The Synthesis, Structural Characterization Of Organic Salts Of The Nitro Enamine Structure

The development of novel high-energy compounds is still the currently significant research field of energetic materials.1,1-Diamino-2,2-dinitroethylene (FOX-7), for its super high energy density with high thermal stability and low sensitivity to impact and friction, is expected to become the important preferred component of propellant in future. In the study, FOX-7 was used as a mother compound to synthesize serial derivatives and their salts, from where we could hope to obtain the high energy compound and energetic flame suppressor with preferable performance. The thesis will offer theoretical foundation and performance parameters for future application in national defense.Targeted at exploiting the superior performance of FOX-7 and searching for more ideal novel energetic materials, eight derivatives of FOX-7 and their salts were synthesized, only one single crystal was firstly obtained and the structure were determined by four-circle X-ray diffractometer. The eight new compounds are:1-Amino-1-ethylamine-2,2-dinitroethene---AEFOX-71-Amino-1-(2,4-dinitrophenylhydrazine-yl)-2,2-dinitroethylene---APHDNEPotassium salt of AHDNE---K(AHDNE)Cesium salt of AHDNE---Cs(AHDNE)Guanidine salt of AHDNE---G(AHDNE)Rubidium salt of DNDZ---Rb(DNDZ)Cesium salt of DNDZ---Cs(DNDZ)Guanidine salt of DNDZ---G(DNDZ).Gaussian-03w package was used to optimize structure geometry and compute frequencies of the compounds. The optimized parameters, natural atomic charges, frontier orbital energy and main atomic orbital percentage were provided.The thermal behaviors of the above eight compounds were studied under non-isothermal conditions by DSC and TG/DTG methods. The Kissinger method, Ozawa method, differential method and integral method were employed to determine kinetic parameters and thermal decomposition mechanism functions of K(AHDNE),Cs(AHDNE,G(AHDNE,Cs(DNDZ) and G(DNDZ) in exothermic processes. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), Gibbs free energy of activation (ΔG≠) and critical temperature of thermal explosion (Tb) of the eight compounds were obtained.The continuous specific heat capacity of the eight new compounds were determined. Based on the Cp results, the thermodynamic values (enthalpy, entropy and Gibbs free energy) of compounds between 283～353 K, relative to the standard temperature 298.15 K, were derived through thermodynamic equations. Meanwhile, using Cp functions and thermal decomposition parameters, the adiabatic time-to-explosion of K(AHDNE),Cs(AHDNE),G(AHDNE),Cs(DNDZ),G(DNDZ),APHDNE and AEFOX-7 were estimated, as an important parameter, which can be used to estimate thermal stability and safety of engetic materials directly.