The Chemistry of Powder and Explosives - Sciencemadness Dot Org

154 AROMATIC NITRO COMPOUNDS
groups is so considerable that the introduction of the third nitro
group may be accomplished without the use of fuming sulfuric
acid. Pure TNX, large almost colorless needles from benzene,
melts at 182.3°.
Trinitroxylene is not powerful enough for use alone as a high
explosive, and it does not always communicate an initial detonation
throughout its mass. It is used in commercial dynamites, for
which purpose it does not require to be purified and may contain
an oily mixture of isomers and other nitrated xylenes. Its large
excess of carbon suggests that it may be used advantageously in
conjunction with an oxidizing agent. A mixture of 23 parts of
TNX and 77 parts of ammonium nitrate, ground intimately together
in a black powder mill, has been used in high-explosive
shells. It was loaded by compression. Mixtures, about half and
half, of TNX with TNT and with picric acid are semi-solid when
warm and can be loaded by pouring. The eutectic of TNX and
TNT contains between 6 and 7 per cent of TNX and freezes at
73.5°. It is substantially as good an explosive as TNT. A mixture
of 10 parts TNX, 40 parts TNT, and 50 parts picric acid can be
melted readily under water. In explosives such as these the TNX
helps by lowering the melting point, but it also attenuates the
power of the more powerful high explosives with which it is
mixed. On the other hand, these mixtures take advantage of the
explosive power of TNX, such as that power is, and are themselves
sufficiently powerful and satisfactory for many purposes—
while making use of a raw material, namely m-xylene, which is
not otherwise applicable for use in the manufacture of military
explosives.
Nitro Derivatives of Naphthalene
Naphthalene nitrates more readily than benzene, the first nitro
group taking the a-position which is ortho on one nucleus to the
side chain which the other nucleus constitutes. The second nitro
group takes one or another of the expected positions, either the
position meta to the nitro group already present or one of the
a-positions of the unsubstituted nucleus. The dinitration of
naphthalene in actual practice thus produces a mixture which
consists almost entirely of three isomers. Ten different isomeric
dinitronaphthalenes are possible, seven of which are derived from
a-nitronaphthalene, seven from /3-nitronaphthalene, and four