Solid Fire Suppression Performance and Mechanism of a Novel Environmental-Friendly Hydrogel

ABSTRACTThe types of solid fires are diverse and the suppression highly depends on the adhesion and surface cooling effects of the extinguishing agent. In order to overcome the disadvantage of low adhesion and improve the efficiency of water in suppressing fires, a novel environmental-friendly thermal gelation hydrogel was prepared with hydroxypropyl methylcellulose (HPMC), sodium n-dodecyl sulfate (SDS), and super absorption resin (SAR) as the main raw materials. Ammonium polyphosphate (APP) and aluminum hydroxide (ATH) were added to enhance the fire-suppressive properties of the hydrogel. Then, cone calorimetry experiments were carried out to investigate the suppression effects differences between the hydrogels and water. According to response surface methodology, the optimal composition of hydrogel is the amount of HPMC, SDS, and SAR was 1.28 wt%, 1.50 mM, and 0.20 wt%, respectively. By adding APP and ATH flame retardants in combination, the hydrogel exhibited a reduced gelation temperature and an improvement in viscoelasticity, making it more effective in suppressing fires. Compared with water, solid fuel samples covered with hydrogel presented longer time to ignition. The maximum heat release rate was reduced by 53.27 kW/m2 and total smoke production exhibited a reduction of 12.23%. The hydrogel generated a fireproof and dense char layer on the solid surface, which acted as a barrier against heat and mass exchange, effectively suppressing the development of fire. The results of this study can provide guidance for the development of hydrogel extinguishing agents.KEYWORDS: Fire suppressingcombustion performancethermal gelation hydrogelgelling performance AcknowledgementsThis work was supported by the National Natural Science Foundation of China (grant number 52174206), the Youth Innovation Team Project of Higher School in Shaanxi Province (grant number 22JP047), and the Shaanxi Key Science and Technology Innovation Team Project (grant number 2023-CX-TD-42).Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by Li Ma [52174206 and 2023-CX-TD-42]; Gaoming Wei [22JP047].