Liquid Explosive Mixtures - Liquid Explosives - page 300

Table 7.2 Detonation velocity of nitromethane [ 1 , 32 ]
Tube parameter v D /ms − 1 Booster Measurement

method

Material External

diameter/mm

Internal
diameter/mm

Copper 20 18 No. 8 detonator

and (1

6,190 Blasting fuse

5) g CE

-

Copper 25 23 Same as above 6,270 Same as

above

Steel 27 22 Same as above 6,360 Same as

above

Copper 20 18 No. 8 detonator

and 6.2 g CE

6,405 Electronic

timer

Nitromethane is usually not sensitive to heat or mechanical impact, exhibiting
stability to some extent. The starting materials for the production of nitromethane
are adequately abundant and inexpensive, and nitromethane itself is a noncorrosive
chemical that can be safely transported or handled, thus, it is an important com-
ponent for the preparation of liquid explosives.
The major hurdle to directly use pure nitromethane as liquid explosives is that its
detonating sensitivity is too low. Consequently, a large number of researchers have
devoted enormous efforts to the integrated and comprehensive studies aiming to
solve this problem. As a result, it was found that adding other liquids into nitro-
methane can produce a wide variety of liquid explosive mixtures.

7.1.1.1 Explosion Characteristics for the Mixture of Nitromethane
and Aromatics, Alcohols and Esters

To decrease the detonation sensitivity of nitromethane, higher nitroalkanes, ben-
zene, xylene, n-butanol, methanol, n-butyl acetate, amyl acetate, di-butyl phthalate,
di-butyl sebacate, and other substances can be added. However, when the amount of
additives reaches certain degree, detonation waves cannot be transmitted steadily.

7.1.1.2 Explosion Properties of Nitromethane with Basic Additives

Adding aniline, ethylenediamine, morpholine, methylamine, NH 4 OH, KOH,
Na 2 CO 3 , formic acid, nitric acid, sulfuric acid, phosphoric acid, and other substances
into nitromethane can increase its detonation sensitivity [ 33 ]. Speci

cally, acids can
act as weak sensitizer whereas basic substances are strong sensitizer. As a matter of
fact, adding a suitable base into nitromethane can enable its detonation with no. 8
detonator, especially after ethylenediamine has been added. Table 7.3 showed the
effect of ethylenediamine content on the detonation sensitivity of nitromethane.