Preparation and performance study of low heat storage flame retardant polyurethane for coal mines

In order to meet the requirements for the use of polyurethane for reinforcement in mines, the synthesis temperature of polyurethane needs to be lowered, and the flame-retardant and mechanical properties of polyurethane should also be considered comprehensively. Factors affecting the synthesis temperature of polyurethanes are investigated, low heat storage polyurethanes that meet the temperature requirements for use in plugging crushed coal bodies in coal mines are formulated, and the synthesized polyurethanes are characterised for their flame retardant properties by FTIR, SEM, TG-FTIR and CONE experiments. It was found that in this paper, a new type of polyurethane for coal mines was formed by flame retardant modification of polyurethane by adding nano-system flame retardant and phosphorus-system flame retardant, and the synthetic reaction temperature of the material could reach as low as 51.2 °C, and the pyrolysis onset temperature was increased to 286 °C. The experimental results show that the flame retardant property of this synthetic polyurethane has been significantly improved, and the heat accumulation effect of the synthesis process on the surrounding coal body has been greatly reduced. The physical properties and thermal stability of this synthetic polyurethane in the grouting process meet the safety requirements for use in underground coal mines.