The Chemistry of Powder and Explosives - Sciencemadness Dot Org

NJTROSTARCH 275
the contents of the nitrato? was drowned in a small tub of water.
The product was purified entirely by cold-water washings, without
boiling. Ammonia was used to neutralize the acidity during
the preliminary washing, and it is probable that this use of
ammonia determined the stability of the product, perhaps because
ammonia was preferentially adsorbed, instead of acid, by
the material of the nitrostarch granules. The product was dried
at 35-10°.
Nitrostarch gives no color with iodine. It is insoluble in water
and does not gelatinize to form a paste as starch does when it is
boiled with water. It is not notably hygroscopic, but may take
up 1 or 2% of moisture from a damp atmosphere. It is soluble in
acetone. The varieties of nitrostarch which are soluble in etheralcohol
contain about the same amounts of nitrogen as the varieties
of nitrocellulose which dissolve in that mixed solvent.
Nitrostarch does not form a good film or tough colloid as nitrocellulose
does.
During the first World War a Trojan explosive which contained
nitrostarch was used in trench mortar shells and in hand
and rifle grenades. 106 Its composition was as follows.
Nitrostarch
Ammonium nitrate
Sodium nitrate
Charcoal
Heavy hydrocarbons
Anti-acid
Diphenylamine
Moisture
NOT LESS THAN NOT MORE THAN
23 0%
310
360
15
05
05
0.2
27 0%
35 0
40 0
25
15
1.5
04
12
All the dope materials were first ground to the desired fineness
and dried, and then turned over in a large mixing barrel while
the dry nitrostarch was added. Trench mortar shells were loaded
by stemming, but the explosive was jarred into the grenades
through small funnel-shaped openings Another nitrostarch explosive,
which was used only in grenades, was called Grenite and
consisted almost entirely of nitrostarch (about 97%) with small
amounts (about 1.5% each) of petroleum oil and of gum arabic.
It was made by spraying the dry materials with a solution of the
106 U. S. War Department Technical Manual TM 9-2900, p 109