Superhydrophobic and oleophobic ultra-fine dry chemical agent with higher chemical activity and longer fire-protection

[Display omitted] •The superhydrophobic and oleophobic fire suppressants were successfully fabricated.•MAPP powders have lower Ea and perform higher chemical activities in fire.•The difficulty of being ignited reflects that MAPP can provide a longer protection.•A new strategy for preventing the re-ignition of pool fires was proposed. The re-ignition of pool fires is a common hazard phenomenon in fire extinguishing. Dry chemicals with oleophobicity may solve this problem because powders can float on the oil surface and prevent evaporation of fuel pool. In this research, MAPP (modified ammonium polyphosphate) with superhydrophobicity, oleophobicity, and higher chemical activity is prepared which can quickly quench pool fires and provide longer protection. The activation indexes of MAPP for water, diesel, aviation kerosene and gasoline are 98.5%, 87.4%, 98.7% and 98.4%, respectively. Lower activation energy of MAPP means that it will show higher chemical activity in fire. The fire-extinguishing performance of MAPP is much higher than that of Commercial UDCA (ultra-fine dry chemical agent) during fire experiments. After extinguished by MAPP, the fuel pool is hard to be re-ignited. The significance of this study is to propose a new strategy for preventing the re-ignition of pool fires.