A fused heterocyclic high-temperature heat-resistant compound bis([1,2,4]triazolo)[1,5-b;5',1'-f][1,2,4,5]tetrazine-2,7-diamine(DATC)was synthesized from 3,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,2,4,5-tetrazine by substitu-tion,thermolysis and cyclization,and its molecule structure was characterized by elemental analysis,IR,NMR and HRMS anal-ysis.The mechanism of 3,6-bis(1 H-1,2,3,4-tetrazd-5-ylamino)-1,2,4,5-tetrazine(BTATz)thermolysis and cyclization re-action was discussed,and the optimization of reaction conditions was carried out.The morphology of DATC was characterized by SEM.The thermal performance of DATC was characterized by DSC and TGA and the physicochemical and detonation prop-erties of DATC were estimated based on density functional theory.The impact sensitivity and friction sensitivity of DATC were tested using a drop hammer and BAM friction tester.The results showed that DATC had a theorectical density of 1.827 g/cm3,heat of formation of+666.37 kJ/mol,thermal decomposition peak temperature of 477.9℃(DSC,10 ℃/min),theorectical detonation velocity of 7.80 km/s,and theorectical detonation pressure of 27.3 GPa.Its impact sensitivity was higher than 100J,and its friction sensitivity was higher than 360 N.It was well compatible with RDX,HMX,CL-20,4,8-di(2,4,6-trini-trophenyl)difuzan pyrazine(TNBP)and PYX.
The application of 3D printing technology in the performance regulation and control of aluminum-based energetic materials were exposited.The effects of 3D printing ink optimization and microstructure optimization on the burning rate and mechanical properties of molding materials were discussed.It is found that the addition of fluoropolymer or detachable polymer in the ink can significantly affect the initial reaction path of aluminum powder and adjust its ignition and combustion characteris-tics.As a binder in the application of energetic materials,it can rapidly release a large amount of gas products and inhibit the agglomeration of aluminum powder,which is a new path for future binder selection.The microstructure optimization of 3D printing energetic materials mainly utilizes methods such as changing the spatial structure,distribution gradient,and specific structure of components to improve the combustion efficiency of energetic materials.According to the current achievements and development trends,the combination of ink and microstructure optimization will be a potential direction for the manufac-ture process of energetic materials in the future.With 94 references.
To investigate the effect of damage on the reaction growth of 2,4-dinitroanisole(DNAN)based melt-cast explosive after ignition and to obtain the characteristic parameters of reaction growth,five groups of samples with different presets of damage were tested for reaction growth after ignition.In the reaction growth test after ignition,monochromatic light shielding technology was used to shield the strong light interference generated during the explosive reaction process;Using a high-speed camera equipped with a monochromatic light lens to observe and record the entire reaction growth process,and the image e-volution of the explosive reaction growth process was obtained.A pressure testing system was used to test the pressure change process inside the reaction vessel and to obtain the pressure change during the reaction growth process.The results show that the reaction growth process of DNAN-based melt cast explosive after ignition mainly includes ignition,slow reaction and fast reaction.In the test,the ignition delay time of the samples decreases with the increase of damage,except for the samples with 1.26％damage caused by extrusion.The average ignition delay time of the five groups of samples is 1.140ms.The duration of slow reaction decreases to 0 with the increase of damage degree,and the occurrence of damage accelerates the process of reaction growth.In the rapid reaction stage,the reaction duration and maximum pressure in the vessel decrease with the in-crease of damage degree.With the increase of damage degree,the maximum pressure change rate first increases and then de-creases,but it is greater than that of the samples without damage.In the samples with 0.44％damage degree stimulated by high temperature,the maximum pressure change rate is 13.67 MPa/ms.
In order to solve the problem for treating small quantities of waste gun propellants generated during production and use,in the independently established mobile small incinerator of energetic materials,three representative waste gun propellants of single-base,double-base and mixed nitric ester were selected to study the changes of pressure and temperature in the incin-erator and the effect of different flue gas treatment processes on the pollutants generated during incineration,especially NOx(NO and NO2).The results showed that the incinerator burning process was stable,the temperature and pressure in the incin-erator did not appear abnormal,and the incineration process was safe and reliable.The main pollutants of waste gun propel-lants incineration were NOx and CO.The secondary combustion technology was able to basically eliminate CO.The selective non-catalytic reduction(SNCR)technology reduced NOx by 68.56％,achieving ultra-low emission of pollutants.This study provides effective technical ways and means for the safe and clean treatment of small quantities of waste gun propellants.
To investigate the accuracy of the currently used three auxiliary methods(atomization energy,equivalent bonding and isodesmic reaction methods)for calculating the heat of formation(HOF)values,the structure optimization and frequency calculations were performed for 160 kinds of novel energetic molecules at the B3LYP/6-311G(d,p)theoretical level.The molecules were subject to single-point energy calculations at the MP2/6-311++G(d,p)theoretical level.The HOF values were calculated using the three commonly used auxiliary reactions(atomization energy method,equivalent bonding method,and atom equivalent method)by extracting thermodynamic values and electronic energies,where the results were compared with the HOF values directly output by the G4(MP2)-6X method,and the regression coefficients were fitted for each method.The linear regression equation was established,which can be used in combination with B3LYP/6-311G(d,p)//MP2/6-311++G(d,p)theoretical level to obtain the calculation accuracy of G4(MP2)-6X method.The enthalpies of formation of 160 kinds of substances at different theoretical levels and enthalpies of formation calculation methods were calculated.The correla-tion of the three methods was found to be:atomization energy method＞equivalent bonding method＞atom equivalent method.
