A
pyrotechnic composition is a substance or mixture of substances designed to produce an effect by heat, light, sound, gas or smoke or a combination of these, as a result of non-detonative self-sustaining
exothermicAn exothermic reaction is a chemical reaction that releases energy in the form of light or heat. It is the opposite of an endothermic reaction. Expressed in a chemical equation:-Overview:...
chemical reactions. Pyrotechnic substances do not rely on oxygen from external sources to sustain the reaction.
Basic types of pyrotechnic compositions are:
- flash powder
Flash powder is a pyrotechnic composition, a mixture of oxidizer and metallic fuel, which burns quickly and if confined produces a loud report. It is widely used in theatrical pyrotechnics and fireworks and was once used for flashes in photography.Different varieties of flash powder are made from...
– burns very fast, produces explosions and/or bright flashes of light
- gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...
– burns slower than flash powder, produces large amount of gases
- solid propellant
A propellant is a material that produces pressurized gas that:* can be directed through a nozzle, thereby producing thrust ;...
s – produce large amount of hot gases, used as sources of kinetic energy for rockets and projectiles
- pyrotechnic initiator
A pyrotechnic initiator is a device containing a pyrotechnic composition used primarily to ignite other, more difficult-to-ignite materials, e.g. thermites, gas generators, and solid-fuel rockets...
s – produce large amount of heat, flames, and/or hot sparks, used to ignite other compositions
- gas generator
A gas generator usually refers to a device, often similar to a solid rocket or a liquid rocket that burns to produce large volumes of relatively cool gas, instead of maximizing the temperature and specific impulse. The low temperature allows the gas to be put to use more easily in many...
s – produce large amount of gas, either high volume at short time (for actuators and ejection charges, often using solid propellants) or controlled flow rate (e.g. chemical oxygen generatorA chemical oxygen generator is a device releasing oxygen created by a chemical reaction. The oxygen source is usually an inorganic superoxide, chlorate, or perchlorate. A promising group of oxygen sources are ozonides. The generators are usually ignited mechanically, by a firing pin, and the...
s, often using thermite-like compositions)
- ejection charge
Ejection charge, also called expelling charge, is a pyrotechnic composition, a type of a pyrotechnic gas generator designed to produce a small short-term amount of thrust to burst open a container and eject its content....
s – burn fast, produce large amount of gas at short time, used to eject payloads from containers
- burst charge
In fireworks, a burst charge is an energetic pyrotechnic mixture placed in a shell which is ignited when the shell reaches the desired height in order to pass fire to and spread the stars. Burst charge compositions are usually coated onto rice hulls or other low-density fillers, which increases...
s – burn fast, produce large amount of gas at short time, used to fragment a container and eject its content
- smoke composition
A smoke composition is a pyrotechnic composition designed primarily to generate smoke. Smoke compositions are used as obscurants or for generation of signaling smokes. Some are used as a payload of smoke bombs and smoke grenades.-Obscurants:...
s – burn slowly, produce smokeSmoke is a collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires , but may also be used for pest...
, plain or coloredColored smoke is a kind of smoke created by an aerosol of small particles of a suitable pigment or dye.Colored smoke can be used for smoke signals, often in a military context. It can be produced by smoke grenades, or by various other pyrotechnical devices...
- delay composition
Delay composition, also called delay charge or delay train, is a pyrotechnic composition, a sort of pyrotechnic initiator, a mixture of oxidizer and fuel that burns in a slow, constant rate that should not be significantly dependent on temperature and pressure. Delay compositions are used to...
s – burn at constant slow speed, used to introduce delays into the firing train
- pyrotechnic heat source
A pyrotechnic heat source, also called heat pellet, is a pyrotechnic device based on a pyrotechnic composition with a suitable igniter. Its role is to produce controlled amount of heat...
s – produce large amount of heat and little to no gases, slow-burning, often thermite-like compositions
- sparkler
A sparkler is a type of hand-held firework that burns slowly while emitting colored flames, sparks, and other effects.In the United Kingdom, a sparkler is often used by children at bonfire and fireworks displays on Guy Fawkes Night, the fifth of November, and in the United States on Independence...
s – producing white or colored sparks
- flares
A flare, also sometimes called a fusee, is a type of pyrotechnic that produces a brilliant light or intense heat without an explosion. Flares are used for signalling, illumination, or defensive countermeasures in civilian and military applications...
– burn slowly, produce high amount of light, used for illumination or signaling
- coloured fireworks
Fireworks are a class of explosive pyrotechnic devices used for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display. A fireworks event is a display of the effects produced by firework devices...
compositions – produce light, white or colored
Some pyrotechnic compositions are used in industry and
aerospaceAerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...
for generation of large volumes of gas in
gas generatorA gas generator usually refers to a device, often similar to a solid rocket or a liquid rocket that burns to produce large volumes of relatively cool gas, instead of maximizing the temperature and specific impulse. The low temperature allows the gas to be put to use more easily in many...
s (e.g. in
airbagAn Airbag is a vehicle safety device. It is an occupant restraint consisting of a flexible envelope designed to inflate rapidly during an automobile collision, to prevent occupants from striking interior objects such as the steering wheel or a window...
s), in
pyrotechnic fastenerA pyrotechnic fastener is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt are typically activated by an electric current, and the charge breaks the bolt into two or more pieces...
s, and in other similar applications. They are also used in military pyrotechnics, when production of large amount of noise, light, or infrared radiation is required; eg.
missile decoy flaresA flare is an aerial infrared countermeasure to counter an infrared homing surface-to-air missile or air-to-air missile. Flares are commonly composed of a pyrotechnic composition based on magnesium or another hot-burning metal, with burning temperature equal to or hotter than engine exhaust...
,
flash powderFlash powder is a pyrotechnic composition, a mixture of oxidizer and metallic fuel, which burns quickly and if confined produces a loud report. It is widely used in theatrical pyrotechnics and fireworks and was once used for flashes in photography.Different varieties of flash powder are made from...
s, and
stun grenadeA stun grenade, also known as a flash grenade or a flashbang, is a non-lethal weapon. The first devices like this were created in the 1960s at the order of the British Special Air Service as an incapacitant....
s. A new class of
reactive materialIn the US military, reactive materials are a new class of materials currently being investigated by the Office of Naval Research and others as a means to increase the lethality of direct-hit or fragmentation warheads...
compositions is now under investigation by military.
Many pyrotechnic compositions – especially involving aluminium and perchlorates – are often highly sensitive to friction, impact, and
static electricityStatic electricity refers to the build-up of electric charge on the surface of objects. The static charges remain on an object until they either bleed off to ground or are quickly neutralized by a discharge. Static electricity can be contrasted with current electricity, which can be delivered...
. Even as little as 0.1–10 millijoules spark can set off certain mixtures.
Materials used
Pyrotechnic compositions are usually homogenized mixtures of small particles of fuels and oxidizers. The particles can be grains or flakes. Generally, the higher the surface area of the particles, the higher the reaction rate and burning speed. For some purposes, binders are used to turn the powder into a solid material.
Fuels
Typical fuels are based on metal or
metalloidMetalloid is a term used in chemistry when classifying the chemical elements. On the basis of their general physical and chemical properties, each element can usually be classified as a metal or a nonmetal. However, some elements with intermediate or mixed properties can be harder to characterize...
powders. A flash powder composition may specify multiple different fuels. Some fuels can also serve as binders. Common fuels include:
- Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
s
- Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
– most common fuel in many classes of mixtures, also a combustion instability suppressant. Less energy per mass than carbon but less gas evolution, retaining heat in the reaction mixture. High-temperature flame with solid particles, which interfere with flame colorants. Reacts with nitrates, except ammonium nitrate, yielding nitrogen oxides, ammonia, and heat (the reaction is slow at room temperature but violent at above 80 °C and may spontaneously ignite); the reaction can be inhibited by a weak acid, e.g. boric acidBoric acid, also called hydrogen borate or boracic acid or orthoboric acid or acidum boricum, is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a...
. Corroded by alkaline substances. Flake particles easier to ignite and better for pyrotechnics than spherical ones. In presence of moisture reacts with potassium chlorate and perchlorate, yielding hydrogen. Particle size selected according to the required burn rate.
- Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...
– more sensitive and violent than aluminium, increases probability of spontaneous ignition in storage. Used in fireworks to increase flame temperature. Less interference with flame color than aluminium.
- Magnalium
Magnalium is an aluminium alloy with 1.5 to 2% magnesium and small amounts of copper, nickel, and tin. Some alloys, intended for particular uses at the cost of poor corrosion resistance, may consist of up to 50% magnesium...
– aluminium-magnesium alloy, more stable and less expensive than magnesium; less reactive than magnesium, easier to ignite than aluminium
- Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
– makes gold sparks, frequently used
- Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
– an alloy of iron and carbon, makes branching yellow-orange sparks
- Zirconium
Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium...
– produces hot particles, good for ignition mixtures, eg. the NASA Standard Initiator, also a combustion instability suppressant
- Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....
– produces hot particles, increases sensitivity to impact and friction; sometimes the Ti4Al6V alloy is used which gives a bit brighter white sparks; together with potassium perchlorate it is used in some pyrotechnic igniters; coarse powder produces beautiful branching blue-white sparks
- Ferrotitanium
Ferrotitanium is a ferroalloy, an alloy of iron and titanium with between 10-20..45-75 % titanium and sometimes a small amount of carbon. It is used in steelmaking as a cleansing agent for iron and steel; the titanium is highly reactive with sulfur, carbon, oxygen, and nitrogen, forming insoluble...
– iron-titanium alloy, produces bright yellow-white sparks, used in pyrotechnic stars, rockets, comets, and fountains
- Ferrosilicon
Ferrosilicon, or ferrosilicium, is a ferroalloy, an alloy of iron and silicon with between 15% and 90% silicon. It contains a high proportion of iron silicides. Its melting point is about 1200 °C to 1250 °C with a boiling point of 2355 °C...
– iron-silicon alloy, used in some mixtures, sometimes replacement of calcium silicide
- Manganese
Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
– used to control burn rates, e.g. in delay compositions
- Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
– used in some smoke compositionA smoke composition is a pyrotechnic composition designed primarily to generate smoke. Smoke compositions are used as obscurants or for generation of signaling smokes. Some are used as a payload of smoke bombs and smoke grenades.-Obscurants:...
s, together with sulfur used in some early amateur rocket fuels, also in pyrotechnic stars; heavy, zinc-based compositions may require additional lift to fly high enough; moisture-sensitive; can spontaneously ignite; rarely used as primary fuel except in smoke compositions, can be encountered as a secondary enhancement fuel
- Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
– used as a blue colorant with other fuels
- Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
– a zinc-copper alloy used in some fireworks formulas, as a blue colorant for its copper content
- Tungsten
Tungsten , also known as wolfram , is a chemical element with the chemical symbol W and atomic number 74.A hard, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth only in chemical compounds. It was identified as a new element in 1781, and first isolated as...
– used to control and slow down burn rates of compositions, also in delay compositions
- Zirconium-nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
alloy – used in some military delay compositions
- Metal hydrides (lower heat of combustion
The heat of combustion is the energy released as heat when a compound undergoes complete combustion with oxygen under standard conditions. The chemical reaction is typically a hydrocarbon reacting with oxygen to form carbon dioxide, water and heat...
than pure metals, but increased sensitivity/reactivity to water):
- Titanium(II) hydride
Titanium hydride is a chemical compound of titanium and hydrogen, a hydride. It is highly reactive and needs to be kept away from heat and strong oxidizers....
– together with potassium perchlorate it is used in some igniters
- Zirconium(II) hydride
Zirconium hydride is a chemical compound, a hydride of zirconium. The commercial form is usually a flammable, gray-black powder.It is used in powder metallurgy, as a hydrogenation catalyst, and as a reducing agent, vacuum tube getter, and a foaming agent in production of metal foams...
– together with potassium perchlorate it is used in some igniters
- Aluminum hydride – unstable for storage (decomposes easily with humidity) and reacts dangerously in contact with water
- Decaborane
Decaborane, also called decaborane, is the borane with the chemical formula B10H14. This white crystalline compound is one of the principal boron hydride clusters, both as a reference structure and as a precursor to other boron hydrides....
– experimented with for some rocket fuels
- Metal carbides
- Zirconium carbide
Zirconium carbide is an extremely hard refractory ceramic material, commercially used in tool bits for cutting tools. It is usually processed by sintering. It has the appearance of a gray metallic powder with cubic crystal structure...
– used in some rocket fuels, also a combustion instability suppressant
- Metalloid
Metalloid is a term used in chemistry when classifying the chemical elements. On the basis of their general physical and chemical properties, each element can usually be classified as a metal or a nonmetal. However, some elements with intermediate or mixed properties can be harder to characterize...
s
- Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
– high flame temperature, burns producing molten glass, used in some ignition compositions and delay charges, commonly with lead tetroxide
- Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...
– used in some ignition mixtures
- Antimony
Antimony is a toxic chemical element with the symbol Sb and an atomic number of 51. A lustrous grey metalloid, it is found in nature mainly as the sulfide mineral stibnite...
– used in some fireworks for glitterGlitter describes an assortment of very small pieces of copolymer plastics, aluminum foil, titanium dioxide, iron oxides, bismuth oxychloride or other materials painted in metallic, neon and iridescent colors to reflect light in a sparkling spectrum...
effects, toxic, burns bright white; usually used as 200–300 mesh; with potassium nitrate and sulfur produces white fires
- Non-metallic inorganic
- Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
– ignition promoter, increases burn rate; increases sensitivity to temperature, impact and friction, dangerous in combination with chlorates; commonly used with nitrates; used as an additive; may contain residual acids, combination with carbonates or other alkaline stabilizers is advised in acid-sensitive compositions
- Red phosphorus – extremely dangerous, especially in combination with chlorates (Armstrong's mixture
Armstrong's mixture is a highly sensitive primary explosive. Its primary ingredients are red phosphorus and strong oxidizer, such as potassium chlorate and potassium perchlorate. Sulfur and calcium carbonate might be present in small amounts, though other additives are also used. Commercially,...
); used in capsA cap gun is a toy gun that creates a loud sound simulating a gunshot and a puff of smoke when the trigger is pulled. Cap guns were originally made of cast iron, but after World War II were made of zinc alloy, and most newer models are made of plastic....
; also used in matchA match is a tool for starting a fire under controlled conditions. A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface...
es and some military infrared flares; toxic
- White phosphorus – used in incendiary weapons and to make some military smoke screens, ignites spontaneously in air; even more toxic
- Calcium silicide
Calcium silicide , also called calcium disilicide, is an inorganic compound, a silicide of calcium. It is a whitish or dark grey to black solid matter with melting point 1033°C. It is insoluble in water, but may decompose when subjected to moisture, evolving hydrogen and producing calcium...
– used in some special compositions
- Antimony trisulfide – ignition promoter; fine powder increases sensitivity, sharpens the boom of salutes; toxic and sensitive to static electricity; emits bright white light, crystals also used as a fuel in glitter compositions and in white comets and pyrotechnic stars. Sensitive to friction and impact; the degree of sensitisation depends on the oxidizer (sensitive to friction and impact with potassium chlorate, friction with potassium perchlorate, impact with ammonium perchlorate, and insensitive to either with potassium nitrate).
- Arsenic sulfide
Arsenic sulfide may refer to:*Arsenic trisulfide, As2S3, the mineral orpiment*Tetraarsenic tetrasulfide, As4S4, the mineral realgar*Tetraarsenic trisulfide, As4S3, occurs as the minerals α- and β- dimorphite...
(realgarRealgar, α-As4S4, is an arsenic sulfide mineral, also known as "ruby sulphur" or "ruby of arsenic". It is a soft, sectile mineral occurring in monoclinic crystals, or in granular, compact, or powdery form, often in association with the related mineral, orpiment . It is orange-red in colour, melts...
) – toxic, sensitive to impact and friction. Used for report compositions due to its sensitivity with chlorate even in small amounts. Used in yellow smoke compositionA smoke composition is a pyrotechnic composition designed primarily to generate smoke. Smoke compositions are used as obscurants or for generation of signaling smokes. Some are used as a payload of smoke bombs and smoke grenades.-Obscurants:...
s due to its low boiling point.
- Phosphorus trisulfide – used to make match
A match is a tool for starting a fire under controlled conditions. A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface...
es
- Calcium phosphide
Calcium phosphide is a chemical is used in incendiary bombs. It has the appearance of red-brown crystalline powder or grey lumps, with melting point of 1600 °C. Its trade name is Photophor for the incendiary use or Polythanol for the use as rodenticide.It may be formed by reaction of the elements...
– liberates phosphinePhosphine is the compound with the chemical formula PH3. It is a colorless, flammable, toxic gas. Pure phosphine is odourless, but technical grade samples have a highly unpleasant odor like garlic or rotting fish, due to the presence of substituted phosphine and diphosphine...
when wet, used in some naval signal flareSignal Flare is the name of several fictional characters in the various Transformers universes.-Transformers: Energon:Signal Flare is a young Omnicon. Signal Flare is one of the greatest Energon welders of his kind. His Omnicon brothers depend greatly on his skills and experience...
s
- Potassium thiocyanate
Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides...
- Carbon-based
- Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
- Charcoal
Charcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...
– makes dim gold sparks
- Graphite
The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...
– also used as opacifierAn opacifier is a substance added to a material in order to make the ensuing system opaque. An example of a chemical opacifier is tin dioxide , which is used to opacify ceramic glazes and milk glass; bone ash is also used....
in rocket fuels to prevent heat transfer by radiation into lower layers of fuels and avoid the related explosions
- Carbon black
Carbon black is a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, ethylene cracking tar, and a small amount from vegetable oil. Carbon black is a form of amorphous carbon that has a high surface-area-to-volume ratio, although its...
– produces long lasting fine gold sparks in fireworks, also used as opacifier in rocket fuels
- Asphaltum – carbon-based fuel, also used as a binder. Some forms contain ammonia; should not be combined with chlorates.
- Wood flour
Wood flour is finely pulverized wood that has a consistency fairly equal to sand or sawdust, but can vary considerably, with particles ranging in size from a fine powder to roughly the size of a grain of rice. Most wood flour manufacturers are able to create batches of wood flour that have the...
- Organic chemicals
- Sodium benzoate
Sodium benzoate has the chemical formula NaC6H5CO2; it is a widely used food preservative, with E number E211. It is the sodium salt of benzoic acid and exists in this form when dissolved in water. It can be produced by reacting sodium hydroxide with benzoic acid.-Uses:Sodium benzoate is a...
– often used in whistle mixWhistle mix is a general term to refer to any pyrotechnic composition that emits a whistling sound when pressed into a tube and ignited. It is used as a rocket propellant, particularly in small bottle rockets...
es together with potassium perchlorate
- Sodium salicylate
Sodium salicylate is a sodium salt of salicylic acid. It can be prepared from sodium phenolate and carbon dioxide under higher temperature and pressure...
– used in some whistle mixes
- Gallic acid
Gallic acid is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4,5-trihydroxybenzoic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. The chemical formula is C6H23COOH. Gallic acid is found both free and as part of...
– used in some whistle mixes; sensitive to impact and friction, there are safer alternatives
- Potassium picrate
Potassium picrate, or potassium 2,4,6-trinitrophenolate, is an organic chemical, a picrate of potassium. It is a reddish yellow or green crystalline material. It is a primary explosive...
– used in some whistle compositions, safer than gallic acid but still dangerous, with heavy metals (e.g. lead) forms explosive salts
- Terephthalic acid
Terephthalic acid is the organic compound with formula C6H42. This colourless solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several billion kilograms are produced annually...
– a fuel in some smoke compositions
- Hexamine
Hexamethylenetetramine is a heterocyclic organic compound with the formula 6N4. This white crystalline compound is highly soluble in water and polar organic solvents. It has a cage-like structure similar to adamantane. It is useful in the synthesis of other chemical compounds, e.g. plastics,...
– a low-reactivity, accessory fuel
- Anthracene
Anthracene is a solid polycyclic aromatic hydrocarbon consisting of three fused benzene rings. It is a component of coal-tar. Anthracene is used in the production of the red dye alizarin and other dyes...
– a fuel in some smoke compositions, produces black smoke
- Naphthalene
Naphthalene is an organic compound with formula . It is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings...
– a fuel in some smoke compositions
- Lactose
Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk , although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from or , the Latin word for milk,...
– used together with potassium chlorate in many smoke compositions; cheap low-reactivity accessory fuel
- Dextrose – used in some amateur solid rocket fuels
- Sucrose
Sucrose is the organic compound commonly known as table sugar and sometimes called saccharose. A white, odorless, crystalline powder with a sweet taste, it is best known for its role in human nutrition. The molecule is a disaccharide composed of glucose and fructose with the molecular formula...
– used in some smoke compositions
- Sorbitol
Sorbitol, also known as glucitol, Sorbogem® and Sorbo®, is a sugar alcohol that the human body metabolizes slowly. It can be obtained by reduction of glucose, changing the aldehyde group to a hydroxyl group. Sorbitol is found in apples, pears, peaches, and prunes...
– used together with potassium nitrate as an amateur solid rocket fuel
- Dextrin
Dextrins are a group of low-molecular-weight carbohydrates produced by the hydrolysis of starch or glycogen. Dextrins are mixtures of polymers of D-glucose units linked by α- or α- glycosidic bonds....
– also a binder
- Stearin
Stearin , or tristearin, or glyceryl tristearate is a triglyceride, a glyceryl ester of stearic acid, derived from animal fats created as a byproduct of processing beef. It can also be found in tropical plants such as palm. It is used as tallow in the manufacture of candles and soap. In the...
, stearic acidStearic acid is the saturated fatty acid with an 18 carbon chain and has the IUPAC name octadecanoic acid. It is a waxy solid, and its chemical formula is CH316CO2H. Its name comes from the Greek word στέαρ "stéatos", which means tallow. The salts and esters of stearic acid are called stearates...
– accessory fuel, a possible replacement for charcoal and/or sulfur in some compositions; lengthens flames, can reduce friction sensitivity; phlegmatizing agent
- Hexachloroethane
Hexachloroethane, also known as perchloroethanes , C2Cl6, is a colorless solid at room temperature which is used by the US Military in smoke compositions, e.g...
– used in many military smoke compositions
- Organic polymers and resins, also sometimes serving as binders
- Teflon, Viton
Viton is a brand of synthetic rubber and fluoropolymer elastomer commonly used in O-rings and other molded or extruded goods. The name is a registered trademark of DuPont Performance Elastomers L.L.C.....
and other fluoropolymerA fluoropolymer is a fluorocarbon based polymer with multiple strong carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases.-History:Fluoropolymers were accidentally discovered in 1938 by Dr. Roy J...
s – sometimes also working as oxidizer – used in military pyrolantPyrolant, from the Greek word pyros to describe energetic materials that generate hot flames upon combustion. Pyrolants are metal-based pyrotechnic compositions containing virtually any oxidizer....
compositions, eg. Magnesium/Teflon/VitonMagnesium/Teflon/Viton is a pyrolant. Teflon and Viton are trademarks of DuPont for polytetrafluoroethylene, n, and vinylidenfluoride-hexafluoroisopropene-copolymer, nn.-History:...
; extremely reactive in contact with some fine metal powders
- Hydroxyl-terminated polybutadiene
Hydroxyl-terminated polybutadiene is a polymer of butadiene terminated at each end with a hydroxyl functional group. It reacts with diisocyanate to form polyurethane, a stable and easily stored synthetic material....
(HTPB), used together with aluminium and ammonium nitrate in composite rocket fuels as a fuel and binder
- Carboxyl-terminated polybutadiene (CTPB), used in composite rocket fuels as a fuel and binder
- PBAN
Polybutadiene acrylonitrile copolymer, also noted as polybutadiene — acrylic acid — acrylonitrile terpolymer.This was the binder formulation widely used on the 1960-70's big boosters...
, used together with aluminium and ammonium nitrate in composite rocket fuels as a fuel and binder
- Polysulfide
Polysulfides are a class of chemical compounds containing chains of sulfur atoms. There are two main classes of polysulfides: anions and organic polysulfides. Anions have the general formula Sn2−. These anions are the conjugate bases of the hydrogen polysulfides H2nSn...
, used in composite rocket fuels as a fuel and binder
- Polyurethane
A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...
, used in composite rocket fuels as a fuel and binder
- Polyisobutylene
- Nitrocellulose
Nitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton...
- Polyethylene
Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...
- Polyvinyl chloride
Polyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...
, also serving as chlorine donor and a binder
- Polyvinylidene chloride
Polyvinylidene chloride is a polymer derived from vinylidene chloride.-History:Ralph Wiley, a Dow Chemical lab worker, accidentally discovered polyvinylidene chloride in 1933. While cleaning laboratory glassware, he came across a vial he could not scrub clean...
, also serving as chlorine donor
- Shellac
Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes , which are dissolved in ethyl alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish...
, good especially for colored flame compositions
- Accroides resin (red gum
Red Gum may refer to any of a number of species of Eucalyptus or the closely related Corymbia, including*Corymbia calophylla, Red Gum or Marri, native to Western Australia*Eucalyptus camaldulensis, Red Gum, Murray Red Gum or River Red Gum...
), higher burning rate than shellac, burns well even with potassium perchlorate. Suitable for chrysanthemum stars.
When metallic fuels are used, the metal particle size is important. A larger surface area to volume ratio leads to a faster reaction; this means that smaller particle sizes produce a faster-burning composition. The shape also matters. Spherical particles, like those produced by atomizing molten metal, are undesirable. Thin and flat particles, like those produced by milling metal foil, have higher reaction surface and therefore are ideal when faster reaction is desired. Using nanoparticles can drastically affect the reaction rates; metastable intermolecular composites exploit this.
A suitable metal fuel may be dangerous on its own, even before it is mixed with an oxidizer. Careful handling is required to avoid the production of pyrophoric metal powders.
Oxidizers
PerchloratePerchlorates are the salts derived from perchloric acid . They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat thyroid gland disorders. They are used extensively within the pyrotechnics industry, and ammonium perchlorate is also a...
s,
chlorateThe chlorate anion has the formula ClO. In this case, the chlorine atom is in the +5 oxidation state. "Chlorate" can also refer to chemical compounds containing this anion; chlorates are the salts of chloric acid. "Chlorate", when followed by a roman numeral in parentheses, e.g...
s and
nitrateThe nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
s are the most commonly used oxidizers for flash powders. Other possibilities include
permanganateA permanganate is the general name for a chemical compound containing the manganate ion, . Because manganese is in the +7 oxidation state, the permanganate ion is a strong oxidizing agent. The ion has tetrahedral geometry...
s,
chromateChromate salts contain the chromate anion, CrO42−. Dichromate salts contain the dichromate anion, Cr2O72−. They are oxyanions of chromium in the oxidation state +6. They are moderately strong oxidizing agents.- Chemical properties :...
s, and some
oxideAn oxide is a chemical compound that contains at least one oxygen atom in its chemical formula. Metal oxides typically contain an anion of oxygen in the oxidation state of −2....
s. Generally, the less the oxidizer, the slower the burning and the more light produced. For use at very high temperatures,
sulfateIn inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...
s can be used as oxidizers in combination with very strongly reducing fuels.
Oxidizers in use include:
- Perchlorate
Perchlorates are the salts derived from perchloric acid . They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat thyroid gland disorders. They are used extensively within the pyrotechnics industry, and ammonium perchlorate is also a...
s (also serving as chlorine donors):
- Potassium perchlorate
Potassium perchlorate is the inorganic salt with the chemical formula KClO4. Like other perchlorates, this salt is a strong oxidizer and potentially reacts with many organic substances...
– common, relatively stable. Almost non-hygroscopic. Low solubility in water. Produces high temperature flame and smoke of potassium chloride. Safer replacement of potassium chlorate. Impact-sensitive with phosphorus,
- Ammonium perchlorate
Ammonium perchlorate is an inorganic compound with the formula NH4ClO4. It is the salt of perchloric acid and ammonia. It is a powerful oxidizer, which is why its main use is in solid propellants...
– the most common oxidizer for modern solid rocket fuels; more sensitive to mechanical stimuli than potassium perchlorate. Uncommon in fireworks; creates hot flame, enhances barium, strontium and copper colorantsA pyrotechnic colorant is a chemical compound which causes a flame to burn with a particular color. These are used to create the colors in pyrotechnic compositions like fireworks and colored fires. The color-producing species are usually created from other chemicals during the reaction. Metal salts...
by acting as a chlorine donor. Reacts with magnesium when wet and liberates heat and ammonia, can self-ignite. In contact with potassium nitrate (e.g. in black powder) produces potassium perchlorate and hygroscopic ammonium nitrate; no such reaction with sodium nitrate. Reacts with potassium chlorate, producing unstable, gradually decomposing ammonium chlorateAmmonium chlorate is an inorganic compound with the formula NH4ClO3.It is obtained by neutralizing chloric acid with either ammonia or ammonium carbonate, or by precipitating barium, strontium or calcium chlorates with ammonium carbonate or ammonium sulfate, producing the respective carbonate or...
; such combination has to be avoided.
- Nitronium perchlorate
Nitronium perchlorate, NO2ClO4, also known as nitryl perchlorate and nitroxyl perchlorate, is an inorganic chemical, the salt of the perchlorate anion and the nitronium cation. It forms colorless monoclinic crystals. It is hygroscopic, and is a strong oxidizing and nitrating agent. It may become...
- Chlorate
The chlorate anion has the formula ClO. In this case, the chlorine atom is in the +5 oxidation state. "Chlorate" can also refer to chemical compounds containing this anion; chlorates are the salts of chloric acid. "Chlorate", when followed by a roman numeral in parentheses, e.g...
s (also serving as chlorine donors, incompatible with ammonium salts because of forming unstable explosive ammonium chlorateAmmonium chlorate is an inorganic compound with the formula NH4ClO3.It is obtained by neutralizing chloric acid with either ammonia or ammonium carbonate, or by precipitating barium, strontium or calcium chlorates with ammonium carbonate or ammonium sulfate, producing the respective carbonate or...
, incompatible with sulfur and other acidic chemicals because of production of spontaneously igniting chlorine dioxideChlorine dioxide is a chemical compound with the formula ClO2. This yellowish-green gas crystallizes as bright orange crystals at −59 °C. As one of several oxides of chlorine, it is a potent and useful oxidizing agent used in water treatment and in bleaching....
; very dangerous with phosphorus; should not be combined with hydrocarbon fuels/binders, e.g. asphalt or gum arabic; should be replaced with safer perchlorates wherever possible):
- Potassium chlorate
Potassium chlorate is a compound containing potassium, chlorine and oxygen atoms, with the molecular formula KClO3. In its pure form, it is a white crystalline substance. It is the most common chlorate in industrial use...
– much less stable than perchlorate, hazardous, avoid if possible. High burning speed, easy ignition. Slightly more hygroscopic than potassium nitrate. Produces smoke of potassium chloride. Can act as a chlorine donor. High impact and friction sensitivity with sulfur and sulfides. With ammonium salts produces unstable ammonium chlorate. Used in match head compositions, some colored smokeColored smoke is a kind of smoke created by an aerosol of small particles of a suitable pigment or dye.Colored smoke can be used for smoke signals, often in a military context. It can be produced by smoke grenades, or by various other pyrotechnical devices...
s, and small firecrackers and toy caps.
- Barium chlorate
Barium chlorate is a white crystalline solid. It is an irritant, as are all barium compounds. If consumed, barium chlorate can cause nausea, vomiting, and diarrhea. It is used in pyrotechnics to produce a green color...
– also serves as a green colorant in fireworks; sensitive, better to avoid. Almost non-hygroscopic. Compositions may spontaneously combust in sunlight. Very good green colorant, even in lower-temperature flames.
- Sodium chlorate
Sodium chlorate is a chemical compound with the chemical formula . When pure, it is a white crystalline powder that is readily soluble in water. It is hygroscopic. It decomposes above 250 °C to release oxygen and leave sodium chloride...
– much less stable than perchlorate, hazardous, also serves as yellow colorant, hygroscopic
- Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
s (when mixing with aluminium, boric acid should be added as a stabilizer):
- Potassium nitrate
Potassium nitrate is a chemical compound with the formula KNO3. It is an ionic salt of potassium ions K+ and nitrate ions NO3−.It occurs as a mineral niter and is a natural solid source of nitrogen. Its common names include saltpetre , from medieval Latin sal petræ: "stone salt" or possibly "Salt...
– very common, used in black powder and wide variety of compositions. Not very hygroscopic. At lower temperatures (with ordinary fuels like rosin or shellac) not very efficient, does not burn well, produces potassium nitrite. At higher temperatures, with charcoal and sulfur or with magnesium, decomposes well. Does not produce sufficient temperature to make colored flames, except when magnesium is added. Makes good sparks. Presence in dust makes the dust hazardous and very flammable.
- Sodium nitrate
Sodium nitrate is the chemical compound with the formula NaNO3. This salt, also known as Chile saltpeter or Peru saltpeter to distinguish it from ordinary saltpeter, potassium nitrate, is a white solid which is very soluble in water...
– also a yellow colorant, hygroscopic. Gives intense yellow light, used for illumination compositions. Presence in dust makes the dust hazardous. At lower temperatures produces nitrite ash, at higher temperatures decomposes completely.
- Calcium nitrate
Calcium nitrate, also called Norgessalpeter , is the inorganic compound with the formula Ca2. This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate. It is mainly used as a component in fertilizers but is found other applications...
– also a red-orange colorant, enhances other colors
- Ammonium nitrate – used in some less common composite rocket propellants, hygroscopic, decomposes at too low temperature; when dry reacts with Al, Zn, Pb, Sb, Bi, Ni, Cu, Ag, Cd; when wet reacts also with Fe. Forms an explosive compound with copper.
- Barium nitrate
Barium nitrate with chemical formula Ba2 is a salt of barium and the nitrate ion.Barium nitrate exists as a white solid at room temperature. It is soluble in water, and like other soluble barium compounds, is toxic and should be handled with care...
– most common oxidizer/colorant for green and white colors, but with somewhat weak colorant effect;requires a chlorine donor. Also used in flash powders and some military infrared flares. Barium also serves as a stabilizer for the mixtures; decomposes at higher temperatures than nitrates of lighter metals and promotes higher burning temperatures. With aluminium produces bright silver sparks; when used with aluminium, addition of boric acid as stabilizer is advised. Not very hygroscopic.
- Strontium nitrate
Strontium nitrate is an inorganic compound with the formula Sr2. This colourless solid is used as an colorant in pyrotechnics.- Preparation:Strontium nitrate is typically generated by the reaction of nitric acid on strontium carbonate.....
– most common oxidizer/colorant for red colors in flares, fires, and stars; strontium also serves as a stabilizer for the mixtures. At lower temperatures (with organic fuels) produces strontium nitrite ash which can smother the flame; decomposes completely at higher temperatures (with magnesium). Colorant for low-temperature flames, colorant and oxidizer for hot flames.
- Caesium nitrate
Caesium nitrate is a chemical compound with the chemical formula CsNO3. It is used in pyrotechnic compositions, as a colorant and an oxidizer, e.g. in decoys and illumination flares...
– used in some military infrared flare compositions
- Permanganate
A permanganate is the general name for a chemical compound containing the manganate ion, . Because manganese is in the +7 oxidation state, the permanganate ion is a strong oxidizing agent. The ion has tetrahedral geometry...
s:
- Potassium permanganate
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. It is a salt consisting of K+ and MnO4− ions. Formerly known as permanganate of potash or Condy's crystals, it is a strong oxidizing agent. It dissolves in water to give intensely purple solutions, the...
– used in early mixtures, now considered to be sensitive and unstable
- Ammonium permanganate
Ammonium permanganate is the chemical compound NH4MnO4, or NH3·HMnO4. It is soluble in water. It is a strong oxidizer, owing to its permanganate anion, and it is a moderately strong explosive, owing to the combination of oxidizer permanganate anion and reducing ammonium cation...
– a moderately powerful explosive
- Chromate
Chromate salts contain the chromate anion, CrO42−. Dichromate salts contain the dichromate anion, Cr2O72−. They are oxyanions of chromium in the oxidation state +6. They are moderately strong oxidizing agents.- Chemical properties :...
s:
- Barium chromate
Barium chromate is a fine light yellow powder with the formula BaCrO4. The chromium occurs in the +6 oxidation state. It is an oxidizing agent, and produces a green flame when heated, the result of barium ions.-Reactions:...
– used in delay compositions, e.g. in fireworks rockets
- Lead chromate – used in delay compositions
- Potassium dichromate – used infrequently as an oxidizer; can be used as a surface treatment for passivation of magnesium particles, also as a catalyst and in some matches; potassium perchlorate often added
- Oxide
An oxide is a chemical compound that contains at least one oxygen atom in its chemical formula. Metal oxides typically contain an anion of oxygen in the oxidation state of −2....
s and peroxideA peroxide is a compound containing an oxygen–oxygen single bond or the peroxide anion .The O−O group is called the peroxide group or peroxo group. In contrast to oxide ions, the oxygen atoms in the peroxide ion have an oxidation state of −1.The simplest stable peroxide is hydrogen peroxide...
s:
- Barium peroxide
Barium peroxide is the chemical compound with the formula BaO2. This grey-white solid is one of the most common inorganic peroxides. Barium peroxide is an oxidizing agent, which is used for bleaching...
– unstable, spontaneously decomposes, compositions containing it should not be stored
- Strontium peroxide
Strontium peroxide is a whitish inorganic compound, a peroxide of strontium. It is an oxidizing agent used for bleaching. It is used in some pyrotechnic compositions as an oxidizer and a vivid red pyrotechnic colorant. Its CAS number is ....
- Lead tetroxide
Lead tetroxide, also called minium, red lead or triplumbic tetroxide, is a bright red or orange crystalline or amorphous pigment. Chemically, red lead is lead tetroxide, Pb3O4, or 2PbO·PbO2....
– versatile but toxic
- Lead dioxide – used in friction-sensitive compositions, eg. match
A match is a tool for starting a fire under controlled conditions. A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface...
es
- Bismuth trioxide
Bismuth oxide is perhaps the most industrially important compound of bismuth. It is also a common starting point for bismuth chemistry. It is found naturally as the mineral bismite and sphaerobismoite , but it is usually obtained as a by-product of the smelting of copper and lead ores...
– used as a safe alternative to lead tetroxide in some compositions
- Iron(III) oxide
Iron oxide or ferric oxide is the inorganic compound with the formula Fe2O3. It is one of the three main oxides of iron, the other two being iron oxide , which is rare, and iron oxide , which also occurs naturally as the mineral magnetite. As the mineral known as hematite, Fe2O3 is the main...
– a high temperature oxidizer, a catalyst
- Iron(II,III) oxide
Iron oxide is the chemical compound with formula Fe3O4. It is one of a number of iron oxides, the others being iron oxide , which is rare, and iron oxide also known as hematite. It occurs in nature as the mineral magnetite. It contains both Fe2+ and Fe3+ ions and is sometimes formulated as FeO ∙...
– an oxidizer in ThermiteThermite is a pyrotechnic composition of a metal powder and a metal oxide that produces an exothermic oxidation-reduction reaction known as a thermite reaction. If aluminium is the reducing agent it is called an aluminothermic reaction...
and ThermateThermate is a variation of thermite and is an incendiary pyrotechnic composition that can generate short bursts of very high temperatures focused on a small area for a short period of time. It is used primarily in incendiary grenades....
- Manganese(IV) oxide
Manganese oxide is the inorganic compound with the formula . This blackish or brown solid occurs naturally as the mineral pyrolusite, which is the main ore of manganese and a component of manganese nodules. The principal use for MnO2 is for dry-cell batteries, such as the alkaline battery and the...
– an oxidizer in manganese thermite, a catalyst
- Chromium(III) oxide
Chromium oxide is the inorganic compound of the formula Cr2O3. It is one of principal oxides of chromium and is used as a pigment. In nature, it occurs as the rare mineral eskolaite.-Structure and properties:...
– an oxidizer in chromium thermite
- Tin(IV) oxide – an oxidizer in some delay charges
- Sulfate
In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...
s (reactions require high temperatures and strongly reducing fuels):
- Barium sulfate
Barium sulfate is the inorganic compound with the chemical formula BaSO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs as the mineral barite, which is the main commercial source of barium and materials prepared from it...
– a high-temperature oxidizer for e.g. strobe compositions, a green colorant
- Calcium sulfate
Calcium sulfate is a common laboratory and industrial chemical. In the form of γ-anhydrite , it is used as a desiccant. It is also used as a coagulant in products like tofu. In the natural state, unrefined calcium sulfate is a translucent, crystalline white rock...
– a high-temperature oxidizer for e.g. strobe compositions, a red-orange colorant; calcium salts used to deepen fireworks colors
- Potassium sulfate
Potassium sulfate is a non-flammable white crystalline salt which is soluble in water...
– a high-temperature oxidizer, a purple colorant
- Sodium sulfate
Sodium sulfate is the sodium salt of sulfuric acid. When anhydrous, it is a white crystalline solid of formula Na2SO4 known as the mineral thenardite; the decahydrate Na2SO4·10H2O has been known as Glauber's salt or, historically, sal mirabilis since the 17th century. Another solid is the...
– a high-temperature oxidizer, a yellow colorant
- Strontium sulfate
Strontium sulfate is the sulfate salt of strontium. It is a white crystalline powder and occurs in nature as the mineral celestine. It is poorly soluble in water to the extent of 1 part in 8,800. It is more soluble in dilute HCl and nitric acid and appreciably soluble in alkali chloride solutions...
– a high-temperature oxidizer, a red colorant
- Organic chemicals
- Guanidine nitrate
Guanidine nitrate is a high energy fuel used in some gas generator and solid rocket propellant applications.-Overview:Guanidine nitrate is the salt formed from guanidine and nitric acid. It has the chemical formula C3NO3. It has been used as a monopropellant in the Jetex engine for model airplanes....
– used in some high power rocket fuels, propellants, and blue firework compositions
- Hexanitroethane
Hexanitroethane is an organic compound with chemical formula C2N6O12 or 3C-C3. It is a solid matter with a melting point of 135 °C....
– used in some special military compositions
- Cyclotrimethylene trinitramine – used in some double-base propellants
- Cyclotetramethylene Tetranitramine – used in some double-base propellants
- Others
- Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
– oxidizer for zinc in zinc-sulfur fuels
- Teflon – oxidizer for some metal fuels
- Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...
– oxidizer for titanium, forming titanium diboride
Corresponding sodium salts can be substituted for potassium ones.
Additives
- Coolants. For some purposes it is necessary to lower the burning temperature of the mixture, and/or slow down the reaction rate. For such purpose, inert materials (eg. clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
, diatomaceous earthDiatomaceous earth also known as diatomite or kieselgur/kieselguhr, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a particle size ranging from less than 1 micrometre to more than 1 millimetre, but typically 10 to...
, alumina, silica, magnesium oxideMagnesium oxide , or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium . It has an empirical formula of and consists of a lattice of Mg2+ ions and O2– ions held together by ionic bonds...
, or others) or endothermically decomposing materials (eg. carbonateIn chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
s) are added. OxamideOxamide is the organic compound with the formula 2. This white crystalline solid is soluble in ethanol, slightly soluble in water and insoluble in diethyl ether...
is used as a high performance burning rate suppressant in some propellant compositions. Strontium carbonateStrontium carbonate is the carbonate salt of strontium that has the appearance of a white or grey powder. It occurs in nature as the mineral strontianite.- Chemical properties :...
is used as a fire retardant in some gunpowders.
- Flame suppressants. Potassium nitrate
Potassium nitrate is a chemical compound with the formula KNO3. It is an ionic salt of potassium ions K+ and nitrate ions NO3−.It occurs as a mineral niter and is a natural solid source of nitrogen. Its common names include saltpetre , from medieval Latin sal petræ: "stone salt" or possibly "Salt...
and potassium sulfatePotassium sulfate is a non-flammable white crystalline salt which is soluble in water...
are commonly used.
- Opacifier
An opacifier is a substance added to a material in order to make the ensuing system opaque. An example of a chemical opacifier is tin dioxide , which is used to opacify ceramic glazes and milk glass; bone ash is also used....
s. Some solid rocket propellants have problems with radiative heat transfer through the material, which may lead to explosion. Carbon blackCarbon black is a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, ethylene cracking tar, and a small amount from vegetable oil. Carbon black is a form of amorphous carbon that has a high surface-area-to-volume ratio, although its...
and graphiteThe mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...
are often used to inhibit this effect.
- Colorants
A pyrotechnic colorant is a chemical compound which causes a flame to burn with a particular color. These are used to create the colors in pyrotechnic compositions like fireworks and colored fires. The color-producing species are usually created from other chemicals during the reaction. Metal salts...
, sometimes in combination with sources of chlorineChlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...
. Usually salts of suitable metals, often bariumBarium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...
, strontiumStrontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and...
, calciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
, sodiumSodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
, copperCopper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
, etc. The salt may simultaneously serve as an oxidizer. CopperCopper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
metal can be also used. Copper acetoarsenite with potassium perchlorate provides richest blue.
- Chlorine donors. Used together with colorants. Presence of chlorides increases the volatility of the color-imparting metals and enhances the color intensity. Polyvinyl chloride
Polyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...
, polyvinylidene chloridePolyvinylidene chloride is a polymer derived from vinylidene chloride.-History:Ralph Wiley, a Dow Chemical lab worker, accidentally discovered polyvinylidene chloride in 1933. While cleaning laboratory glassware, he came across a vial he could not scrub clean...
, SaranSaran is the trade name for a number of polymers made from vinylidene chloride , along with other monomers. The main advantage of Saran film is its very low permeability to water vapor, flavor and aroma molecules, and oxygen compared with other plastics...
, chlorinated paraffins, chlorinated rubberNatural rubber, also called India rubber or caoutchouc, is an elastomer that was originally derived from latex, a milky colloid produced by some plants. The plants would be ‘tapped’, that is, an incision made into the bark of the tree and the sticky, milk colored latex sap collected and refined...
(e.g. Parlon), hexachloroethaneHexachloroethane, also known as perchloroethanes , C2Cl6, is a colorless solid at room temperature which is used by the US Military in smoke compositions, e.g...
, hexachlorobenzeneHexachlorobenzene, or perchlorobenzene, is a chlorocarbon with the molecular formula C6Cl6. It is a fungicide formerly used as a seed treatment, especially on wheat to control the fungal disease bunt...
(most common chlorine donor until 1970's, now rarely used), and some other organochlorideAn organochloride, organochlorine, chlorocarbon, chlorinated hydrocarbon, or chlorinated solvent is an organic compound containing at least one covalently bonded chlorine atom. Their wide structural variety and divergent chemical properties lead to a broad range of applications...
s and inorganic chlorideThe chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...
s (e.g. ammonium chlorideAmmonium chloride NH4Cl is an inorganic compound with the formula NH4Cl. It is a white crystalline salt that is highly soluble in water. Solutions of ammonium chloride are mildly acidic. Sal ammoniac is a name of natural, mineralogical form of ammonium chloride...
, mercurous chloride) are used as chlorine donors. Perchlorates and chlorates play this role together with their main use as oxidizers. Chlorine donors are often used also in smoke compositionA smoke composition is a pyrotechnic composition designed primarily to generate smoke. Smoke compositions are used as obscurants or for generation of signaling smokes. Some are used as a payload of smoke bombs and smoke grenades.-Obscurants:...
s, e.g. hexachloroethaneHexachloroethane, also known as perchloroethanes , C2Cl6, is a colorless solid at room temperature which is used by the US Military in smoke compositions, e.g...
together with zinc oxideZinc oxide is an inorganic compound with the formula ZnO. It is a white powder that is insoluble in water. The powder is widely used as an additive into numerous materials and products including plastics, ceramics, glass, cement, rubber , lubricants, paints, ointments, adhesives, sealants,...
to produce smokeSmoke is a collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires , but may also be used for pest...
based on zinc chlorideZinc chloride is the name of chemical compound with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. ZnCl2 itself is hygroscopic and even deliquescent. Samples should therefore be protected from...
.
- Catalysts. Propellant formulas often require a catalyst to burn faster and more stably. Transition metal
The term transition metal has two possible meanings:*The IUPAC definition states that a transition metal is "an element whose atom has an incomplete d sub-shell, or which can give rise to cations with an incomplete d sub-shell." Group 12 elements are not transition metals in this definition.*Some...
ions and complexes tend to be used. Certain oxidizers often serve as catalysts. E.g. ammonium dichromateAmmonium dichromate is the inorganic compound with the formula 2Cr2O7. In this compound, as in all chromates and dichromates, chromium is in a +6 oxidation state, commonly known as hexavalent chromium...
is used as a catalyst in ammonium nitrate based propellant formulas. Other catalysts are e.g. iron(III) oxideIron oxide or ferric oxide is the inorganic compound with the formula Fe2O3. It is one of the three main oxides of iron, the other two being iron oxide , which is rare, and iron oxide , which also occurs naturally as the mineral magnetite. As the mineral known as hematite, Fe2O3 is the main...
, hydrated ferric oxide, manganese dioxide, potassium dichromate, copper chromite, lead salicylate, lead stearate, lead 2-ethylhexoate, copper salicylateCopper salicylate is a compound with formula Cu22. It is the copper salt of salicylic acid....
, copper stearate, lithium fluorideLithium fluoride is an inorganic compound with the formula LiF. It is the lithium salt of hydrofluoric acid. This white solid is a simple ionic compound. Its structure is analogous to that of sodium chloride, but it is much less soluble in water. It is mainly used as a component of molten...
, n-butyl ferrocene, di-n-butyl ferrocene.
- Stabilizers
In chemistry a stabilizer is a chemical which tends to inhibit the reaction between two or more other chemicals. It can be thought of as the antonym to a catalyst...
. Some mixtures, eg. containing chlorates, tend to degrade and create acidic byproducts. CarbonateIn chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
s (eg. sodiumSodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...
, calciumCalcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
, or barium carbonateBarium carbonate , also known as witherite, is a chemical compound used in rat poison, bricks, ceramic glazes and cement.Witherite crystallizes in the orthorhombic system...
) or other mildly alkaline materials can be added to scavenge such acids. Boric acidBoric acid, also called hydrogen borate or boracic acid or orthoboric acid or acidum boricum, is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a...
can be used to inhibit the sensitivity of aluminium to moisture, and to stabilize mixtures of metals with nitrates (which can otherwise form amides which react exothermically with metals and can cause spontaneous initiation). Many organic nitrated amines are used as stabilizers as well, e.g. 2-nitrodiphenylamine2-Nitrodiphenylamine, also called NDPA, 2-NDPA, 2NO2DPA, Sudan Yellow 1339, C.I. 10335, CI 10335, phenyl 2-nitrophenylamine, 2-nitro-N-phenylaniline, or N-phenyl-o-nitroaniline, is an organic chemical, a nitrated aromatic amine, a derivate of diphenylamine. Its chemical formula is C12H10N2O2, or...
. Petroleum jellyPetroleum jelly, petrolatum, white petrolatum or soft paraffin, CAS number 8009-03-8, is a semi-solid mixture of hydrocarbons , originally promoted as a topical ointment for its healing properties...
, castor oilCastor oil is a vegetable oil obtained from the castor bean . Castor oil is a colorless to very pale yellow liquid with mild or no odor or taste. Its boiling point is and its density is 961 kg/m3...
, linseed oilLinseed oil, also known as flaxseed oil, is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant . The oil is obtained by cold pressing, sometimes followed by solvent extraction...
, etc. can be used as stabilizers, also to add hydrophobicity to particles and protect metals (especially iron and magnesium) from corrosion. Ethyl centralite and 2-nitrodiphenylamine2-Nitrodiphenylamine, also called NDPA, 2-NDPA, 2NO2DPA, Sudan Yellow 1339, C.I. 10335, CI 10335, phenyl 2-nitrophenylamine, 2-nitro-N-phenylaniline, or N-phenyl-o-nitroaniline, is an organic chemical, a nitrated aromatic amine, a derivate of diphenylamine. Its chemical formula is C12H10N2O2, or...
are used in some rocket propellants.
- Anticaking agent
An anticaking agent is an additive placed in powdered or granulated materials, such as table salt, to prevent the formation of lumps, easing packaging, transport, and consumption....
s. Eg. fumed silicaFumed silica, also known as pyrogenic silica because it is produced in a flame, consists of microscopic droplets of amorphous silica fused into branched, chainlike, three-dimensional secondary particles which then agglomerate into tertiary particles. The resulting powder has an extremely low bulk...
. For powder compositions, e.g. flash powderFlash powder is a pyrotechnic composition, a mixture of oxidizer and metallic fuel, which burns quickly and if confined produces a loud report. It is widely used in theatrical pyrotechnics and fireworks and was once used for flashes in photography.Different varieties of flash powder are made from...
or gunpowderGunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...
. GraphiteThe mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...
is used in some cases to coat the grains, lubricate them, and dissipate static electricityStatic electricity refers to the build-up of electric charge on the surface of objects. The static charges remain on an object until they either bleed off to ground or are quickly neutralized by a discharge. Static electricity can be contrasted with current electricity, which can be delivered...
. Magnesium carbonateMagnesium carbonate, MgCO3, is a white solid that occurs in nature as a mineral. Several hydrated and basic forms of magnesium carbonate also exist as minerals...
used too, together with its function as carbonate stabilizer.
- Binders
-See also:*Adhesive or Glue*Cement*Paint...
. Often gum-Natural gums:* Natural gum, any of a number of naturally occurring resinous materials in vegetative species* Gum anima* Gum arabic, used as food additive, adhesive et al.* Cassia gum* Dammar gum* Gellan gum* Guar gum* Kauri gum* Locust bean gum* Spruce gum...
s and resinResin in the most specific use of the term is a hydrocarbon secretion of many plants, particularly coniferous trees. Resins are valued for their chemical properties and associated uses, such as the production of varnishes, adhesives, and food glazing agents; as an important source of raw materials...
s, e.g. gum arabic220px|thumb|right|Acacia gumGum arabic, also known as acacia gum, chaar gund, char goond, or meska, is a natural gum made of hardened sap taken from two species of the acacia tree; Acacia senegal and Acacia seyal...
, red gum, guar gumGuar gum, also called guaran, is a galactomannan. It is primarily the ground endosperm of guar beans. The guar seeds are dehusked, milled and screened to obtain the guar gum. It is typically produced as a free-flowing, pale, off-white-colored, coarse to fine ground powder.-Production:Guar gum is an...
, copalCopal is a name given to tree resin that is particularly identified with the aromatic resins used by the cultures of pre-Columbian Mesoamerica as ceremonially burned incense and other purposes...
, carboxymethyl celluloseCarboxymethyl cellulose or cellulose gum is a cellulose derivative with carboxymethyl groups bound to some of the hydroxyl groups of the glucopyranose monomers that make up the cellulose backbone...
, nitrocelluloseNitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton...
, rice starchStarch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...
, cornstarchCorn starch, cornstarch, cornflour or maize starch is the starch of the corn grain obtained from the endosperm of the corn kernel.-History:...
, shellacShellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes , which are dissolved in ethyl alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish...
, dextrinDextrins are a group of low-molecular-weight carbohydrates produced by the hydrolysis of starch or glycogen. Dextrins are mixtures of polymers of D-glucose units linked by α- or α- glycosidic bonds....
. Binders can also serve as fuels. CamphorCamphor is a waxy, white or transparent solid with a strong, aromatic odor. It is a terpenoid with the chemical formula C10H16O. It is found in wood of the camphor laurel , a large evergreen tree found in Asia and also of Dryobalanops aromatica, a giant of the Bornean forests...
can be used as a plasticizerPlasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added; these include plastics, cement, concrete, wallboard, and clay. Although the same compounds are often used for both plastics and concretes the desired effects and results are...
. Binders are used in manufacture of compact compositions, e.g. pyrotechnic starPyrotechnic stars are pellets or simply pieces of pyrotechnic composition which may contain metal powders, salts or other compounds that, when ignited, burn a certain colour or exude a spark effect. They are a part of all projectile-type fireworks. The most common is the aerial shell. When...
s. Polymers like HTPB and PBANPolybutadiene acrylonitrile copolymer, also noted as polybutadiene — acrylic acid — acrylonitrile terpolymer.This was the binder formulation widely used on the 1960-70's big boosters...
are often used for rocket fuels. Other polymers used are e.g. polyethylenePolyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...
or polyvinyl chloridePolyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...
can be encountered as well.
- Plasticizer
Plasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added; these include plastics, cement, concrete, wallboard, and clay. Although the same compounds are often used for both plastics and concretes the desired effects and results are...
s. Improve the mechanical properties of the propellant particles. For composite rocket propellants, dioctyl adipateDioctyl adipate or DOA is a plasticizer. DOA is a diester of adipic acid and two equivalents of n-octanol. Its chemical formula is 22424.DEHA is sometimes incorrectly called dioctyl adipate....
, isodecyl pelargonate, and dioctyl phthalate are often used. Plasticizers can also be other energetic materials (common in smokeless powders), e.g. nitroglycerine, butanetriol trinitrate, dinitrotoluene2,4-Dinitrotoluene or Dinitro is an organic compound with the formula C6H32. This pale yellow crystalline solid is well known as a precursor to trinitrotoluene but is mainly used in the polymer industry....
, trimethylolethane trinitrateTrimethylolethane trinitrate , also known as metriol trinitrate or nitropentaglycerin, is a nitro ester. It is a high explosive similar to nitroglycerin. It is a transparent oily liquid, colorless to light brown. It is odorless. It is used in some solid propellants and smokeless powders as a...
, diethylene glycol dinitrateDiethylene glycol dinitrate is a nitrated alcohol ester produced by the action of concentrated nitric acid, normally admixed with an excess of strong sulfuric acid as a dehydrating agent, upon diethylene glycol....
, triethylene glycol dinitrateTriethylene glycol dinitrate is a nitrated alcohol ester of triethylene glycol. It is used as an energetic plasticizer in explosives and propellants. Its chemical formula is O2N-O-CH2CH2-O-CH2CH2-O-CH2CH2-O-NO2. It is a pale yellow oily liquid...
, bis(2,2-dinitropropyl)formal, bis(2,2-dinitropropyl)acetal, 2,2,2-trinitroethyl 2-nitroxyethyl ether, and others.
- Curing and crosslinking agents. Used to harden the polymer component of composite rocket propellants. They include paraquinone dioxime, toluene-2,4-diisocyanate, tris(1-(2-methyl) aziridinyl) phosphine oxide, N,N,O-tri(1,2-epoxy propyl)-4-aminophenol, and isophorone diisocyanate
Isophorone diisocyanate is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is produced in relatively small quantities, accounting for only 3.4% of the global diisocyanate market in the year 2000...
.
- Bonding agents. Used to increase the level of bonding between the binder and the fuel/oxidizer particles. They include tris(1-(2-methyl) azirinidyl) phosphine oxide and triethanolamine
Triethanolamine, often abbreviated as TEA, is an organic chemical compound which is both a tertiary amine and a triol. A triol is a molecule with three alcohol groups. Like other amines, triethanolamine is a strong base due to the lone pair of electrons on the nitrogen atom. Triethanolamine can...
.
External links