Propellants Explosives Pyrotechnics, Vol.45, No.6, 932-941, 2020
Fabrication and Characterization of a Novel Underground Mining Emulsion Explosive Containing Thickening Microcapsules
In order to solve the sloughing problem of explosives in upward blast holes, a novel underground mining emulsion explosive with thickening microcapsules was developed. The microcapsules in the emulsion explosive would be damaged by high-speed shearing at the moment of entering the blast hole, releasing their internal thickening agents to the emulsion explosive in the blast holes. These thickening agents were evenly distributed with a linear network structure in the emulsion explosive to make it thickened in the hole. The microcapsules were spherical and could encapsulate the thickening agent effectively, and the viscosity of the emulsion matrix with 2 mass % of them was close to that of the reference emulsion matrix at ca. 127.9 Pa s. Experimental results of TG-DSC and detonation performance showed that the novel underground mining emulsion explosive had a good thermal stability and its detonation velocity was 5133 m s(-1) and still up to 4618 m s(-1) after storing at the temperature of -20 degrees C for 12 h. The novel underground mining emulsion explosive with thickening microcapsules not only achieved the goal of thickening in the blast holes, but also had excellent detonation performance and low-temperature resistance capability.