Study On Synthesis Of Novel Insensitive Explosive 1-Methl-4,5-nitroimidazole,Performance And Apply

Multi-nitroimidazole are one of the important new high density energetic materials because of its high strain energy associated with their five member ring. So it is important to study the synthesis and properties of Multi-nitroimidazole for the theoretical study and military applications.1-Methl-4,5-nitroimidazole was synthesized with N-methylimidazole as initial material by one step nitrification reaction. And structure was characterized by IR,HNMR and ESI-MS. The influences of reaction temperature and reaction time on the yield of 4,5-MDNI was studied,. An optional production condition was obtained by the orthogonal experiment: Molar ratio of methl-imidazole, fuming sulfuric acid, fuming nitro acid is 1︰5.49︰6.56, reaction time 2h , reaction temperature 120℃, the yied is 25.51%.The singer crystal of 4,5-MDNI was obtained by slow evaporation of a solvent at room temperature and the crystal structures was determined by a four-circle X ray diffractometer . Crystals structures show the structures of 4,5-MDNI : Orthorhombic ,Pna2(1)/n, a=8.4123 ?,b= 12.646 ?,c= 6.5627 ?,V=698.2 ?3,Z=4, D=1.637g/cm3, F(000)=352 .Density is 1.63 g/cm3 by methods of density bottle, detonation is 7463m/s , and exlosion pressure is 22.9GPa by experience of kamlet formula , the impact sensitivity (10 kg) h50 of 4,5-MDNI is 87.5cm.The DSC-TG techniques were used to study the thermal behavior of 4,5-MDNI. The Kissinger method, Ozawa method, the integral method were carried out to determine the kinetic parameters, the apparent activation energy (E) and the pre-exponential (A) of 4,5-MDNI in the exothermic processes . The thermal decomposition mechanism function was got. CL-20 was coated with a little 4,5-MDNI by melting ,dispersion and cooling crystallization to CL-20 surface in water ,a kind of double-deck composite explosive with low mechanical sensitivity ,in which inside layer is CL-20 and outsider is 4,5-MDNI. Microscopic structures were analyzed by SEM with the variety of technical condition of coat. The impact sensitivity(2.5Kg) results show that the composite explosive reduce from 72% to 8%. Compatibility of double layer composite explosive was studied by DSC.