- Primary and secondary explosives
Primary and secondary are the two distinct classifications of
A primary explosive is an
explosivethat is extremely sensitive to stimuli such as impact, friction, heat, or electrostaticsources of initiation. Two examples are lead azideand lead styphnate. They are often used in detonators or to triggerlarger charges of less sensitive secondary explosives.
A secondary explosive is less sensitive and is therefore usable in a wider variety of applications. Examples of secondary explosives include TNT and
As a very general rule, primary explosives are considered to be those compounds that are more sensitive than
PETN. As a practical measure, primary explosives are sufficiently sensitive that they can be reliably initiated with a blow from a hammer; however, PETN can usually be initiated in this manner, so this is only a very broad guideline. Additionally, several compounds, such as nitrogen triiodide, are so sensitive that they cannot even be handled without detonating.
A number of primary explosives are commonly used in
blasting caps to translate a signal (electrical, shock, or in the case of laser detonation systems, light) into an action, i.e., an explosion. A small quantity—usually milligrams—is sufficient to initiate a larger charge of explosive that is usually safer to handle.
Primary explosives include:
Hexamethylene triperoxide diamine
Lead azide[ [http://www.powerlabs.org/chemlabs/lead_picrate.htm PowerLabs Lead Picrate Synthesis ] ]
Tetramine Copper complexes
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