氮氧化-1,2,3-三唑含能离子盐的设计合成与性能研究

Functionalization of nitrogen-rich heterocyclic frameworks is one of the most efficient strategies for fine-tuning the relationship between energy and sensitivity of energetic materials at a molecular level. Essentially, 1,2,3-triazole frameworks possess some intrinsic properties including positive enthalpy of formation, high nitrogen content, and good thermal stability, etc., which makes them a promising class of starting building skeletons for constructing new high energy density materials. Around such considerations, this project aimed to design a series of novel energetic 1,2,3-triazole-derived salts with adjustable energy and sensitivity via the strategies of N-oxidation, ionization, by the aid of energy pre-evaluation of computer calculation. Considering the difficulty in constructing these complex 1,2,3-triazole frameworks, different synthetic routes have been designed to achieve their reliable syntheses according to molecular structure, in which condition optimizations for key reactions will be conducted. In addition, studies on their energy, safety and stability properties, the high-throughput screening of new energetic molecules with high energy and low sensitivity will be achieved, meanwhile having a deeper insight into the relationships between their structure and properties. The successful implementation of this project can not only promote the R&D of 1,2,3-triazole-derived energetic materials but also provide theoretical and experimental basis for exploring more new energetic compounds with similar structures.

富氮杂环骨架的官能化是从分子水平上协调含能材料能量与感度有效策略之一。鉴于1,2,3-三唑骨架较正的生成焓、高氮含量和良好的热稳定性，本项目采用氮氧化、离子化等两种策略对该类骨架能量与安全性进行可控调节，并结合计算模拟对分子能量的预估，设计一系列结构新颖的氮氧化-1,2,3-三唑含能离子盐；拟通过对不同结构特点氮氧化-1,2,3-三唑骨架分子的合成路线设计、关键合成步骤条件优化等研究实现含能离子盐的可靠制备；进一步开展相应离子盐能量、安全与稳定性等相关性能的研究，以实现性能优异含能化合物的高通量筛选，同时深入掌握氮氧化-1,2,3-三唑骨架的能量与安全特性。本项目的顺利开展，不仅可推动三唑类含能离子盐的研究与发展，而且可为基于该类骨架的新型含能分子的设计提供理论与实验依据。

富氮杂环骨架的功能化是从分子水平上协调含能材料能量与感度有效策略之一，通过该策略有望实现具有应用前景的新型炸药分子的合成。本项目通过在1,2,3-三唑、1,2,4-三唑等氮杂环骨架之上，通过其环上氮杂原子之上发展氮氧化、氮硝胺化、氮偕二硝甲基化等三种氮功能化策略，并合成系列离子盐进一步调节目标分子的能量与安全性，进而研究其爆轰与安全性参数。本项目合成了20余新型的含能分子，并通过核磁、红外、元素分析、单晶等手段完成了这些分子的结构表征；研究了这些化合物的热分解温度、撞击感度、摩擦感度等安全性能；研究了这些化合物的生成焓、爆速、爆压等爆轰参数。氮氧化-1,2,3-三唑分子的设计与爆轰参数的计算表明该类分子的平均爆速在9000 ms-1左右，揭示了该类分子良好的爆轰性能。通过合成获得了热分解温度高达399 oC的耐热型炸药分子；通过稠环骨架的氮硝胺化反应的探索，获得了实测密度1.946 g cm-3，计算爆速、爆压分别为9427 ms-1和41.9 Gpa，能量水平超过了HMX的新型的高能炸药分子；通过二呋咱吡嗪的氮硝胺化反应研究和相应含能离子盐的合成与性能研究，获得了爆速、爆压（9166 ms-1、31.4 Gpa）与RDX相当，撞击感度（8 J）亦与RDX相当的新型高能低感炸药分子；通过DNBT的氮偕二硝甲基化反应及相应含能离子盐的合成与爆轰参数研究，不仅获得了实测密度1.954 g cm-3，计算爆速、爆压分别为9394 ms-1和39.7 Gpa的新型高能炸药分子，而且获得了实测密度1.856 g cm-3，计算爆速、爆压分别为9166 ms-1和36.9 Gpa，撞击感度和摩擦感度分别为15 J和240 N，能量与安全性均优于RDX高能低感含能离子盐。通过三种氮功能化策略的研究，不仅获得了新型的高能炸药分子，而且为其他杂环骨架的功能化获得性能优良的新型炸药提供了新的思路。