Synthesis and Characterization of Pressure Resistant Agent with Double‐Layer Core/Shell Hollow‐Structure for Emulsion Explosive

Abstract

A novel pressure resistant agent (PRA) for emulsion explosive was prepared by a high-speed shear mixer with cenospheres, Al 2 (SO 4 ) 3 , NaHCO 3 and hydrophobic nano-silica as the raw materials. The structural features of the PRAs were characterized using a scanning electron microscope, a laser particle size analyzer and an optical microscope, and the experimental results showed that the PRAs were ellipsoidal microspheres with an average particle size of 200 μm and had double-layer core/shell hollow-structures. The inner hollow shell of the microsphere could serve as sensitizing bubble when it was undamaged whatever the status of outer shell, and once it was broken, the materials in the outer and inner shells would react with each other and generate new sensitizing bubbles in emulsion explosive. The brisance and underwater explosion experimental results showed that when the addition of PRAs was determined to be 2 mass %, the resistance to dynamic pressure of emulsion explosive sensitized by glass microsphere (GM) would be improved significantly without affecting its power. The lead column compression of GM-2 mass % PRAs sensitized emulsion explosive was 16.05 mm, which was close to that of GM sensitized emulsion explosive. When compressed by a RDX booster underwater at the distances of 25 and 75 cm, the dynamic pressure resistance ability of GM-2 mass % PRAs sensitized emulsion explosive would increase by 56.54 and 62.07 %, respectively, compared to that of GM sensitized emulsion explosive at the same compression distance. This novel PRA provided double protections for improving the pressure resistant properties of emulsion explosives, especially in the condition of dynamic pressure compression.

Effect of Perlite Content on Performance of Emulsion Explosive in Under-Water Environment

“…It has been more than 50 years since the development of the emulsion explosive, which is an oil-inwater emulsion system formed by a dispersed phase and a continuous phase [1] . Emulsified explosives take into account the characteristics of nitroglycerin and ammonium nitrate explosives, which not only ensure explosive performance but also has good safety [2,3] .…”

Experimental Study on Emulsion Explosive Blasting under Different Under-Water Pressure

“…Underwater blasting construction has always been an important means of coastal engineering construction [1][2]. In underwater blasting construction engineering, emulsified explosive is widely used because of its good waterproof performance and low cost [3][4]. In an underwater explosion, explosives will release a large amount of chemical energy, resulting in high-speed expansion of high-temperature and high-pressure gas.…”