Preparation and Performance Analysis of Flame Retardant Microcapsules TP-MF-SPI for Inhibiting Spontaneous Combustion Tendency of Coal

In order to solve the problem of coal mine fires caused by spontaneous combustion of coal, which often occurs during coal production, a new type of tea polyphenol-melamine formaldehyde resin-soy protein isolate (TP-MF-SPI) flame-retardant microcapsule was prepared by in situ polymerization in this paper. This is a flame-retardant microcapsule with tea polyphenol (TP) and MgCl2 as the core material and soy protein isolate (SPI)-modified diamine resin as the wall material. When the coal samples were oxidized and decomposed rapidly due to the temperature increase and slowly entered into the combustion stage, the coal samples with added core and microencapsulated materials have increased several important temperature points compared with the original coal. From the simultaneous thermal analyzer experiments, it was concluded that the temperature point of the mass maxima by 1.3℃ and 4.7℃, the ignition temperatures by 1.6℃ and 4.1℃, and the temperature point of the maximal loss rate by 3.7℃ and 12.3℃. It can be seen that the use of microencapsulation technology for magnesium chloride-tea polyphenol coating can be more effective in prolonging the flame-retardant life of the core material in the high temperature stage of the coal samples, and to enhance its flame-retardant effects. The performance test of microencapsulated flame retardant using cone calorimeter experiment and thermal stability analysis experiment showed that the peak heat release rate of the original coal samples and the coal samples with 1:5, 1:4, 1:3 flame retardant additions were 72.54 kW/m2, 55.17 kW/m2, 35.99 kW/m2, 30.31 kW/m2. Through the different ratios of microcapsule material coal samples show the effect of flame retardant effect and the cost of a comprehensive comparison and analysis, to determine the 1:4 microcapsule material additive amount can play the best flame retardant effect on the coal sample.