Properties and applications of novel composite foam for blocking air leakage in coal mine

A novel composite foam material for blocking air leakage in coal mine was developed. In order to examine the performance of the new composite foam, the foaming property, mechanical property, microstructure, thermal stability, and flame resistance of the composite foams, polyurethane foams, phenolic foams, and urea-formaldehyde foams were investigated. The results show that the composite foam had the biggest compressive strength, thermal stability, and flame resistance. Moreover, composite foam had the lowest foaming temperature and shrinkage, indicating that it had small risk in causing spontaneous combustion of coal, and it exhibited good air leakage blocking effect. Field application showed that composite foam could effectively block air leakage in goaf. Thus, composite foam materials were considered to be the potential candidates for blocking air leakage in coal mines to prevent spontaneous combustion of coal.