C4 or Composition C4 is a common variety of military plastic explosive.

C4 is made up of explosive, binder, plasticizer and (lately) marker or taggant chemicals, such as 2, 3-dimethyl-2, 3-dinitrobutane (DMDNB) to help detect the explosive and identify its source. As in many plastic explosives the explosive material in C4 is RDX (Cyclonite, cyclotrimethylene trinitramine) which makes up around 91% of the C4 by weight. The plasticizer is di(2-ethylhexyl) or dioctyl sebacate (5.3%), the binder is polyisobutylene (2.1%). Another binder used is dioctyl adipate (DOA). A small amount of petroleum oil (1.6%) is also added.

C4 is made by combining the RDX slurry with the binder dissolved in a solvent. The solvent is then removed and the mixture is dried and filtered. The final material is an off-white solid with the feel of soft clay.

C4 is a development of a World War 2 material that mixed RDX with mineral oil and lecithin to achieve roughly the characteristics of plastic explosive but with certain disadvantages. C4 is part of a group of explosives along with C, C2 and C3, each containing different amounts of RDX developed in the 1960s. It can reportedly be shot upon or even thrown into a fire without detonating.

The C is sometimes said to stand for composition and the name is an abbreviation of Composition 4. However, composition is used for any stable explosive and composition A and composition B are also known variants. Therefore correctly C4 is Composition C4.

External links

• HowStuffWorks article