urbaf2

(^466) CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES
THERMOCHEMICAL AND EXPLOSIVE PROPERTIES
OF CHLORONITROBENZENES
Desvergnes has tested the explosive properties of 1-chloro-2,4-dinitrobenzene
in a manometric bomb. At a density of 0.25, on comparison with other dinitro
compounds, he obtained pressures:
for chlorodinitrobenzene 2016 kg/cm^2
for chlorodinitrophenol 2084 ,,
for dinitrobenzene^2194 ,,
It can be seen from the above that the explosive properties of chlorodinitrobenzene
are slightly inferior to those of dinitrobenzene.
Experiments with chlorodinitrobenzene in mixture with picric acid for filling
shells have given no satisfactory results.
NITRO DERIVATIVES OF p- DICHLOROBENZENE
In the explosives industry only the nitro derivatives of p-dichlorobenzene and
1,3,5-trichlorobenzene have gained any importance.
p- Dichlorobenzene is the most important of the dichlorobenzene isomers,
being the principal product in the chlorination of benzene. Other isomers are formed
in smaller quantities.
Mono- and di-nitro derivatives were first obtained by Jungfleisch [9] in 1868.
Kijrner [36] demonstrated that the product of dinitration of p- dichlorobenzene
consists of the α− and β− isomers. Morgan and Norman [37] isolated yet another
one, the γ− isomer. The preparation and properties of all these isomers were in-
vestigated by Holleman [38].
Towards the end of World War I p- dichlorodinitrobenzene was used in the U.S.A
for shell filling under the name of “Parazol”. When brought to explosion it produced
an irritating gas, because of the large quantity of chlorine in the molecule. This
was probably the reason why it was used as an explosive, as its power was relatively
poor.
Mononitro derivatives of p- dichlorobenzene
1,4-Dichloro-2-nitrobenzene (m. p. 55°C; b. p. 267°C) was obtained by Jung-
fleisch by the nitration of p- dichlorobenzene.
A product of higher purity was isolated by Beilstein and Kurbatov [39] from
the products of chlorination of nitrobenzene in the presence of antimonium chloride