Un explosivo portador de alta densidad y baja sensibilidad que promete reemplazar al TNT: 3-bromo-5-fluoro-2,4,6-trinitroanisol

Buscando un reemplazo del TNT, los autores de este artículo utilizaron un método químico para sintetizar un nuevo explosivo: 3-bromo-5-fluoro-2,4,6-trinitroanisol (BFTNAN). Los resultados de los ensayos mostraron que la entalpía de formación de BFTNAN fue 72,6 kJ·mol-1. A una velocidad de calentamiento de 20 ℃·min-1, el pico de descomposición térmica de BFTNAN es a TP=250,6 ℃, y la energía de activación es EK=80 kJ·mol-1, que está cerca de los valores de Tp y EK del TNT. Esto indica que BFTNAN es un explosivo relativamente fácil de descomponer, pero la velocidad de descomposición no es rápida. La temperatura crítica para la explosión térmica de BFTNAN alcanzó Tb=216 ℃, que también está cerca del valor Tb de TNT. La sensibilidad al impacto y a la fricción del BFTNAN fue menor que la de TNT, que estaba cerca de la de DNAN. La sensibilidad térmica de BFTNAN es más baja que TNT. La velocidad de detonación y el calor de explosión del explosivo fundido basado en BFTNAN fueron claramente superiores a los de los explosivos basados en TNT. Especialmente, el explosivo fundido a base de BFTNAN ha mostrado ventajas en almacenamiento de energía química, capacidad de trabajo, brisancia y capacidad de aceleración de metales.

Abstract

To address the issues of high saturated vapor pressure, high toxicity, and high viscosity of TNT, this article used a chemical method to synthesize a new carrier explosive BFTNAN. The prepared samples were characterized using scanning electron microscope(SEM), energy spectrum(EDS), x-ray diffraction(XRD), infrared spectrum(IR), x-ray photoelectron spectroscopy(XPS), nuclear magnetic resonance, and elemental analysis techniques. The enthalpy of formation of BFTNAN was measured using a specialized calorimeter that is specially used in testing of explosives and powders. The thermal decomposition performance of BFTNAN was tested by DSC technology. Meanwhile, the mechanical sensitivity, thermal sensitivity, and detonation performance of BFTNAN based melt-cast explosive was also tested. The results of characterizations showed that the prepared sample was indeed BFTNAN. The enthalpy of formation of BFTNAN was determined as ΔH_f,BFTNAN = −72.6 kJ·mol⁻¹. At a heating rate of 20 °C·min⁻¹, the thermal decomposition peak of BFTNAN is at T_P = 250.6 °C, and the activation energy is E_K = 80 kJ·mol⁻¹, which is closed to the T_p and E_K values of TNT. This indicates that BFTNAN is a relatively easy to decompose explosive, but the decomposition rate is not fast. The critical temperature for thermal explosion of BFTNAN reached T_b = 216 °C, which is also closed to the T_b value of TNT. The impact and friction sensitivity of BFTNAN were lower than those of TNT, which was closed to those of DNAN. The thermal sensitivity of BFTNAN is lower than TNT. The detonation velocity and heat of explosion of BFTNAN based melt-cast explosive were distinctly higher than those of TNT based explosive. Especially, BFTNAN based melt-cast explosive were of the advantages in chemical energy storage, work capacity, brisance, and ability of acceleration metals.

Fuente: https://www.sciencedirect.com