Synthesis And Process Optimization Of Nitroform And Its Derivatives

Nitroform(NF) is a kind of important organic intermediates that can synthesize other energetic materials. The chemical reaction ability of NF is so strong that it can be used to synthesize a serie of nitroform derivatives. The oxygen balance and energy of explosives introducing the trinitromethyl groups in the molecule can be significantly improved. Therefore, it is very important in the theory and practical significance to carry out a study on the synthesis of nitroform and its derivatives. As a kind of nitroform derivatives, N,N-bis(2,2,2-trinitroethyl)-nitramine(BTNNA) can be not only used as a carrier of cast explosives, an oxidizer of solid propellants, but the oxygen component of mixing explosives. The paper has improved and optimized the synthetic conditions of the raw material NF, the intermediate BTNA and the target BTNNA and synthesized several kinds of other nitroform derivatives with NF as the raw material, broadening the scope of application of nitroform.The NF was prepared by 4,6-dihydroxypyrimidine(DHP) and obtained its optimum conditions through experiments of varying the single factor. The nitration conditions are that the time is 3.5h, the temperature is 45℃ and the mole ratio of H2SO4, HNO3 and DHP is 1:2.5:3.5. The hydrolysis conditions are that the time is 60min and the temperature is 45℃.The production was extracted with CH2Cl2 and washed with H2O with the yield of 65.5%.BTNNA was prepared by BTNA with the NF as raw material and the optimum conditions of BTNA and BTNNA were obtained through single factor experiments and orthogonal experiments. The optimum conditions of BTNA are that reaction time is 55min, reaction temperature is 18℃ and the ratio of NF, HA, H2O and HNO3 is 6.6mmol:2.7mmol:16mL:1mL. The optimum conditions of BTNNA are that reaction time is 20min, reaction temperature is 30℃ and the ratio of BTNA, H2SO4 and HNO3 is 2.9mmol:3mL:5mL. BTNA and BTNNA were recrystallized by carbon tetrachloride with the yield of 91.9% and 93.6%. Thermal properties of BTNNA were also studied through DSC and TG-DTG. The results show that the decomposition temperature is 177.4℃ and its maximum weight loss peak is 168℃.Four kinds of nitroform derivatives such as 2,2,2-trinitroethanol(TNE), 1,1,1,4,4,4-hexanitrobutane-2,3-diol,1,1,1,3,5,5,5-heptanitropentane and TTNTA were synthesized with the raw material of NF. The structures of them were characterized by NMR analysis. The properties of TTNTA were predicted by quantum calculation. The theoretical density after optimizing predicted by Monte-Carlo method is 1.90g/cm. The heat, velocity and pressure of detonation predicted by Kamlet-Jacobs formula are 1805J/g,9.45km/s,40.90GPa, respectively. H50 of impact sensitivity is 60cm. With the mixture of nitic and sulfuric acid and fuming nitric acid/anhydride acetic acid, the nitration reaction of TTNTA was studied. The possible stuctures of the nitration products were suggested, providing a new thinking for the nitration study of TTNTA.