Experimental research on temporary closed wall constructed by graphene polyurethanen in coal mine

In order to address problems of heavy materials and inefficient construction of traditional mine ventilation structuresꎬ a new type of graphene polyurethane foam was developed and its performance for various structures was tested. Firstlyꎬ new graphene polyurethane foam was prepared using one ̄step method. Thenꎬ its hermeticity was tested through gas permeability experiments of plastic films and sheets. Finallyꎬ its structures were analyzed by using a comprehensive thermal analyzerꎬ a Fourier transform infrared spectrometer and a metallographic microscope. The results show that the density of new graphene polyurethane foam is only 40 kg / m . Infrared spectrum shows that it is rich in organic functional groups such as C = Cꎬ C = Oꎬ ̄OHꎬ ̄CO and ̄NHꎬ and based on observation of metallurgical microscopeꎬ distribution of 160 μm foam is uniform and stable. And the new material remains highly efficient and hermetic within 30 days of simulation testꎬ maintains excellent thermal stability within 400 °Cꎬ and can 中 国 安 全 科 学 学 报 China Safety Science Journal 第30卷 2020年 extinguish within 0􀆰 13 s from fireꎬ thus reducing fire risks during its use as a temporary ventilation structure in the mine.