Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (10): 2071-2078.doi: 10.3866/PKU.WHXB201304251


Thermal Safety of 2,2,2-Trinitroethyl-N-nitromethyl Amine

HU Rong-Zu1,3, ZHAO Feng-Qi1, GAO Hong-Xu1, MA Hai-Xia2, ZHANG Hai3, Xu Kang-Zhen2, Zhao Hong-An4, YAO Er-Gang1   

  1. 1 Science and Technology on Combustion and Explosion Laboratory, Xi’an Modern Chemistry Research Institute, Xi’an 710065, P. R. China;
    2 College of Chemical Engineering, Northwest University, Xi’an 710069, P. R. China;
    3 Department of Mathematics/Institute of data analysis and computation chemistry, Northwest University, Xi’an 710069, P. R. China;
    4 College of Communication Science and Engineering, Northwest University, Xi’an 710069, P. R. China
  • Received:2013-01-29 Revised:2013-04-23 Published:2013-09-26
  • Contact: HU Rong-Zu
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173163, 21073141, 11171272).


To evaluate the thermal safety of 2,2,2-trinitroethyl-N-nitromethyl amine (TNMA), basic data, including specific heat capacity (Cp) and thermal conductivity (λ), were estimated using empirical formulae. The standard enthalpy of formation of TNMA, ΔfHmθ(TNMA, s, 298.15 K), was calculated by an additive method of contributing bond energy to heat of formation Qf, and the standard combustion enthalpy ΔcHmθ(TNMA, s, 298.15 K) and standard combustion energy ΔUmθ (TNMA, s, 298.15 K) and standard combustion energy ΔUmθ (TNMA, s, 298.15 K) were calculated by thermodynamic formulae. The detonation velocity, detonation pressure, and heat of detonation were estimated using the Kamlet-Jacobs equation. The heat of decomposition reaction (Qd) of TNMA was estimated by an empirical formula, and the thermal behavior of TNMA was studied by differential scanning calorimetry (DSC). The kinetic parameters of the exothermic decomposition reaction of TNMA were obtained from analysis of DSC curves and standard volume of gas evolved (VH) vs time (t) curves determined using a highly sensitive Bourdon glass membrane manometer. The parameters used to evaluate the thermal safety of TNMA, such as the self-accelerating decomposition temperature (TSADT), critical temperature of thermal explosion (Tbe and Tbp), adiabatic time-to-explosion (tTIad), 50% drop height (H50) of impact sensitivity, critical temperature of hot-spot initiation (Tcr), thermal sensitivity probability density function S(T) for infinite plate-like, infinite cylindrical and spheroidal TNMAwith half-thickness and radius of 1 m at 300 K, peak temperature corresponding to the maximum value of the S(T) vs T curve (TS(T)max), safety degree (SD), critical thermal explosion ambient temperature (Tacr), and thermal explosion probability (PTE), were obtained by the above-mentioned basic data. Results show that (1) TNMA has better thermal safety and heat-resistent ability; but in comparison with cyclotrimethylenetrinitramine (RDX), the transition from thermal decomposition to thermal explosion of TNMA is easy to take place. (2) The thermal safety of large scale TNMA with different shape decreases in the order: sphere>infinite cylinder>infinite plate. (3) TNMA has high standard combustion energy and high chemical energy (heat) of detonation, and explosion performance level approaching that of HMX. It is sensitive to shock, has impact sensitivity level approaching those of pentaerythritol tetranitrate (PETN) and tetryl and can be used as a main ingredient of composite explosive.

Key words: TNMA, Thermal decomposition, Thermal safety, Thermal explosion