Studies on 3,30-diamino-4,40-azofurazan (DAAF)
Table 4 Performance comparison between DAAF and TNT
Sample
Melting/
°C
Density/
g cm-3
Nitrogen content/% Oxygen balance/% Impact sensitivity/cm Pressure/
GPa
Velocity/
km s-1
TNT [20] 81.8
DAAF 315
1.650
18.50
57.13
-73.96
-65.31
170
19.50
23.61
6.88
7.31
1.728 [6]
320 [7]
M = 196.05 g/mol,
q = 1.728 g cm-3
,
DfHhm
=
capacity is 215.53 J mol-1 K-1 at 298.15 K. The enthalpy
change, entropy change and Gibbs free energy change of
DAAF were derived in the temperature range from 253 to
373 K with temperature interval of 10 K. The combustion
energy of DAAF was measured with an oxygen-bomb
calorimeter. The combustion energy (DcU), standard molar
enthalpy of combustion (DcHhm) and standard molar
enthalpy of formation (DfHhm) at 298.15 K are -(13,188.43
32.77) J g-1, -(2575.68 6.42) kJ mol-1 and 429.98
6.44 kJ mol-1, respectively. The detonation velocity and
detonation pressure are 7.31 km s-1 and 23.61 GPa.
429.98 kJ mol-1 into Kamlet–Jacobs Eqs. (9–13) [19].
b þ 2c þ 2d
N ¼
ð9Þ
48a þ 4b þ 56c þ 64d
56c þ 88d À 8b
Mg ¼
ð10Þ
ð11Þ
b þ 2c þ 2d
28:9b þ 47:02ðd À b=2Þ þ 0:239DfHmh
Qd ¼
 103
M
ꢀ
ꢁ
D ¼ 1:01 NM1=2Q1d=2 1=2ð1 þ 1:30qÞ
P ¼ 1:558NM1=2Qd1=2q2
ð12Þ
ð13Þ
Acknowledgements Thanks are due to Prof. H. X. Ma, School of
Chemical Engineering, Northwest University, Xi’an 710069, P.
R. China, for their help with combustion calorimetric measurement.
This work was supported by Defence Science and Technology Project
(ProjectJSJL2015212A001).
where P is the detonation pressure (GPa), D is the deto-
nation velocity (km s-1), N is the moles of gaseous deto-
nation products per gram explosive (mol/g), Mg is average
mass of gaseous products (g/mol), and Qd is chemical
energy of detonation (cal/g). The values of D and P are
7.31 km s-1, 23.61 GPa, respectively.
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