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564 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

Hexyl seriously attacks the skin. First it dyes it yellow, then a serious eczema

appears, with blisters often reminiscent of those caused by burns. Air-borne dust

of the product may cause severe irritation of the mucous membranes and of the

respiratory tract. Workers exposed to the action of large quantities of hexyl should

be protected from inhaling its dust and from contact of the latter with the skin,

by good ventilation and protective masks and clothing. The toxicity of hexyl is

much higher than that of TNT (p. 161).

EXPLOSIVE PROPERTIES

Hexyl is a chemically stable compound. As van Duin and van Lennep [26]

found it can withstand 30 days’ heating at 95°C. They also determined its initiation

temperature as being 250°C when heated at a rate of 5°/min.

Its sensitivity to impact is lower then that of tetryl but somewhat higher than

that of picric acid. Kast [27] found that picric acid is exploded by a 2 kg weight

falling from 60 cm, while tetryl and hexyl are exploded by fall from 40 cm.

With a 10 kg falling weight picric acid exploded at the 20 cm height, hexyl at

10 cm and tetryl at 8 cm.

Salts of hexyl, in particular those formed with heavy metals, are more sensitive

to impact and friction than hexyl itself. They are inflammable and can be ignited

by a flame. The ammonium salt is an exception here, being the least sensitive and

not ignited by the flame, behaving like hexyl itself.

Haussermann [22] pointed out that hexyl is a more powerful explosive than TNT.

Further investigations yielded the following data on the explosive properties of

the substance (Kast [27]):

heat of explosion 1035 kcal/kg

volume of gases, V 0 675 I./kg

temperature, t 3450°C

specific pressure, f 9545 m

According to Kast, the heat of formation is negative and amounts to -4.6

kcal/kg (dHf = +4.6 kcal/kg).

For rate of detonation the following figures have been reported:

at a density of 1.58 g/cm^3 6900 m/sec (J. Marshall [28])

,, ,, ,, ,, 1.64 ,,^7100 ,, (Kast [27])

,, ,, ,, ,, 1.67 ,, 7150 ,, (J. Marshall [28])

The lead block expansion given by hexyl is 325-350 cm^3 - larger than that

caused by picric acid.

Hexyl can be brought to detonation as easily as tetryl, or even more easily.

For example, J. Marshall [28] has determined the minimum quantities of fulminate

of mercury and potassium chlorate mixtures (90:10), required for detonation of:

hexyl 0.18 g

tetry1 0.20 ,,

TNT 0.25 ,,