National Civil Blasting Equipment Quality Supervision and Testing Center

Nanjing, China

National Civil Blasting Equipment Quality Supervision and Testing Center

Nanjing, China
SEARCH FILTERS
Time filter
Source Type

Yang J.-Q.,Nanjing University of Science and Technology | Wang G.-X.,Nanjing University of Science and Technology | Gao P.,National Civil Blasting Equipment Quality Supervision and Testing Center | Gong X.-D.,Nanjing University of Science and Technology
Hanneng Cailiao/Chinese Journal of Energetic Materials | Year: 2013

Five structurally similar -ONO2 and -N3 derivatives of pentaerythritol, including tetraazido pentaerythritol (TAPE), pentaerythritol triazido nitrate (PTAN), pentaerythritol diazido dinitrate (PDADN), pentaerythritol azido trinitrate (PATN), and pentaerythritol tetranitrate (PETN) were studied by the B3LYP/6-31G * method. The molecular geometric configurations were optimized and vibration analyses were performed. Their densities, heats of formation, thermodynamic functions, detonation performances and specific impulses were estimated. The bond dissociation energy (EBD) of the possible trigger bond and the activation energy (Ea) of the hydrogen transfer reaction were computed. The results show that in comparison with PTAN, PDADN, PATN and PETN, TAPE has the maximum heat of formation among five derivatives and specific impulse level approaching that of PETN. The detonation performance and stability of PATN are close to those of PETN, and better than that of other derivatives, including PDADN. The pyrolysis of TAPE with -N3 is initiated from the transfer of H to -N3 which leads to the elimination of N2 and has an Ea of 130.57 kJ·mol-1. The pyrolysis of other derivatives containing -ONO2 is started from the rupture of the O-NO2 bond with an EBDof 130.91~137.45 kJ·mol-1. These energy values satisfy the stability requirements for the energetic compounds.


Yang J.,Nanjing University of Science and Technology | Zhang X.,Nanjing University of Science and Technology | Gao P.,National Civil Blasting Equipment Quality Supervision and Testing Center | Gong X.,Nanjing University of Science and Technology | Wang G.,Nanjing University of Science and Technology
RSC Advances | Year: 2014

A set of energetic aliphatic azido nitramines was designed and studied with the B3LYP/6-31G∗ method of density functional theory to find new promising azido nitramines applicable to propellants as plasticizers and to investigate the effect of the methylene nitramino group (-CH2NNO2-) on performance. The reliability of the theoretical method was tested by comparing the theoretical densities with the experimental data. The thermodynamic properties (heat capacity, enthalpy, entropy, and heat of formation), density (ρ), detonation pressure (P), detonation velocity (D), specific impulse (Is) and stability were predicted. With the increase in the number of -CH2NNO2- groups (n), the thermodynamic properties, ρ, P, and D increase, while the stability decreases slightly. There are linear relationships between thermodynamic properties and n. A -CH2NNO2- group improves the heat of formation by 67.59 kJ mol-1 on average. Is reaches the maximum when n = 4 and changes little when n ≥ 5. It is worth noting that Iss of all title compounds are higher than that of HMX (1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, a famous explosive). © the Partner Organisations 2014.


Yang J.,Nanjing University of Science and Technology | Zhang X.,Nanjing University of Science and Technology | Gao P.,National Civil Blasting Equipment Quality Supervision and Testing Center | Gong X.,Nanjing University of Science and Technology | Wang G.,Nanjing University of Science and Technology
RSC Advances | Year: 2014

Molecular dynamics (MD) and dissipative particle dynamics (DPD) simulations were performed to investigate the compatibility and mechanical properties of GAP (glycidyl azido polymer, an azido binder) and DIANP (1,5-diazido-3-nitrazapentane, an azido plasticizer). To determine the appropriate simulated chain length (n) of GAP, the solubility parameter (δ) was examined with n = 5, 10, 20, 30, and 40. The obtained δ decreases with the increasing n and when n reaches to 20, δ changes little and gives good agreement with the experimental data. Considering the computational costs, the chain length of GAP was selected to be 20. Then a series of blending systems of GAP (n = 20) and DIANP with mass ratios of 78.4/21.6 (I), 57.7/42.3 (II), and 37.7/62.3 (III) were constructed and studied. Results of solubility parameters, Flory-Huggins interaction parameters, blend binding energy distributions and mesoscopic morphologies all show that GAP and DIANP have good miscibility with each other. Compared with the mechanical properties of the pure GAP, it is found that addition of DIANP can enhance the plastic properties of GAP and the blend II has the best tenacity and ductility. This journal is © the Partner Organisations 2014.

Loading National Civil Blasting Equipment Quality Supervision and Testing Center collaborators
Loading National Civil Blasting Equipment Quality Supervision and Testing Center collaborators