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NITRO DERIVATIVES OF HIGHER BENZENE HOMOLOGUES

Its hexanitro derivative: 2,4,6,2’,4’,6’-hexanitrodiphenyl

417

m. p. 238°C

has evoked much more interest as an explosive.

The compound may be obtained by Ullmann and Bielecki’s [37] method, which

consists in heating picryl chloride with copper powder in a high boiling solvent

like nitrobenzene, toluene or xylene.

Its explosive power is higher than that of hexanitro-diphenylamine (hexyl)

by nearly 10%. According to a patent granted to Sprengstoff A. G. Carbonit

[38] the lead block test figure for the product is about 360 cm^3. The initia-

tion temperature of the explosive is high - over 320°C. It has also the advantage

of being only slightly toxic (less than hexyl). On the other hand its application

is limited by the cost of manufacture, which requires picryl chloride. Because of

its high melting point it cannot be used in the molten state. So it should either be

compressed or used as an additive in fusible mixtures with other nitro compounds.

NITRATION OF MIXTURES

During World War II a method of preparing mixtures of nitro compounds

(e.g. TNT and TNX, or TNT and tetryl, see Vol. IV) was developed by the Ger-

mans. It consisted in the nitration of the corresponding lower nitrated compounds,

namely a mixture of mononitrotoluenes plus mononitroxylenes was nitrated in

two stages to form trinitro compounds. In this way a product containing 20%

of TNX and 80% of TNT was obtained.

A mixture consisting of 45 parts of TNX and 50 parts of tetryl was prepared

by mixing mononitroxylenes and dinitromethylaniline in suitable proportions and

nitrating them. To the nitration product TNT was added in such a quantity as to

obtain a mixture composed of 45% of trinitroxylene, 50% of tetryl and 5% of TNT.

The mixture melts at 80°C; it does not need washing with a sodium bicarbonate

solution, as is the case with TNT. A simple washing with hot water will suffice.

The mixture has proved to be a fully adequate substitute for TNT.

NITRO DERIVATIVES OF POLYMERS

During World War II a large amount of research was carried out in seeking
fully synthetic polymeric materials which could substitute a semi-synthetic polymer

such as nitrocellulose. This research was connected with the immense development

of plastics chemistry, which began shortly before World War II and is still advancing

at a great pace.