Plastic explosive

C-4 plastic explosive — the off-white rectangular blocks — being used to destroy unexploded artillery components. french-tip manicure verifies standard operating procedures are in use.

"Plastique" redirects here. For other uses, see Plastique (disambiguation).

Plastic explosive (or plastique) is a specialised form of explosive material. It is soft and hand moldable solid material. Plastic explosives are properly known as Putty explosives within the field of explosives engineering.

Common plastic explosives include Semtex and C-4. Plastic explosives are especially suited for explosive demolition as they can be easily formed into the best shapes for cutting structural members, and have a high enough velocity of detonation and density for metal cutting work. They are generally not used for ordinary blasting as they tend to be significantly more expensive than other materials that perform just as well in that field. Also, when an explosive is combined with a plasticizer, its power is generally lower than when it is pure.

History

The first plastic explosive was Gelignite, invented by Alfred Nobel in 1875.

Just prior to World War One, the British explosives chemist Oswald Silberrad obtained British and US patents for a series of plastic explosives called "Nitrols", composed of nitrated aromatics, collodion, and oxidising inorganic salts. The language of the patents indicate that at this time, Silberrad saw no need to explain to "those versed in the art" either what he meant by plasticity nor why it may be advantageous, as he only explains why his plastic explosive is superior to others of that type.

One of the simplest plastic explosives was Nobel’s Explosive No. 808, also known as Nobel 808 (often just called Explosive 808 in the British Armed Forces during the Second World War), developed by the British company Nobel Chemicals Ltd well before World War II. It had the appearance of green plasticine with a distinctive smell of almonds. During World War II it was extensively used by the British Special Operations Executive (SOE) for sabotage missions. It is also the explosive used in HESH anti-tank shells.

During and just after World War II a number of new RDX-based explosives were developed, including Compositions C, C2, and eventually C3. Together with RDX these incorporate various plasticisers to decrease sensitivity and make the composition plastic.

The origin of the obsolete term plastique dates back to the Nobel 808 explosive introduced to the US by the British in 1940. The samples of explosive brought to the USA by the Tizard Mission had already been packaged by the SOE ready for dropping to the French Resistance and were therefore labelled in French, as Explosif Plastique. It is still referred to by this name in France, and also by a few Americans. However, most English-speaking users refer to it either by the actual label printed on the packaging (e.g. C-4 or Semtex) or as plastic explosive.

C3 was effective but proved to be too brittle in cold weather. In the 1960s it was replaced by C-4, also using RDX but with polyisobutylene and di(2-ethylhexyl)sebacate as the binder and plasticizer.

Semtex was also developed in the 1960s by Stanislav Brebera by mixing of RDX with PETN and then adding binders and stabilizers.

List of plastic explosives

• Austria: KNAUERIT
• Czech Republic: Semtex
• Finland: PENO
• France: PE4, PLASTRITE (FORMEX P 1)
• Germany: Sprengkörper DM12, (Sprengmasse, formbar)
• Greece: C3, C4
• Italy: T-4 Plastico
• Poland: PWM, NITROLIT
• Russia: PW-5A Plastic Explosive
• Slovakia: CHEMEX (C4), TVAREX 4A
• Sweden: Sprängdeg m/46
• Switzerland: PLASTITE produced by SSE
• USA: C-4 (Composition C-4)
• United Kingdom: PE4, DEMEX
• Yugoslavia/Serbia: PP–01 (C4)

Usage

Plastic explosive is commonly used by engineers and combat engineers. The most common commercial use of plastic explosives is for shock hardening high manganese percentage steel. This material is typically used for train rail components and earth digging implements.

Some terrorist groups have also used plastic explosives, especially Semtex and C-4. In October 2000, terrorists used C-4 to attack the U.S.S. Cole, killing 17 sailors In 1996, terrorists used C-4 to blow up the Khobar Towers U.S. military housing complex in Saudi Arabia.