The investigation on the properties of TNBI and its salts

摘要

The main purpose of this study was to synthesis new ionic derivatives of 4.4' ,5,5'-tetranitro-IH,lH'-2,2'-biimidazole (TNBI) which can be used as modern secondary explosives. Firstly, an attempt was made to fully characterize TNBI dihydrate. The compound was examined with spectroscopic methods, elemental analysis, thermal analysis and small scale safety testing (impact and friction sensitivity). The results of experimental investigation of explosive properties of TNBI·2H_2O were also presented. Non-isothermal kinetics analysis, calorimetric measurements, detonability tests, detonation velocity measurements and cylinder tests were performed. Results of the cylinder tests were used to determine the acceleration ability of TNBl·2H-2O detonation products. The known salts of TNBI with guanidine, aminoguanidine, diaminoguanidine, triaminoguanidine and ammonia were obtained to confirm their interesting properties. The group of the new compounds includes salts with semi-carbazide, carbohydrazide, acetamidine, adenine, cytosine, 3-amino-l ,2,4-triazole, 4-amino-1,2,4-triazole, 3,5-diamino-1,2,4-triazole and 5-aminotetrazole. The structure of the molecules was proposed on the basis of the results obtained by methods of nuclear magnetic resonance and elemental analysis. Thermal properties were examined by differential thermal analysis and thermogravimetry. In order to determine the safety of the production and use of the new compound sensitivity to impact and friction tests were performed. Detonation parameters were calculated with CHEETAH code for density determined for pressed sample of TNBI dihydrate. The explosive properties were determined for the TNBI salt with semi-carbazide. This compound was selected for the further investigation because of its insensi-tivity, high theoretical detonation parameters and inexpensive synthesis. The study showed that the salt could be used as a secondary explosive material but it has lower detonation parameters and acceleration ability than 2,4,6-trinitrotoluene.