TGA, DSC and DFT Studies of TKX‐50, ABTOX and Their Key Precursors

Abstract

TKX‐50 (Dihydroxylammonium 5,5’‐bistetrazolate‐1,1’‐dioxide) and ABTOX (Diammonium salt of 5,5’‐bistetrazole‐1,1′‐diolate) being simple and cheap to prepare from commonly available chemicals, are emerging as promising energetic materials along with the advantages like required thermal insensitivity, low toxicity and safe handling. In order to synthesize such powerful materials with utmost care, it is essential to know about the precursors and reaction intermediates involved. Therefore, the detailed thermal analyses of various precursors such as glyoxime (I), dichloroglyoxime (II), diazidoglyoxime (III) and bistetrazoledihydroxide (IV) and final products viz., TKX‐50 (V) and ABTOX (VI) were carried out using differential scanning calorimetric and thermal gravimetric analysis experiments. The relative trend of band gap values calculated from the difference of HOMO and LUMO is well correlated with the decomposition temperatures (Tmax) values at a heating rate of 10 °C min−1 indicating the relative thermal stability of I–VI. The impact and friction sensitivity of ABTOX and TKX‐50 indicated that these compounds are safer than the currently known powerful explosives such as CL‐20. The calculated density impulse of TKX‐50 in rocket propellant formulations was found to be 499 g m−2 s−1 which is similar as that of HMX (494 g m−2 s−1). The theoretical performance prediction of TKX‐50 as the potential ingredient in gun propellant formulations indicated that the TKX‐50 could yield higher force constant (1471 J K−1) in comparison to currently known explosive such as RDX (1412 J K−1).

Theoretical evaluation of TKX‐50 as an ingredient in rocket propellants

“…The NASA SP‐273 computer code was used to predict the parameters of rocket propellant formulations, and was able to show that TKX‐50 containing formulations showed a superior specific impulse value compared to corresponding formulations in which TKX‐50 was replaced by other common explosives [14] . Based on this work, the authors concluded that the theoretically predicted data indicated that TKX‐50 has potential for application in rocket and gun propellants [14] …”

“…[14] Based on this work, the authors concluded that the theoretically predicted data indicated that TKX-50 has potential for application in rocket and gun propellants. [14] The properties of composite propellants containing TKX-50 have been investigated experimentally with different mass fractions of TKX-50 particles -specifically on TKX-50/HTPB binder slurries and AP/HTPB/Al propellant slurries. [15] It is possible with the inclusion of specially selected energetic materials to increase the gravimetric specific impulse or the density specific impulse of propellants, however, the energetic materials chosen for this purpose must show low sensitivity to external stimuli such as impact and friction.…”

“…[14] The NASA SP-273 computer code was used to predict the parameters of rocket propellant formulations, and was able to show that TKX-50 containing formulations showed a superior specific impulse value compared to corresponding formulations in which TKX-50 was replaced by other common explosives. [14] Based on this work, the authors concluded that the theoretically predicted data indicated that TKX-50 has potential for application in rocket and gun propellants. [14] The properties of composite propellants containing TKX-50 have been investigated experimentally with different mass fractions of TKX-50 particles -specifically on TKX-50/HTPB binder slurries and AP/HTPB/Al propellant slurries.…”

Computational design and screening of promising energetic materials: The coplanar family of novel heterocycle‐based explosives

“…Therefore, improving the stability of HEDMs and reducing its sensitivity is the main focus of current research in the field of materials science [5, 6]. Recently，studies have found that when the crystal structure of the compound is coplanar, it is beneficial to achieve a fine balance between the high‐energy properties and stability of HEDMs [7, 8]. For example, 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB) and 3,3′‐diamino‐4,4′‐azofurazan (DAAzF) with coplanar crystal structures have good stability and lower sensitivity [9, 10].…”

Decomposition Kinetics of Substituted Energetic Isowurtzitane Cage Molecules Hexanitrohexaazaisowurtzitane (CL‐20) and TEX: A Comparative Study

“…Thermal hazard assessment of TEX also has been carried out by using accelerating rate calorimeter and the results are reported in literature . There are reports wherein, computational and experimental techniques have been used to determine the thermal behaviour of energetic molecules …”