Theoretical prediction of condensed phase heat of formation of nitramines, nitrate esters, nitroaliphatics and related energetic compounds

Four types of nitrogen-rich heterocycles substituted with -NO2, -NHNO2 and -C(NO2)3 explosophoric groups were explored as potential explosives and propellants materials. The calculated crystal density (?0)and the condensed phase heat of formation (?H?0f)for each of the twelve structures investigated shows that all these derivatives possess high (1.834-1.980 g cm-3)(?H?0f) and (605-2130 kJ kg-1) values. Interesting properties such as detonation velocity (D), pressure (P) and specific impulse (Isp) were calculated using the Kamlet-Jacobs method and ISPBKW thermochemical code. Detonation velocity and pressure in excess of 8.44 km s-1 and 32.87 GPa was obtained in all cases. Furthermore, trinitromethyl substituted derivatives shows performance exceeding that of HMX with an estimated D = 9.32-9.72 km s-1 and P = 40.61-43.82 GPa. Some -NO2 and -NHNO2 substituted derivatives were shown to be impact insensitive while retaining good detonation performance and thus are regarded as potential replacement for current RDX -based explosives. Finally, the calculated specific impulse (Isp between 248 and 270 s) of all investigated derivatives indicate that these energetic materials can be considered as possible ingredient in future rocket propellant compositions.

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Theoretical studies of novel high energy density materials based on oxadiazoles

10.21203/rs.3.rs-234567/v1 ◽

2021 ◽

Author(s):

Wenxin Xia ◽

Renfa Zhang ◽

Xiaosong Xu ◽

Congming Ma ◽

Peng Ma ◽

...

Keyword(s):

Density Functional ◽

High Energy ◽

Heat Of Formation ◽

High Energy Density ◽

Detonation Properties ◽

Detonation Pressure ◽

Energetic Compounds ◽

Functional Theory ◽

High Energy Density Materials ◽

Thermal Stability Of

Abstract In this study, 32 energetic compounds were designed using oxadiazoles (1,2,5-oxadiazole, 1,3,4-oxadiazole) as the parent by inserting different groups as well as changing the bridge between the parent. These compounds had high-density and excellent detonation properties. The electrostatic potentials of the designed compounds were analyzed using density functional theory (DFT). The structure, heat of formation (HOF), density, detonation performances (detonation pressure P , detonation velocity D , detonation heat Q ), and thermal stability of each compound were systematically studied based on molecular dynamics. The results showed that the -N 3 group has the greatest improvement in HOF. For the detonation performances, the directly linked, -N=N-, -NH-NH- were beneficial when used as a bridge between 1,2,5-oxadiazole and 1,3,4-oxadiazole, and it can also be found that bridge changing had little effect on the trend of detonation performance, while energetic groups changing influenced differently. The designed compounds (except for A2 , B2 , B4 ) all had higher detonation properties than TNT, A6 ( D = 9.41 km s -1 , P = 41.86 GPa, Q = 1572.251 cal g -1 ) was the highest, followed D6 had poorer performance ( D = 8.96 km s -1 , P = 37.46 GPa, Q = 1354.51 cal g -1 ).

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Recent Advances in Synthesis and Properties of Nitrated-Pyrazoles Based Energetic Compounds

Molecules ◽

10.3390/molecules25153475 ◽

2020 ◽

Vol 25 (15) ◽

pp. 3475 ◽

Cited By ~ 3

Author(s):

Shijie Zhang ◽

Zhenguo Gao ◽

Di Lan ◽

Qian Jia ◽

Ning Liu ◽

...

Keyword(s):

Energetic Materials ◽

High Performance ◽

High Efficiency ◽

Low Cost ◽

Rapid Development ◽

Development Trend ◽

High Heat ◽

High Energy ◽

Heat Of Formation ◽

Energetic Compounds

Nitrated-pyrazole-based energetic compounds have attracted wide publicity in the field of energetic materials (EMs) due to their high heat of formation, high density, tailored thermal stability, and detonation performance. Many nitrated-pyrazole-based energetic compounds have been developed to meet the increasing demands of high power, low sensitivity, and eco-friendly environment, and they have good applications in explosives, propellants, and pyrotechnics. Continuous and growing efforts have been committed to promote the rapid development of nitrated-pyrazole-based EMs in the last decade, especially through large amounts of Chinese research. Some of the ultimate aims of nitrated-pyrazole-based materials are to develop potential candidates of castable explosives, explore novel insensitive high energy materials, search for low cost synthesis strategies, high efficiency, and green environmental protection, and further widen the applications of EMs. This review article aims to present the recent processes in the synthesis and physical and explosive performances of the nitrated-pyrazole-based Ems, including monopyrazoles with nitro, bispyrazoles with nitro, nitropyrazolo[4,3-c]pyrazoles, and their derivatives, and to comb the development trend of these compounds. This review intends to prompt fresh concepts for designing prominent high-performance nitropyrazole-based EMs.

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