Study On Syntheses And Properties Of Pentazolate Ionic Salts Based On Triazole Cations

Pentazole anions and their derivatives have become potential high energy density materials（HEDMs）due to their characteristics of high nitrogen content,high density,high formation enthalpy and clean and pollution-free detonation products.Since the realization of cutting off aryl-pentazole to obtain stable pentazole compounds,more and more pentazole metallic and nonmetallic salts have been synthesized and studied.Although pentazole metal salt is relatively easy to prepare,the energy of metal pentazole metal salt is limited because of the small contribution of metal cation to the overall energy of compound.Therefore,the preparation of nonmetallic pentazole salts by ion replacement is gradually becoming an important way to promote the practical application of pentazole compounds.This paper first explored the synthesis the precursor of pentazole ion salt,the amplification process of aryl-pentazole was studied on the basis of3,5-dimethyl-4-hydroxyaniline hydrochloride has been achieved 100 grams of amplification.The results of several experiments show that the temperature and feeding speed have an effect on the yield of the final product in the process of diazotization and ring closing reaction,and the optimal conditions of reaction with 600g hydrochloride as raw material are summarized.Followed by five explore the amplification process of cobalt salt hydrate,found the reason of low cobalt salt production rate in cut off in the amplification effect of aryl five azole section,too much of the reactant inevitable uneven phenomenon,mass and heat transfer and long reaction time and post-processing step of easy to cause the pentazolate anion decomposition,according to this kind of problem,In this paper,optimization suggestions are given for further research.Secondly,two kinds of nonmetallic pentazole salts based on amino or hydrazyl substituted triazole cations were synthesized by substitution reaction with AgN₅,and fully characterized by X-ray single crystal diffraction,¹H NMR,¹³C NMR and TG-DSC.The existence of polyamino groups in these cations makes a lot of hydrogen bonds participate in the N₅ˉstability.From the crystal structure,the two pentazole salts form an ordered layered stacking structure,which is proved by theoretical calculation to be the result of hydrogen bonds and extensiveπ-πinteractions.This special stacking structure brings excellent mechanical sensitivity.The friction sensitivity of the two pentazole salts is bigger than 360N and the impact sensitivity is bigger than 40J.At the same time,the detonation velocity and pressure of the two compounds are greater than TNT.And then to explore regularity in single crystal structure in pentazole ionic salt,three nonmetallic pentazolate were synthesized based on triazole cations which have azide,methyl and armour amidine,them were fully characterized by single crystal X-ray diffraction（XRD）,infrared（IR）,nuclear magnetic analysis and the simultaneous thermal analysis,but failed to get all of the single crystal structure,but it also has good thermal stability and mechanical sensitivity.Through the synthesis of these pentazole salts,we found the structural characteristics of triazole cationic pentazole salts,which can achieve the balance of detonation performance and stability to a certain extent.It not only enriches the types of pentazole nonmetallic salts,but also helps to explore more stable and higher performance pentazole salts from the crystal structure level.