| C-N linked azole-based high-nitrogen energetic compounds have high nitrogen content,enthalpy of formation,and the product is environmentally friendly after decomposition.On the basis of the C-N linked high-nitrogen azoles,23 new metal energetic salts and organic salt have been designed and synthesized firstly.The structural characterization,thermal stability,the explosion and sensitivity properties were studied systematically.The main research content is as follows:The geometry optimization of 4 C-N linked azole-based high-nitrogen energetic compounds was carried out by using B3LYP/6-311++G**method employed in Gaussian03package in order to determine the most stable configurations,which provides theoretical basises for experimental work.Then,these four kinds of compounds were synthesized from3-amino-1,2,4-triazole,5-amino-1H-tetrazole and 3,5-diamino-1,2,4-triazole,and single crystals of three compounds were obtained.The structures were characterized by using elemental,infrared,mass spectrometry and X-ray single crystal diffraction analysis.Their thermal stability properties,detonation properties and the sensitivity performance were studied.Results show that compound 3 has the highest thermal decomposition temperature(247.8 oC);compound 4 has the highest formation enthalpy(809.25 k J·mol-1);compound 2has the highest detonation velocity(8212 m·s-1).8 kinds of metal salts based on the 1-(1H-1,2,4-triazole-3-yl)-1H-tetrazole were synthesized firstly and characterized by using modern instrumental analysis technology.And single crystals of five metal salts were obtained.The thermal stability of the metal salts was studied by DSC technology.Most of them have good thermal stability,and the decomposition temperature of lithium salts is highest with a value of 258 oC.The enthalpy of formation was calculated by the isometric reaction method,and the enthalpy of formation of two metal salts are higher than 1000 k J·mol-1.The detonation performance was estimated by using EXPLO5 software,and the impact sensitivity and friction sensitivity were tested.The results showed that these metal salt were insensitive energetic materials.11 kinds of metal salts based on 5-(tetrazole-1-yl)-2H-tetrazole were synthesized firstly and characterized by using modern instrumental analysis technology.And single crystals of four metal salts were obtained.The decomposition temperature of most metal salts is higher than 200 oC,and the values of both cobalt and copper salts are up to 300 oC.The detonation velocity and pressure were calculated as well.The cesium salt has good detonation performance(detonation velocity:9092 m·s-1).Results of the sensitivity test show that,copper salt(impact sensitivity:0.5 J,the friction sensitivity:5 N)and cobalt salt(impact sensitivity:1 J,friction sensitivity:96 N)are sensitive,they are hopefully used as primary explosive,the rest of the metal salts are insensitive to impact and friction.2 kinds of energetic salts based on 5-(tetrazole-1-yl)-2H-tetrazole were synthesized firstly and characterized by using modern instrumental analysis technology.And their crystal structures were confirmed as well.These salts have high nitrogen content and enthalpy of formation,and the 4-amino-1,2,4-triazole salt has good explosive performance(detonation rate:8157 m·s-1,detonation pressure:23.4 GPa).The impact sensitivity of these salts is greater than 40 J,and the friction sensitivity is greater than 360 N.They are potentially used as a safe and environmentally friendly material.2 metal salts based on 3,5-bis(tetrazole-1-yl)1,2,4-triazole were synthesized.The obtained 3,5-bis(tetrazole-1-yl)1,2,4-triazole anion provides novel method for the synthesis of new C-N linked azole-based high-nitrogen energetic compounds with three rings structures.The molecular structure and crystal structure were confirmed by using modern instrumental analysis technology.The thermal stability,detonation performance and sensitivity were studied.Results show that the compound has high enthalpy of formation(809.25 k J·mol-1),and its metal salts have good thermal stability and high enthalpy of formation.This series of compounds are insensitive to impact and friction. |
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