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为了研究晶体形态对炸药物化性能、应用方式和应用效果的影响,采用溶剂‑非溶剂结晶法,分别以二甲亚砜(DMSO)为溶剂、乙酸乙酯为非溶剂、1‑乙基‑3‑甲基咪唑乙酸盐(EmimOAc)为结晶助剂,制备得到花球状2,6‑二氨基‑3,5‑二硝基吡嗪‑1‑氧化物(LLM‑105)晶体。EmimOAc的添加显著增强了LLM‑105在DMSO中的溶解度,改变了LLM‑105晶体生长方式和结构形态,对晶型无影响。热分析测试结果表明:花球状LLM‑105晶体有两个明显的分解峰温,分别为347.3~350.5 ℃和356.7~360.4 ℃。采用GJB‑772A-1997方法601.2测试了花球状LLM‑105晶体的撞击感度,采用冲击片雷管起爆测试方法测试了花球状LLM‑105晶体的冲击片起爆感度,结果表明:花球状LLM‑105晶体的撞击感度与亚微米晶体相当,显著低于针状晶体;冲击片起爆电压低于亚微米晶体。“,”The crystal habit of explosives significantly affects their physicochemical properties, application mode and effect. A novel strategy to fabricate the flower spherical 2,6‑diamino‑3,5‑dinitropyrazine‑1‑oxide (LLM‑105) crystals based on solvent‑antisolvent method was developed by introducing 1‑ethyl‑3‑methylimidazole acetate (EmimOAc) ionic liquid as the additives, DMSO as the solvent and ethyl acetate as the antisolvent. The results show that the EmimOAc ionic liquid is a crucial factor to modify the crystal morphology of LLM‑105. Long needle‑like LLM‑105 crystals were produced in the absence of EmimOAc. In contrast, flower spherical LLM‑105 crystals were obtained in the presence of EmimOAc. In addition, the EmimOAc significantly enhanced the solubility of LLM‑105 in DMSO. Meanwhile, 1H NMR experiments were conducted to understand the intermolecular hydrogen bonds between LLM‑105 and the ionic liquid molecules. Furthermore, the flower spherical LLM‑105 crystals exhibit excellent thermal stability and safety properties. The DSC/TG results show that the thermal stability of the flower spherical crystals is comparable to that of the long needle crystals. The impact sensitivity was tested according to GJB‑772A-1997 method, while the impulse initiation voltage was tested by slapper detonator. Results indicate that for the flower spherical crystal, the characteristic drop height is 22 cm higher than that of the needle crystal, and the impact sensitivity is significantly lower than that of the needle crystal but equivalent to that of the submicron crystal. The impulse initiation voltage of the flower spherical crystals is lower than that of submicron crystals, suggesting that the flower spherical crystals have better initiation performance and high potential for application in primary explosives. This ionic liquid induced crystallization provides a new idea for tuning the crystal habit of LLM‑105, as well as a new method for modifying the crystal habits of other organic explosive crystals.