Study on flame retardancy and mechanical properties of paraffin/stearic acid-based composite for preventing coal spontaneous combustion

To make paraffin as the inhibitor for the secundine ball shell material better apply in the field of coal mine fire prevention, the melting system with the ratio of paraffin to stearic acid 4:1 was used as the matrix material, three materials with different mass percentages were chosen as additives. The influence of samples on the flame-retardant performance and stability of the matrix material was examined using cone calorimetry and thermogravimetric analysis, then combined with material mechanics performance to determine the best proportion composite. The results show that the flame retardancy of the matrix is improved by adding three kinds of materials, but the stability of chlorinated paraffin is poor; and when the mass percentage of Zn 3 B 6 O 12 ·3.5H 2 O and Al (OH) 3 is 15%, the flame retardancy and mechanical properties of the composite are significantly improved: the flame performance index increased from 0.012 to 0.193 m 2 s kW −1 , and the maximum stress increased from 1.776 to 4.578 Mpa. Besides, the presence of composite materials reduces the amount of CO generated during the low-temperature oxidation of coal before 180 °C, indicating that it has a certain inhibitory effect on the low-temperature oxidation process of coal.