Molecular structure aspects of initiation of some highly thermostable polynitro arenes

The paper is focused on 2,4,6,4′,6′,2″4″6″-octanitro[l,1′,3′,1″]terphenyl (ONT), 2,2′,2″4,4′,4″6,6′,6″-nonanitro[l,l′,3′,1″]terphenyl (NONA), 2,4,6-tris(2,4,6-trinitrophenyl)-1,3,5-triazine (TPT), N,N-bis(2,4-dinitrophenyl)-2,4,6-trinitroaniline (NTFA), 1,3,7,9-tetranitro[l,2,3]benzotriazolo[2,l-a][l,2,3]benzotriazole-5,11-diium-6,12-diide (TACOT-Z), 2,2′,4,4′,6,6′-hexanitrobiphenyl (HNB), 1,3-dinitrobenzene (1,3-DNB), 1,3,5-trinitrobenzene (TNB) and 2,4,6-triamino-1,3,5-trinitrobenzene (TATB). The initiation reactivity of these substances has been studied by means of the data obtained from non-isothermal differential thermal analysis (DTA), their ignition temperatures, impact sensitivity, the data obtained from the Russian manometric method, the detonation characteristics, DFT B3LYP/6-31G(d,p) charges on the nitrogen atoms of nitro group qN(NO2) and net charges of these groups Q(NO2). For comparison, also the data published and calculated on 2,2′,2″,2‴,4,4′,4″,4‴,6,6′,6″,6‴-dodecanitro[l,3′,1′,1″]quaterphenyl (DODECA) have been included. The paper specifies and discusses the relationships between the results of various methods used, inclusive between their outputs and charges and net charges of the primarily reacting nitro groups in the initiations. Relations of these charges to the characteristics of thermal reactivity, detonation and impact sensitivity confirm presumption about the identity of primary chemical processes in the initiation by heat (low-temperature thermolysis), shock and impact. The technologically most attractive substances can be ordered in the sequence TACOT ≥ ONT > TPT > NONA ≫ NTFA > TATB according to their decreasing thermal stability.