Highly stable poly-nitro components achieved through supramolecular encapsulation

Abstract

As representatives of poly-nitro oxidant components, dinitramide [⁻N(NO₂)₂, DN] and nitroformate [⁻C(NO₂)₃, NF] exhibit a very large potential as energetic materials given their highly available oxygen content. However, their low thermal stabilities have always been the main reason limiting their applications. Now, a strategy of encapsulating poly-nitro components through supramolecular self-assembly has been developed; six supramolecular encapsulated structures (two series): MA@DN, MA@NF, MA@TNP; TATOT@DN, TATOT@NF, and TATOT@TNP (Ma: melamine; TATOT: 3,6,7-triamino-7H-[1,2,4]triazolo[5,1-c][1,2,4]-triazole; TNP: 3,4,5-trinitro-pyrazolate) were assembled simply in aqueous solution. Benefiting from the supramolecular structure, and the fixed hydrogen bonds formed between the poly-nitro components and the supramolecular framework, the thermal stability of these poly-nitro components was improved remarkably. Particularly, the decomposition temperatures of MA@DN, MA@NF, and MA@TNP are 243, 225, and 268 °C, respectively, which are the highest decomposition temperatures among these derivatives. Additionally, supramolecules based on TATOT exhibit excellent detonation properties and lower sensitivities to mechanical stimuli, which makes them promising as high energy materials with lower sensitivities. This work provides a new strategy for stabilizing liable components, and as a result, more and more highly energetic and stable materials based on poly-nitro components will be prepared.