH)-embedded knots, each of which acts as an independent fire-extinguishing unit. The rational design of fiber microstructure can achieve a variety of dosage ratios of extinguishing agents that activate at a fire extinguishing temperature of 120 °C. Through high-speed imaging and simulation calculations, we found that FEMFs containing only 0.2 g PFH can generate up to 207 directional jets to extinguish fires. Fire-extinguishing patches (FEPs) made from FEMFs have a uniform distribution of the extinguishing agent and exhibit excellent fire extinguishing performance in electrical junction boxes. This new fire extinguishing material is believed to have broad applications in enhancing fire safety within confined spaces.