5-Nitro-2,4-Dihydro-3H-1,2,4-Triazole-3-One (NTO)

Abstract

NTO is a very attractive explosive due to its insensitivity, thermal and mechanical stability. NTO can be used to prepare melt-cast explosives (NTO-TNT mixture) as well as pressed explosives with thermoplastic binder and cast PBX charges for Insensitive Munitions. In this chapter, various synthesis processes and physico-chemical properties of NTO are discussed. A number of formulations along with there explosive properties are presented and compared with neat NTO and TNT. The toxicity, biodegradation, and detection techniques are also discussed in this chapter. 5.1 Introduction Both 5-Nitro-2,4-dihydro-3H-1,2,4-triazole-3-one and 3-Nitro-2,4-dihydro-3H-1,2,4-triazole-5-one are abbreviated as NTO and are considered as a potential insensitive replacement for RDX in various explosive formulations. 5-Nitro-2, 4-dihydro-3H-1,2,4-triazole-3-one and 3-Nitro-2,4-dihydro-3H-1,2,4-triazole-5-one are isomers, and, therefore, have similar properties. NTO is a low sensitive material and has been in use since 1980s. Its performance is slightly less than RDX, but either similar or superior to other explosives. However, the high yields and the availability of raw materials coupled with its excellent properties have made NTO a preferred material compared to TATB, RDX and HMX. NTO is thermally stable and exhibits low sensitivity to radiation damage and other stimuli. Therefore, it is relatively easy to transport and store. 5.2 Synthesis The first reported synthesis of NTO appears to be by Manchot and Noll [1], which was followed by Chipen et al. [2]. Several synthesis routes have been developed during 1980s. Synthesis of NTO is a two step process. In the first step triazol-3-one