Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involv...Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive performance.Utilizing this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic compounds.Notably,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),respectively.Additionally,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and stability.This work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.展开更多
Two new cage compounds,4-trinitroethyl-10-nitro-2,6,8,12-tetraacetylhexaazaisowurtzitane（3） and 4-trinitroethyl- 2,6,8,10,12-pentanitrohexaazaisowurtzitane（4）,containing trinitromethyl group were synthesized by a ...Two new cage compounds,4-trinitroethyl-10-nitro-2,6,8,12-tetraacetylhexaazaisowurtzitane（3） and 4-trinitroethyl- 2,6,8,10,12-pentanitrohexaazaisowurtzitane（4）,containing trinitromethyl group were synthesized by a novel method,and their structures were confirmed by IR,;H NMR,MS and single crystal X-ray.DSC result shows that compound 4 has surprising thermal stability and could be a potential energetic compound.展开更多
Two general expressions and their six derived formulae for estimating the critical temperature（Tb） of thermal explosion for energetic materials（EMs） were derived from the Semenov＇s thermal explosion theory and ei...Two general expressions and their six derived formulae for estimating the critical temperature（Tb） of thermal explosion for energetic materials（EMs） were derived from the Semenov＇s thermal explosion theory and eight non-isothermal kinetic equations via reasonable hypothesis. We can easily obtain the values of the initial temperature（T0i） at which DSC curve deviates from the baseline of the non-isothermal DSC curve of EMs, the onset temperature（Tei）, the exothermic decomposition reaction kinetic parameters and the values of Too and Te0 from the equation Toiorei=Tooore0＋α1β1＋α2β2＋...＋αL-2βi^L-2, i=1, 2, …, L and then calculate the values of Tb by means of the six derived formulae. The results obtained with the six derived calculating methods for six trinitromethyl explosives： bis（2,2,2- trinitroethyl-N-nitro） ethylene diamine（BTNEDA）, 2,2,2-trinitroethyl-4,4,4-trinitrobutyrate（TNETB）, bis（2,2,2- trinitroethyl） formal（BNTF）, bis（2,2,2-trinitroethyl-nitramine）（BTNNA）, 2,2,2-trinitroethyl-2,2,2-trinitroethyl-N- nitroamino acetate（TNTNNA） and tetrakis [2,2,2-trinitroethyl] orthoester（TTNOE） agree well with each other.展开更多
基金supported by the National Natural Science Foundation of China(No.22375021,22235003,22261132516&22205021)the BIT Research and Innovation 265 Promoting Project(Grant No.2023YCXZ017)。
文摘Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive performance.Utilizing this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic compounds.Notably,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),respectively.Additionally,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and stability.This work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.
基金the National Natural Science Foundation of China(No.20772011)the Basic Research Foundation of Beijing Institute of Technology(No.3090050320906) for financial support for this work.
文摘Two new cage compounds,4-trinitroethyl-10-nitro-2,6,8,12-tetraacetylhexaazaisowurtzitane（3） and 4-trinitroethyl- 2,6,8,10,12-pentanitrohexaazaisowurtzitane（4）,containing trinitromethyl group were synthesized by a novel method,and their structures were confirmed by IR,;H NMR,MS and single crystal X-ray.DSC result shows that compound 4 has surprising thermal stability and could be a potential energetic compound.
基金Supported by the National Natural Science Foundation of China(Nos.20573098, 50846021 and 69075036)
文摘Two general expressions and their six derived formulae for estimating the critical temperature（Tb） of thermal explosion for energetic materials（EMs） were derived from the Semenov＇s thermal explosion theory and eight non-isothermal kinetic equations via reasonable hypothesis. We can easily obtain the values of the initial temperature（T0i） at which DSC curve deviates from the baseline of the non-isothermal DSC curve of EMs, the onset temperature（Tei）, the exothermic decomposition reaction kinetic parameters and the values of Too and Te0 from the equation Toiorei=Tooore0＋α1β1＋α2β2＋...＋αL-2βi^L-2, i=1, 2, …, L and then calculate the values of Tb by means of the six derived formulae. The results obtained with the six derived calculating methods for six trinitromethyl explosives： bis（2,2,2- trinitroethyl-N-nitro） ethylene diamine（BTNEDA）, 2,2,2-trinitroethyl-4,4,4-trinitrobutyrate（TNETB）, bis（2,2,2- trinitroethyl） formal（BNTF）, bis（2,2,2-trinitroethyl-nitramine）（BTNNA）, 2,2,2-trinitroethyl-2,2,2-trinitroethyl-N- nitroamino acetate（TNTNNA） and tetrakis [2,2,2-trinitroethyl] orthoester（TTNOE） agree well with each other.
