ABSTRACT Confined‐space electrical fires present significant hazards, primarily stemming from the inherent limitations of conventional fire‐extinguishing agents. To address this challenge, thermosensitive microencapsulated cis‐hexafluoro‐2‐butene (HFO‐1336mzz(Z)) fire extinguishing agents were synthesized via microfluidic technology, using melamine resin as the shell material and HFO‐1336mzz(Z) as the composite core. The microcapsules featured uniform particle size and smooth, dense surfaces morphologies. Furthermore, the release behavior and fire extinguishing efficiency of the microcapsules were systematically analyzed. Key findings are summarized as follows: The pyrolysis of the microcapsules proceeds through four distinct stages: moisture evaporation, core material volatilization, shell rupture, and wall decomposition. The release temperature and rupture temperature of the microcapsules were determined to be 95.5°C (with a cumulative release rate of 15.49%) and 108.5°C (with a cumulative release rate of 98.62%), respectively. Release kinetics fitting demonstrated that the zero‐order model best described the release behavior at 95.5°C ( R 2 = 0.9884), indicating a constant‐rate diffusion mechanism. At 108.5°C, the release process conformed to the Higuchi model ( R 2 = 0.9176), confirming a diffusion‐dominated mechanism. In confined‐space fire extinguishing tests, the deployment of the microcapsules reduced combustion time to 36 s, constrained the peak temperature to 143.3°C, and rapidly lowered oxygen concentration to 6.9% within the 35–38 s timeframe. Notably, significant transformation of flame morphology was observed after 10 s of combustion, accompanied by the rapid formation of a yellowish moderate‐temperature zone. This study provides an eco‐friendly and efficient alternative for suppressing confined‐space electrical fires, overcoming the limitations of conventional fire‐extinguishing agents.
Kang et al. (Thu,) studied this question.