Propyl nitroguanidine (PrNQ) is an important nitroguanidine (NQ) derivative and is considered to be promising as a melt-cast carrier explosive (melting point: 98–99 ​°C) due to its low cost, low sensitivity, and good compatibility. However, the effects of alkyl chains on the physicochemical properties of nitroguanidine derivatives have not been well established. In this work, we investigated the physicochemical properties of three structurally similar nitroguanidine derivatives in detail, namely, propyl nitroguanidine (PrNQ), propargyl nitroguanidine (PraNQ), and isopropyl nitroguanidine (IPrNQ). These different three-carbon alkyl group substituents cause these nitroguanidine derivatives to form different crystal structures and intermolecular interactions (hydrogen bonds and van der Waals interactions), which in turn result in significantly different densities, melting points, decomposition temperatures, and detonation properties. These results demonstrate the important influence of the alkyl chain on the physicochemical properties of nitroguanidine derivatives and provide guidance for designing new alkyl-substituted energetic materials, especially for melt-cast explosives.

丙基硝基胍（PrNQ）是重要的硝基胍（NQ）衍生物，由于其低成本，低灵敏度和良好的相容性，被认为是有前途的熔融铸造载体炸药（熔点：98-99°C）。但是，烷基链对硝基胍衍生物的理化性质的影响尚未得到很好的确定。在这项工作中，我们详细研究了三种结构相似的硝基胍衍生物，即丙基硝基胍（PrNQ），炔丙基硝基胍（PraNQ）和异丙基硝基胍（IPrNQ）的理化性质。这些不同的三碳烷基取代基使这些硝基胍衍生物形成不同的晶体结构和分子间相互作用（氢键和范德华相互作用），反过来会导致密度，熔点，分解温度和爆炸特性发生显着不同。这些结果证明了烷基链对硝基胍衍生物的理化性质的重要影响，并为设计新的烷基取代的高能材料，特别是熔铸炸药提供了指导。