Non-initiating High Explosives
Chemistry of Powder and Explosives
by Tenny L Davis, Tenney Lombard Davis
This group includes a great number of organic and inorganic compounds. Only a relative minority are in practical use due to the difficult requirements involved with their stability, non-volatility, availability, expense and useful characteristics as an explosive.
Ammonium nitrate is a primary inorganic high explosive of importance. It is both stable and insensitive, it is one of the safest known explosives to handle. Used mainly as an ingredient in dynamite, propellants and bursting caps.
Nitroglycerin, but more correctly glyceryl trinitrate is a colorless liquid with great explosive potential made by nitrating glycerin. It will burn without actually exploding when it is in small quantity and unconfined. However, in high quantity or when confined, ignition results in detonation. Impact or friction easily detonates it so it is dangerous to transport and is seldom used by itself for that reason. Its primary use is as an ingredient in dynamites and propellants. Nitroglycerin was first introduced in 1847 but no practical use for it was known until Alfred Nobel made dynamite with it.
Nitrocellulose, also cellulose nitrate, is a fibrous white solid created from nitrating cellulose with nitric and sulfuric acids. The cellulose is commonly derived from cotton fiber and wood pulp. Highly explosive grades are called guncotton. It is very sensitive and detonates when great force is exhibited. This substance is used as an ingredient in the gelatin dynamites and smokeless powder.
Nitrostarch, or starch nitrate is characteristically similar to nitrocellulose. It is produced by nitrating starch and used primarily as an ingredient of blasting compositions.
Pentaerythritol tetranitrate, or commonly known as PETN, is produced from reacting formaldehyde and acetaldehyde to form pentaerythritole, which is then nitrated. The mass scale production of PETN was made possible because of the development of formaldehyde and acetaldehyde as cheap commercial chemicals following World War I. It was used extensively in World War II as an ingredient in bursting charges. Its use declined due to it being more unstable than other compositions. PETN is highly sensitive to impact and detonates with incredible force. Its brisance, that is, the shattering power of a high explosive) is greater than that of nitroglycerin.
Cyclotrimethylenetrinitramine, or Cyclonite, is produced by nitrating hexamethylenetetramine with concentrated nitric acid. Cyclonite, in comparison to PETN is about equal in brisance and a bit more powerful in its explosive force. Considerably more stable than PETN and used widely by the military during and after World War II as a base charge for detonators and utilized as an ingredient of bursting composition for bombs and shells.
2,4,6-Trinitrotoluene, or TNT remains one of the most important explosives in modern time. It is produced by nitrating toluene, typically in three stages. It is relatively insensitive and very stable, so much that TNT can be handled and stored with very little danger. It can be used by itself as a bursting charge in devices used by the military and likewise as an ingredient in explosive compositions.
Picric acid was introduced in 1771 and first used as a yellow dye. Around 1885 it was used in producing bursting charge for shells, and was to become the first modern high explosive used for this purpose. Though displaced by TNT, it was the primary explosive used by military up to around 1900. It is still used to a limited extent in fuse detonation and as an ingredient in pyrotechnic compositions. Picric acid is produced from nitrating phenol.