ИСТИНА

Effect of the nitration agent nature on the isomeric composition of the reaction products of 2,6-dioxodecahydro-1H,5H-diimidazo[4,5-b:4’,5’-e]pyrazine (TC) in a wide range of acidity has been studied. Conditions for synthesis of tetra-, penta-, and hexanitro derivatives of TC have been optimized. A new method for preparation of high energetic compound 1,3,4,5,7,8-hexanitro-2,6-dioxodecahydro-1H,5H-diimidazo[4,5-b:4’,5’-e] pyrazine via a new nitric acid salt of 2,6-dioxodecahydro-1H,5H-diimidazo[4,5-b:4’,5’-e] pyrazine has been proposed. A study on interconversion of the TC tetranitro derivatives has shown that 1,4,7,8-tetranitro-2,6-dioxodecahydro-1H,5H-diimidazo[4,5-b:4’,5’-e]pyrazine proves to be more reactive than 1,4,5,8-tetranitro-2,6-dioxodecahydro-1H,5H-diimidazo[4,5-b:4’,5’-e]pyrazine in the nitration reaction in acidic environment. Burn rate study in a constant-pressure bomb of four derivatives has been done. It has been shown that tetra and penta derivatives of TC, all demonstrate higher burning rate and lower pressure exponent than HMX. Among these molecules the pentanitro derivative demonstrates the highest burning rate, which is almost twice as higher as that of HMX at pressure of 10 MPa. A correlation has been found between the burning rate of the nitamines and their thermal stability, indirectly characterized by the ignition temperature. The fastest burning rate proved to be characteristic of the least stable three-cyclic nitramine, pentanitro derivative of TC.