Study On Spheroidization Of Nitroguanidine And Synthesis Of Its Derivatives

Nitroguanidine is one kind of important energetic material, has important applications in pesticide, medicine and other fields of solid rocket propellant. Nitroguanidine has excellent explosion property, good stability, low sensitivity to impact and friction, nearly insensitive, so it is usually used as insensitive propellant and explosive charge composition. It has important meaning to study the nitroguanidine spheroidizing process and derivatives. The main content of this thesis are presented as follows:Spheroidal nitroguanidine of higher bulk density was prepared from needle shaped nitroguanidine by solvent non-solvent method, which uses N-methyl pyrrolidone as solvent, acetone as non solvent, nickel nitrate as additive. The crystal morphology of spherical nitroguanidine is analyzed by scanning electron microscope and thermal properties istested by differential scanning calorimetryn(DSC). Single factor test was carried out to study the main factors that affect the bulk density of nitroguanidine. The technical process of preparing spheroidal nitroguanidine of higher bulk density was also invesfigated.The results show that the bulk density of the spheroidal nitroguanidine is 1.08 g·m-3 under conditions of 80℃, the volume ratio of solvent and non-solvent of 1:3, the additive mass fraction of 0.005%, and the stirring rate of 400 r·min-1. The thermal properties of spherical nitroguanidine has been improved.N-methyl-N’-nitroguanidine,3-amino-1-nitroguanidine,1-aceto-2-nitroguanidine were synthesized by using nitroguanidine as raw material, the reaction between these derivatives and ethylene aldehyde was studyed. Their structures were characterized by NMR, IR and MS, Their process conditions were optimized.Three energetic salts were synthesized by double decomposition using 5-nitrotetrazole, 3-hydroxyl-5-nitrotetrazole and 3,5-dininitro-1,2,4-triazole as anion, using 3-amino-1-nitroguanidine as cation. Their structures were characterized by NMR, IR and MS, and the crystalline structure of 3-amino-1-nitroguanidine 3-hydroxy-5-nitro tetrazole salts were determined by X-ray single crystal diffraction analysis. The crystal belongs to triclinic system with space group p-1, and the crystal parameters of this compound are a=6.6130(13) A, b=12.814(3) A, c=14.279(3) A, a= 102.21(3)°, p=98.O8(3)°,γ=93.74(3)°, Z=2, Dc=1.683 g·cm-3, u=0.161 mm-1, F(000)=61. Their enthalpy of formation, detonation velocity and detonation pressure calculated by Kamlet-Jacbos formula and Born-Haber cycle. The results indicate that the enthalpy of formation, detonation velocity and detonation pressure of 3-amino-l-nitroguanidine 3-hydroxy-5-nitrotetrazole salt are 467.0 kJ/mol,8.642km/s and 31.80 GPa, that the enthalpy of formation, detonation velocity and detonation pressure of 3-amino-l-nitroguanidine 3,5-dininitro-l,2,4-triazole salt are 353.7 kJ/mol,8.417 km/s and 29.80 GPa, and that the enthalpy of formation, detonation velocity and detonation pressure of 3-amino-l-nitroguanidine 5-nitrotetrazole salt are 487.2 kJ/mol,8.612 km/s and 32.00 GPa.