Synthesis, Structure And Properties Of BPTAP Energetic Derivatives Based On Amino Modification

Finding heat-resistant compounds with high energy and low sensitivity and thermal stability for practical applications is still a huge challenge for energetic materials research.In the field of energetic compounds,the detonation performance of a compound is usually improved by introducing a substituent with a high enthalpy of formation,and the thermal stability of a compound can often be improved by selecting a more stable skeleton.The stable energetic framework is the focus of research in the field of heat-resistant explosive synthesis.The research found that the existing benzene,fused ring and fused ring skeletons of the existing heat-resistant energetic compounds have good skeleton stability due to their significant aromaticity and conjugated properties,and have been favored by researchers.In addition,the use of amino groups as substituents to enhance the overall stability of compounds by hydrogen bonding with nitro groups is one of the simplest and most classic methods to improve the stability of energetic compounds.Lattice energy can increase,thereby increasing the melting point or decomposition temperature of the compound.At the same time,the hydrogen bonding of the amino group can shorten the molecular distance,increase the crystal packing coefficient of the compound,and increase the density of the compound.This paper proposes a design strategy for incorporating amino groups into thermally stable high-energy materials and applying them to BPTAP?tetranitrobenzo-1,3a,4,6a-tetraazapentadienepyridine?.In the benzene ring of an existing nitro group,an amino group?-NH₂?was introduced at the ortho position of the nitro group,and several high-energy derivatives were synthesized through modification.The relationship between structure and performance was analyzed by crystal structure and stacking characteristics,which opened the door to tetraazapentene chemistry and described the practicality of combining intra-and intermolecular hydrogen bonding into heterocyclic fused rings.?1?Several suitable amino-substituted BPTAP derivatives were synthesized through appropriate amino introduction strategies.The synthesized tetraazapentene compounds were characterized by structural characterization,molecular force analysis,molecular electrostatic potential analysis,sensitivity and thermal stability.Test and theoretical study of detonation performance.The results show that the compounds 8-b?4,9-diamino-2,8,10-trinitrobenzo-[1,3a,4,6a]-tetraazapentadienepyridine?with high density(1.84 g.cm^-3),high nitrogen content?37.43%?,low sensitivity?IS:12 J,FS>360 N?,and thermal stability equivalent to HNS?320^oC?.In addition,it has a theoretical detonation performance(D:7933 m.s^-1)that is superior to HNS(D:7612 m.s^-1)and BPTAP(D:7670 m.s^-1).?2?Compared with BPTAP,compound 8-b has lower hydrogen sensitivity due to the introduction of amino groups in the molecule,which makes it less sensitive.It can be used as an excellent high-energy,heat-resistant,insensitive energetic material.Compound 2?4-diamino-2,8,10-trinitrobenzo-[1,3a,4,6a]-tetraazapentadienepyridine?has lower energy and sensitivity than compound 8-b,but its thermal stability?343 ^oC?is better than HNS and compound 8-b,has a detonation speed equivalent to BPTAP(7547 m.s^-1),and its sensitivity is also better than BPTAP?impact sensitivity:10 J;friction sensitivity:240 N?.Detonation velocity of compound 7-a?4-chloro-3,5,9,11-tetranitrobenzo-[1,3a,4,6a]-tetraazapentene-pyridine?,Explosion pressure?27.44 GPa?,impact sensitivity?3 J?,friction sensitivity?160N?,its detonation performance is better,but its sensitivity is higher and its impact is only 3J,which can be used as a good detonator.?3?The relationship between the structure and properties of amino and its derivatives and heat-resistant energetic backbones was studied.By analyzing the structure and properties of synthetic BPTAP derived compounds,it was first proved that this amino-binding strategy could be used to develop insensitive high-energy heat-resistant materials Effective means.Although an amino group was introduced into the nitrobenzene ring to improve the thermal stability of the compound,this modification through the amino group still disrupted the original equilibrium of the compound and failed to form a ring.The closed cyclic hydrogen bonding interaction is similar to the TATB ring mode,which in turn affects its thermal stability decisively.Therefore,in order to construct super-heat-resistant high-energy materials,the integrity of the intramolecular hydrogen bonding interactions in different heterocyclic systems must be considered,which is the key to successfully obtaining compounds with ideal properties.