Ammonium Polyphosphate (APP) is a non-halogen flame retardant which acts by an intumescence mechanism.
When APP is exposed to fire or heat, it decomposes to polymeric phosphate acid and ammonia.
The polyphosphoric acid reacts with hydroxyl groups to form a nonstable phosphate ester.
Following dehydration of the phosphate ester, a carbon foam is built up on the surface and acts as an insulation layer.
APP is used in plastics such as PP, PVC, PE, polyester, rubber, and expandable fireproof coatings.
Ammonium polyphosphate is an inorganic salt of polyphosphoric acid and ammonia.
The chain length (n) of this polymeric compound is both variable and branched, and can be greater than 1 000.
Short and linear chain APPs (n < 100) are more water sensitive (hydrolysis) and less thermally stable than longer chain APPs (n >1000), which show a very low water solubility (< 0.1 g/ 100 ml).
APP is a stable, non-volatile compound.
In contact with water APP it slowly gets hydrolysed to monoammonium phosphate (orthophosphate).
Higher temperatures and prolonged exposure to water will accelerate the hydrolysis.
Long chain APP starts to decompose at temperatures above 300 °C to polyphosphoric acid and ammonia.
Short chain APP will begin to decompose at temperatures above 150 °C.
There are two main families of ammonium polyphosphate : Crystal phase I APP (APP I) and Crystal phase II APP (APP II).
Crystal phase I APP (APP I) is characterized by a variable linear chain length, showing a lower decomposition temperature (aprox 150°C) and a higher water solubility than Crystal Phase II Ammonium Polyphosphate.
The general structure of APP is given below.
In APP I, n (number of phosphate units) is generally lower than 100.
Ammonium Polyphosphate Synonyms
Ammonium Poly-phosphate, Ammonium Poly phosphate, Polyphosphoric acids ammonium salts, Triammonium orthophosphate, Ammonium phosphate tribasic, Exolit AP 422, FR CROS 484, APP, APP-130, Phase I Grade APP130, H48N11O25P7, UNII-2ZJF06M0I9
Ammonium polyphosphate (APP) is used as a flame retardant in many applications such as paints and coatings, and in a variety of polymers: the most important ones are polyolefins, and particularly polypropylene.
Further applications are thermosets, where APP is used in unsaturated polyesters and gel coats, epoxies and polyurethane castings.
APP is also applied to flame retard polyurethane foams.
Flame Retardant
Intumescent
Flame Retardant
Limiting Oxygen
Polyurethanes
Time to Ignition
Flame Retardancy
Fire Retardant
Ammonium polyphosphate is used as a flame retardant in many applications such as paints and coatings, and in a variety of polymers: the most important ones are polyolefins, and particularly polypropylene, where APP is part of intumescent systems.
KEY WORDS:
Exolit AP 422, FR CROS 484, CS FR APP 23, Ammonium triphosphate, Pentaammonium triphosphate, 14693-67-5, Novawhite, Sumisafe, Antiblaze MC, Antiblaze MCM
Inorganic phosphorus
Ammonium polyphosphate (APP) and melamine polyphosphate (MPP) are two typical inorganic phosphorus flame retardants.
APP is a branched or linear polymeric compound with a variable degree of polymerization (n).
Generally, APP of a low degree of polymerization (n ≤ 100, crystalline form I) is water soluble or water sensitive, while APP with longer chains (n ≥ 1000, crystalline form II) displays a very low water solubility (<0.1 g/100 mL).
Compared with APP, MPP holds higher thermal stability and lower water sensitivity.
In general, long-chain APP starts to degrade at a temperature of above 300°C, generating ammonia and polyphosphoric acid, while the short-chain one begins decomposing at 150°C.
Thus choosing APP as the flame retardant strongly depends on the processing temperature of materials.
When APP is added into a polymeric material containing oxygen and/or nitrogen elements, the char may form.
At high temperature, APP degrades to create free acidic hydroxyl groups and form ultraphosphate and polyphosphoric acid, which can catalyze the dehydration reaction of polymers to yield char residues. However, in nonself-charring polymeric materials, APP only alters the degradation mechanism of the polymer.
Inorganic Filler Materials with Flame Retardant Properties
Ammonium polyphosphate (APP) and melamine pyrophosphate (MPP) are considered to be the most effective phosphorus-based flame retardants applicable for unsaturated polyesters.
The degradation mechanism of APP has been studied extensively by thermal methods and consists of elimination of water and ammonia and formation of polyphosphoric acid, which is subsequently evaporated and dehydrated at temperatures above 250°C.
With melamine-based flame retardants, two mechanisms of action are encountered.
Sublimation of melamine at ca. 350°C and subsequent decomposition processes yielding cyanamide are very endothermic processes that absorb energy from the burning matter.
Upon heating, melamine also progressively condensates under evolution of ammonia to thermally stable condensation products: melam, melem, and melon.
This reaction competes with melamine volatilization and is more pronounced if melamine is entrapped within the charring material.
The combination with phosphate chemistry further improves the efficiency of this flame retardant.
Flame Retardants / Smoke Suppressants > Ammonium Polyphosphates (APP)
Ammonium Polyphosphate (APP) is a stable and non-volatile compound.
It comes under the category of halogen free flame retardants and works as a smoke suppressant too.
Ammonium Polyphosphate (APP) is very cost effective when compared to other halogen free systems.
Lower loading into polymers ensures good retention of mechanical and electrical properties and excellent flow.
Allowing plastics to exhibit excellent processability, Ammonium Polyphosphate (APP) is used as an efficient flame retardant in the furniture industry and for interior fabrics for the automotive industry.
CAS Number: 68333-79-9
Other names: Exolit AP 422, FR CROS 484, CS FR APP 231
Ammonium polyphosphate commercially produced by Clariant, (former business area of Hoechst AG), Budenheim and other sources is an inorganic salt of polyphosphoric acid and ammonia containing both chains and possibly branching.
Its chemical formula is [NH4 PO3]n(OH)2 showing that each monomer consists of an orthophosphate radical of a phosphorus atom with three oxygens and one negative charge neutralized by an ammonium cation leaving two bonds free to polymerize.
In the branched cases some monomers are missing the ammonium anion and instead link to three other monomers.
The properties of ammonium polyphosphate depend on the number of monomers in each molecule and to a degree on how often it branches.
Shorter chains (n<100) are more water sensitive and less thermally stable than longer chains (n>1000),[1] but short polymer chains (e.g. pyro-, tripoly-, and tetrapoly-) are more soluble and show increasing solubility with increasing chain length.
Ammonium polyphosphate can be prepared by reacting concentrated phosphoric acid with ammonia.
However, iron and aluminum impurities, soluble in concentrated phosphoric acid, form gelatinous precipitates or "sludges" in ammonium polyphosphate at pH between 5 and 7.
Other metal impurities such as copper, chromium, magnesium, and zinc form granular precipitates.
However, depending on the degree of polymerization, ammonium polyphosphate can act as a chelating agent to keep certain metal ions dissolved in solution.
Ammonium polyphosphate is used as a food additive, emulsifier, (E number: E545) and as a fertilizer.
Ammonium polyphosphate (APP) is also used as a flame retardant in many applications such as paints and coatings, and in a variety of polymers: the most important ones are polyolefins, and particularly polypropylene, where APP is part of intumescent systems.
Compounding with APP-based flame retardants in polypropylene is described in.
Further applications are thermosets, where APP is used in unsaturated polyesters and gel coats (APP blends with synergists), epoxies and polyurethane castings (intumescent systems).
APP is also applied to flame retard polyurethane foams.
Ammonium polyphosphates as used as flame retardants in polymers have long chains and a specific crystallinity (Form II).
They start to decompose at 240 °C to form ammonia and phosphoric acid.
The phosphoric acid acts as an acid catalyst in the dehydration of carbon-based poly-alcohols, such as cellulose in wood.
The phosphoric acid reacts with alcohol groups to form heat-unstable phosphate esters.
The esters decompose to release carbon dioxide and regenerate the phosphoric acid catalyst.
In the gas phase, the release of non-flammable carbon dioxide helps to dilute the oxygen of the air and flammable decomposition products of the material that is burning.
In the condensed phase, the resultant carbonaceous char helps to shield the underlying polymer from attack by oxygen and radiant heat.
Use as an intumescent is achieved when combined with starch-based materials such as pentaerythritol and melamine as expanding agents.
The mechanisms of intumescence and the mode of action of APP are described in a series of publications
Ammonium Polyphosphate
Ammonium polyphosphate (APP) is composed of polyphosphoric acid and ammonia in the chains.
It is reported to act mainly in the condensed phase to promote char formation with acid catalysis; but also in some cases dilute the flammable decomposition products with the release of non-flammable carbon dioxide in the gas phase.
Ammonium Polyphosphate
Ammonium poly-phosphate is a halogen-free flame retardant for unsaturated polyester resin composites.
Commonly used are ammonium polyphosphates having the general formula .
A significant reduction of the flame spread index is achieved by a combination of a polyhydroxy compound, a polyphosphate, melamine, cyanuric acid, melamine salts, e.g., melamine cyanurate, and a polyacrylate monomer.
The effect of aluminum trihydroxide in combination with ammonium polyphosphate has been investigated.
Thermogravimetric experiments revealed an improved thermal stability in the range of 200–600 °C.
Obviously, aluminum trihydroxide is more efficient than calcium carbonate in delaying the time of ignition and lowering the yield of carbon monoxide.
However, no significant synergistic effect in reducing the peak heat release was observed.
The fire retardant polyacrylate component should be distinguished from the unsaturated monomers that may be included as crosslinkers in the resin systems.
It cannot be ruled out that the polyacrylate may become involved in the crosslinking reactions of such systems.
However, it has been observed that the fire retardant effect of the polyacrylates is also effective in those resin systems that do not involve curing by way of unsaturated groups.
Preferred polyacrylates are those having backbones of a type that is known to contribute to char formation, for example those having alkylene or oxyalkylene backbones
Phosphorus-containing flame retardants
This category generally includes phosphate esters, ammonium orthophosphates, ammonium polyphosphates, and red phosphorus.
These retardants are oxidized during combustion to phosphorus oxide, which turns into a phosphoric acid on its interaction with water.
This acid stimulates the take-up of water out of the bottom layer of the material that has decomposed thermally, leading to char, thus increasing the carbonate waste as well as reducing the emission of combustible gases.
The phosphorous compounds work in the solid state, but can also operate in a gaseous state when they contain halogenated compounds.
This group represents 20% of the world flame retardant production.
Poly(methyl methacrylate) with Ammonium Polyphosphate
Several detailed studies have been made in which the fire retardant additive is ammonium polyphosphate (APP).
It is necessary first to understand the effect of heat on APP as the temperature is gradually increased.
In the temperature region 100–260 °C, less than 5% weight loss (as ammonia and water) occurs. Some free acid groups are formed, which condense to form crosslinks.
The physical state changes from powder to a glassy, hygroscopic solid, from which gas evolution is less easy.
The Psingle bondOsingle bondP links produced are easily hydrolyzed to acidic groups.
Between 260 and 350 °C the rate of evolution of NH3 and H2O goes through a maximum and declines to zero after 20% weight loss.
The product is polyphosphoric acid, a hygroscopic glass.
In the final stage above 350 °C (which may be too high a temperature region to influence some polymers), the polyphosphoric acid structure is fragmented with the formation of low volatility products.
The effects of APP are therefore likely to be due to one or more of these: evolution of NH3 and H2O, production of polyphosphoric acid or acidic species derived from it, and the glassy state of the intermediate decomposition product.
When PMMA is heated with APP, chemical changes in the PMMA occur only above 260 °C in the heating programme, i.e. after NH3 and H2O evolution has ceased and polyphosphoric acid is present.
The observed effects are believed to be due to mobile fragmentation products rather than the crosslinked polyphosphoric acid itself.20
The primary effect is to cause ester groups to be converted to anhydride rings, a small concentration of which is sufficient to interfere significantly with the depolymerization process.
Thus the production of monomer (which is the volatile fuel in a fire situation) is slowed down.
When the temperature is increased, the products include, in addition to monomer, methanol, CO2 and CO.
There is therefore a close parallel with the behaviour of PMMA in other acid-releasing environments, such as blends with polychloroprene.
The application of ammonium polyphosphate (APP) in different types of commodity thermoplastic composites (polyethylene, polypropylene (PP), polystyrene (PS), poly(methyl methacrylate) (PMMA) and poly(ethylene terephthalate) (PET)) have been discussed in terms of mechanical properties, morphologies and thermal properties.
In addition, engineering thermoplastics such as acrylonitrile-butadiene-styrene (ABS), polyamides and poly(vinyl alcohol) (PVOH) and their composites added with APP and other additives were analyzed as well.
It was suggested that improvement of mechanical properties and morphologies of the thermoplastic composites could be made possible with appropriate amount of APP and other additives such as montmorillonite (MMT), pentaerythritol (PER) and different types of layered double hydroxide (LDH). Furthermore, thermal properties such as limiting oxygen index (LOI) values together with cone calorimetry and thermogravimetric analysis (TGA) performance could be enhanced through optimum combination of APP, PER and melamine which functions as intumescent flame retardant (IFR).
APP-based flame retardants have been sold in the U.S., Europe, and Asia for several years.
In the U.S., they are used in the treatment of commercial furniture upholstery, automotive interior fabrics, draperies, and in other applications.
Outside the U.S., APPs are also used as flame retardants in commercial furniture upholstery.
Water-soluble forms of APPs are approved for use in food as a sequestrant and emulsifier.
Both LR2 and LR4 are used for semi-durable, flame-retardant (FR) application.
Water-soluble LR2 is applied to cellulose-rich upholstery fabrics.
Less-soluble LR4 is applied to fabrics as a latex back-coating.
Phosphorus is essential in human physiology.
Phosphate is a structural component of bones and teeth and is essential in many enzymatic processes.
AMMONIUM POLYPHOSPHATE
Ammonium salt of phosphoric acid. It is a high molecular weight fire retardant.
To achieve a synergistic effect, ammonium polyphosphate is added to the formulation of fire retardant coatings together with pentaerythritol or melamine.
ATAMAN KIMYA offers supplies of ammonium polyphosphate for the paint and varnish industry and the production of coatings for use in the production of such final products as:
intumescent fire-resistant coatings, for polyolefins (polypropylene, polyester and thermoplastic polyolefins)
polyurethane foams (hard, elastic and TPU)
thermosetting resins (epoxy, phenolic and unsaturated polyesters)
thermoplastic
textile coverings
paints
plywood
Ammonium Polyphosphate Exflam APP-201
Ammonium Polyphosphate Kylin APP-201
AMMONIUM POLYPHOSPHATE
Description:
Ammonium polyphosphate II crystalline phase.
Application:
intumescent fire-resistant coatings, for polyolefins (polypropylene, polyester and thermoplastic polyolefins)
polyurethane foams (hard, elastic and TPU)
thermosetting resins (epoxy, phenolic and unsaturated polyesters)
thermoplastic, textile coatings, paints, plywood.
CHEMICAL NAME
ammonium salt of polyphosphoric acid
CAS
68333-79-9
APPLICATIONS
Fire retardant coatings
AMMONIUM POLYPHOSPHATE
Description:
Ammonium polyphosphate II crystalline phase. Ammonium Polyphosphate is an environmentally friendly flame retardant with nitrogen structure and halogen free.
Properties:
high degree of polymerization
good heat resistance
low hygroscopicity.
This product is a highly effective inorganic flame retardant.
Application:
for the production of fire retardant intumescent paints, varnishes and sealants for coatings of metal structures, cables and wood
in the production of products on a wooden basis (chipboard, fiberboard, plywood)
in the synthesis of a wide range of resins and plastics with reduced combustibility, flammability, smoke-forming ability, toxicity of combustion products and with reduced flame spread over the surface
in the production of fire-resistant compounds based on rubbers, rubbers, artificial leather, lubricants.
Ammonium polyphosphate commercially produced by Clariant, (former business area of Hoechst AG), Budenheim and other sources is an inorganic salt of polyphosphoric acid and ammonia
containing both chains and possibly branching. Its chemical formula is [NH4 PO3]n(OH)2 showing that each monomer consists of an orthophosphate radical of a phosphorus atom with three
oxygens and one negative charge neutralized by an ammonium cation leaving two bonds free to polymerize. In the branched cases some monomers are missing the ammonium anion and instead
link to three other monomers.
The properties of ammonium polyphosphate depend on the number of monomers in each molecule and to a degree on how often it branches. Shorter chains (n<100) are more water sensitive and less thermally stable than longer chains (n>1000),[1] but short polymer chains (e.g. pyro-, tripoly-, and tetrapoly-) are more soluble and show increasing solubility with increasing chain length.
Ammonium polyphosphate can be prepared by reacting concentrated phosphoric acid with ammonia.
However, iron and aluminum impurities, soluble in concentrated phosphoric acid, form gelatinous precipitates or "sludges" in ammonium polyphosphate at pH between 5 and 7.
Other metal impurities such as copper, chromium, magnesium, and zinc form granular precipitates.
However, depending on the degree of polymerization, ammonium polyphosphate can act as a chelating agent to keep certain metal ions dissolved in solution.
Ammonium polyphosphate is used as a food additive, emulsifier, (E number: E545) and as a fertilizer.
Ammonium polyphosphate (APP) is also used as a flame retardant in many applications such as paints and coatings, and in a variety of polymers: the most important ones are polyolefins, and particularly polypropylene, where APP is part of intumescent systems.[6] Compounding with APP-based flame retardants in polypropylene is described in.Further applications are thermosets, where APP is used in unsaturated polyesters and gel coats (APP blends with synergists), epoxies and polyurethane castings (intumescent systems).
APP is also applied to flame retard polyurethane foams.
Ammonium polyphosphates as used as flame retardants in polymers have long chains and a specific crystallinity (Form II).
They start to decompose at 240 °C to form ammonia and phosphoric
acid. The phosphoric acid acts as an acid catalyst in the dehydration of carbon-based poly-alcohols, such as cellulose in wood.
The phosphoric acid reacts with alcohol groups to form heat-unstable phosphate esters.
The esters decompose to release carbon dioxide and regenerate the phosphoric acid catalyst.
In the gas phase, the release of non-flammable carbon dioxide helps to dilute the oxygen of the air and flammable decomposition products of the material that is burning.
In the condensed phase, the resultant carbonaceous char helps to shield the underlying polymer from attack by oxygen and radiant heat.
Use as an intumescent is achieved when combined with starch-based materials such as pentaerythritol and melamine as expanding agents.
The mechanisms of intumescence and the mode of action of APP are described in a series of publications.
Ammonium polyphosphate is an inorganic salt of polyphosphoric acid and ammonia containing both chains and possibly branching.
The properties of ammonium polyphosphate depend on the number of monomers in each molecule and to a degree on how often it branches.
Shorter chains (n < 100) are more water sensitive and less thermally stable than longer chains (n > 1000).
Consequently, short polymer chains and oligomers (e.g. pyro-, tripoly-, and tetrapoly-) are more soluble and show decreasing solubility with increasing chain length.
Ammonium polyphosphate (APP) is used as a flame retardant in many applications such as paints and coatings, and in a variety of polymers: the most important ones are polyolefins, and particularly polypropylene, where APP is part of intumescent systems.
Compounding with APP-based flame retardants in polypropylene is described in.
Further applications are thermosets, where APP is used in unsaturated polyesters and gel coats (APP blends with synergists), epoxies and polyurethane castings (intumescent systems).
Ammonium polyphosphates as used as flame retardants in polymers have long chains and a specific crystallinity (Form II).
They start to decompose at 240 °C to form ammonia and polyphosphoric acid.
The phosphoric acid acts as a catalyst in the dehydration of carbon-based poly-alcohols, such as cellulose in wood.
The phosphoric acid reacts with alcohol groups to form heat-unstable phosphate esters.
The esters decompose to release carbon dioxide and regenerate the phosphoric acid catalyst.
In the gas phase, the release of non-flammable carbon dioxide helps to dilute the oxygen of the air and flammable decomposition products of the material that is burning.
In the condensed phase, the resultant carbonaceous char helps to shield the underlying polymer from attack by oxygen and radiant heat therefore preventing the pyrolysis of the substrate.
Use as an intumescent is achieved when combined with polyalcohols such as pentaerythritol and melamine as expanding agent.
The mechanisms of intumescence and the mode of action of APP are described in a series of publications.
Due to its uncritical toxicological and environmental profile, ammonium polyphosphate has the potential to widely substitute halogen-containing flame retardants in a series of applications like flexible and rigid PUR-foam and thermoplastics.
Soluble ammonium polyphosphate (SAPP) is employed to prepare flame retardant semirigid polyurethane foam (SPUF) using water as blowing agent.
The flame retardant property of SPUF is evaluated by limiting oxygen index (LOI) and horizontal burning test
Polyurethane foam is regarded as a versatile polymeric material for its comparatively excellent properties such as low density, high specific strength, great insulation, large specific surface area, and good sound-absorbing performance.
Polyurethane foam is more easily burned compared to other foams since there are many easily decomposing urea bonds in it.
Thus, it is necessary to improve the flame retardant property of polyurethane foam
Ammonium polyphosphate (APP), as inorganic phosphorus flame retardant with nitrogen-phosphorus synergistic intumescent effect, has the advantages of thermal stability and lasting effect.
APP can also improve the mechanical properties of the material, so it is often used with other flame retardants, and the most common APP flame retardant studied by researchers is form II, of which the polymerization degree is greater than 1000.
In this paper, the water blown SPUF is synthesized only with soluble ammonium polyphosphate (SAPP) with a low polymerization degree.
Our aim is to study the effect of SAPP on the thermal degradation, the flame-resistant, and the mechanical properties of the SPUF.
Ammonium Polyphosphate (APP), Cas No 68333-79-9, is an environment-friendly and halogen-free flame retardant. APP is the main constituent of many intumescent flame retardant systems: coatings, paints and engineering plastics.
For the chemical point of view, Ammonium Polyphosphate is an inorganic salt of polyphosphoric acid and ammonia. Depending on the polymerization degree, there are two main families of ammonium polyphosphate: Crystal phase I APP (or APP I), and Crystal phase II APP (or APP II).
- APP phase I has a short and linear chain (n < 100), it is more water sensitive (hydrolysis) and less thermally stable; actually it begins to decompose at temperatures above 150 °C.
- The second family of Ammonium polyphosphate is the APP Phase II; which has an high polymerization degree, with n>1000, its structure is cross linked (branched), and it is an high-quality non-halogenated flame retardant.
APP phase II, Ammonium polyphosphate, has an higher thermal stability (the decomposition starts at approximately 300°C) and lower water solubility than APP I.
Tecnosintesi APP phase II is a fine-particle ammonium polyphosphate which has been developed in accordance with requirements of all main European end-users.
The product is suitable for water and solvent based intumescent coatings.
It has low water solubility which makes it useful in application where the product is exposed to high humidity conditions or water.
Our Ammonium Polyphosphate contains 72.5% of phosphorus (as P2O5) which makes it a very effective fire retardant.
APP phase II is probably one of the most effective non-halogen fire retardants in the market.
Main Applications:
Solvent based and Water based intumescent coatings.
Flame retardant for polyurethanes.
Flame retardant for unsaturated polyesters.
Flame retardant for epoxies.
Flame retardant for acrylics.
Ammonium polyphosphate (APP) is an organic salt of polyphosphoric acid and ammonia.
As a chemical, it is non-toxic, environmentally friendly and halogen-free.
It is most commonly used as a flame retardant, selection of the specific grade of ammonium polyphosphate can be determined by the solubility, Phosphorus content, chain length and polymerization degree.
The chain length (n) of this polymeric compound can be linear or branched. Depending on the polymerization degree, there are two main families of ammonium polyphosphate: Crystal phase I APP (or APP I), and Crystal phase II APP (or APP II).
APP phase I has a short and linear chain (n < 100), it is more water sensitive (hydrolysis) and less thermally stable; actually it begins to decompose at temperatures above 150 °C.
The second family of Ammonium polyphosphate is the APP Phase II; which has an high polymerization degree, with n>1000, its structure is cross linked (branched), and it is an high-quality non-halogenated flame retardant.
APP phase II, Ammonium polyphosphate, has an higher thermal stability (the decomposition starts at approximately 300°C) and lower water solubility than APP I.
Ammonium polyphosphate is a specialty chemical that finds many different uses in key industries.
Ammonium Polyphosphate, is an environment-friendly and halogen-free flame retardant. It is the main constituent of many intumescent flame retardant systems: coatings, paints and engineering plastics. It is used to prepare 20% Phosphorous/Nitrogen containing flame retardants, it can be used solely or in conjunction with other materials in the flameproof treatment for textiles, papers, fibers and woods. Special treatment can be used to prepare 50% high concentration flameproof formulations required for special applications.
The most common ammonium polyphosphate fertilizers have a N-P2O5-K2O (nitrogen, phosphorus and potassium) composition of 10-34-0 or 11-37-0. Polyphosphate fertilizers offer the advantage of a high nutrient content in a clear, crystal-free fluid that remains stable within a wide temperature range and stores well for long periods. A variety of other nutrients mix well with polyphosphate fertilizers, making them excellent carriers of micronutrients typically needed by plants.
Description
Ammonium polyphosphates are liquid fertilizers with compositions up to 11-37-0, manufactured by the reaction of anhydrous ammonia with superphosphoric acid. Superphosphoric acid is made by the concentration of regular wet-process acid up to P2O5 concentrations of 78%. Granular polyphosphates suitable for bulk blending are made by reacting ammonia with regular wet process acid of 52% P2O5 content and using the heat of reaction to drive off water to produce a phosphate melt of 10-43-0, with about 40% of the phosphorus in the polyphosphate form.
Exolit® AP 435 is a fine-particle ammonium polyphosphate (phase II) optimized for low viscosity in aqueous suspension and intumescent coatings.
The product is largely insoluble in water and completely insoluble in organic solvents. It is colourless, non-hygroscopic and non-flammable.
Benefits
Optimized for low viscosity in aqueous suspension, low water solubility and low acid number
Non-halogenated flame retardant with favorable environmental and health profile
Particularly suitable as an ”acid donor” for intumescent coatings thanks to its low water solubility. Steel structures coated with intumescent paints can meet the requirements of fire resistance classes specified in EN, DIN, BS, ASTM and others.
Their application on wood or plastics enables these materials to qualify for Building Material Class B (DIN EN 13501-1)
Imparts a good flame-retardant effect to adhesives and sealants when it is incorporated into the base formulation at the rate of 10 - 20%
Suitable non-halogenated flame retardant for polyurethane foams.
PUR Foams with Exolit® AP 435 can be recycled
Excellent flame-retardant effect in cellulose-containing materials such as paper and wood products.
With chipboard products, the DIN EN 13501-1 classification can be achieved by adding 15 - 20 % Exolit® AP 435
An essential component in intumescent formulations for thermoplastics, particularly polypropylene, for which the classification UL 94-V0 is specified for applications in the electrical sector
In the case of thermosets like epoxy resins and unsaturated polyester resins, it paves the way for the production of lightweight components with low solids content
(Bio-)degradable by breaking down to naturally occurring phosphate and ammonia
Flame retardants help to save lives by slowing down or stopping the spread of fire or reducing its intensity.
Also called fire retardants, they are used in anything from phones and curtains to car seats and buildings.
If a fire starts, they may be able to stop it completely – or slow it down and so provide precious extra time for escape.
Clariant’s flame retardants are produced to modern standards in Germany, Switzerland and China.
Their brand name Exolit® has become a byword for sustainable fire safety.
Intumescent flame retardant systems
Mode of action: formation of a voluminous, insulating protective layer through carbonization and simultaneous foaming
Intumescent systems puff up to produce foams. They are used to protect combustible materials such as plastics or wood, and those like steel, which lose their strength when exposed to high temperatures, against the attack of heat and fire.
Basically, intumescent flame retardant systems consist of the following:
1. "Carbon" donors (e.g. polyalcohols such as starch, pentaerythritol)
2. Acid donors (e.g. ammonium polyphosphate)
3. Spumific compounds (e.g. melamine)
Process of intumescent mechanism
1. Softening of the binder/polymer (e.g. polypropylene)
2. Release of an inorganic acid (e.g. ammonium polyphosphate)
3. Carbonization (e.g. of polyalcohols)
4. Gas formation by the spumific compound (e.g. melamine)
5. Foaming of the mixture
6. Solidification through cross-linking reactions
Exolit AP 462
Micro encapsulated APP (phase II) with extremely low water solubility
Product Description
Exolit AP 462 is a product based on ammonium polyphosphate. The crystal modification is phase II.
It is manufactured from ammonium polyphosphate by micro-encapsulation
with melamine resin according to Clariant’s own method.
Exolit AP 462 is a fine-particle white powder with very low solubility in water, even at elevated temperatures. It is
completely insoluble in organic solvents. The product is non-hygroscopic and non-flammable.
Benefits
Extremely low water solubility
Completely insoluble in organic solvents, non-hygroscopic and non-flammable
Even lower viscosity in aqueous suspension, lower heat stability in the temperature range > 300 °C and improved powder flowability in comparison to Exolit® AP 422
Can be used for all applications where ammonium polyphosphate is suitable
Can be used advantageously in intumescent coatings where the ammonium polyphosphate is required to have extremely low water solubility and where lower heat
stability at temperatures above 300 °C contributes to more rapid foaming of the coating
Particularly suitable as an ”acid donor” for intumescent coatings thanks to its low water solubility.
Steel structures coated with intumescent paints can meet the requirements of fire resistance classes specified in EN, DIN, BS, ASTM and others.
The application of APP based intumescent coatings on wood or plastics enables these materials to qualify for Building Material Class B (DIN EN 13501-1)
Imparts a good flame-retardant effect to adhesives and sealants when it is incorporated into the base formulation at the rate of 10 - 20%
Suitable non-halogenated flame retardant for polyurethane foams
Excellent flame-retardant effect in cellulose-containing materials such as paper and wood products
With chipboard products, the B classification according to DIN EN 13501-1 can be achieved by adding 15 - 20%
Casting resins based on epoxy resins or unsaturated polyester resins achieve the classification UL94-V0
Non-halogenated flame retardant with favorable environmental and health profile
Applications
APP can be used for all applications ammonium polyphosphate is suitable for.
In cases where a specific phosphorus content is required to obtain the desired effect, the lower phosphorus content of APP should be compensated by increasing the amount of product added.
Exolit AP 462 can be used advantageously in intumescent coatings where the ammonium polyphosphate is required to have extremely low water solubility and where lower heat stability at temperatures above 300 °C contributes to more rapid foaming of the coating.
Intumescent coatings
On account of its low water solubility, APP is particularly suitable as an ”acid donor” for intumescent coatings.
Other essential components of intumescent systems include a binder, a carbon donor (e.g. pentaerythritol) and a blowing agent (e.g. melamine).
On exposure to flame, the intumescent coatings form a carbonaceous foam which effectively shields the underlying material from temperature increases.
Steel structures coated with intumescent paints can meet the requirements of fire resistance classes specified in EN, DIN, BS, ASTM and others.
The application of APP based intumescent coatings on wood or plastics enables these materials to qualify for Building Material Class B (DIN EN 13501-1).
APP imparts a good flame-retardant effect to adhesives and sealants when it is incorporated into the base formulation at the rate of 10 - 20 %.
Polyurethane foams
APP is a suitable non-halogenated flame retardant for polyurethane foams.
If handling of APP as a solid is not possible we recommend the dosage of the flame retardant by preparing an APP/polyol-suspension.
Because of the low acid number of APP it is also possible to incorporate this flame retardant in an APP/isocyanate suspension.
To prevent the solid from settling the APP suspensions should be stirred or circulated by pump.
Other applications
APP has an excellent flame-retardant effect in cellulose-containing materials such as paper and wood products.
With chipboard products the B classification according to DIN EN 13501-1 can be achieved by adding 15 - 20 % APP.
Casting resins based on epoxy resins or unsaturated polyester resins achieve the classification UL94-V0 with APP.
Packaging and Handling
Delivery form
White powder
Packaging
Exolit AP 462 is packed in 40 x 25 kg-paper bags (polyethylene inliner) net per 1.000 kg-pallet, shrink-wrapped.
Exolit AP 462 can also be supplied in a variety of big bags,shrink-wrapped.
Storage
Minimum shelf life is 12 months from the date of shipping when stored according to the recommended conditions.
APP is a white powder, free of visible foreign matter used as a fire retardant additive.
It is composed of Ammonium polyphosphate (APP) CAS NO. 68333-79-9.
APP is an effective fire retardant additive for applications such as: intumescent paints and coatings, both water-based and solvent-based.
It can also be applied to intumescent mastics, caulks, putties, sealants, epoxies, films and adhesives, as well as polymer systems, including those based on polyethylene, polypropylene, polyurethane, rubber, acrylics and polyterephthalates.
Building materials such as wall coverings, ceiling tiles, roofing products, wall panels, wood chip board and composites can also be used with the application of APP.
For Paints and Coatings
Intumescence
Our range of flame retardant additives are based on the mechanism of intumescence. An intumescent paint or coating will foam up to create an insulating carbon based char which protects and slows the heating of the material it is applied to.
The protective layer also prevents smoke release.
Intumescent coatings begin to foam and carbonise at about 200 ºC to create a thermally insulated layer.
This can delay the rise to the critical temperature limit by several hours.
Intumescence requires three main ingredients:
ACID SOURCE— Catalyst for the intumescence, Ammonium Polyphosphate
CARBON SOURCE—a base for the char, usually a polyalcohol such as pentaerythritol.
BLOWING AGENT—blows/bubbles the carbonaceous char from the surface causing a foam.
We specialize in supplying various grade of ammonium polyphosphate and complimentary products.
Ammonium polyphosphates are key ingredients of intumescent coatings.
They act as charring catalysts and influence the performance and stability of the finished coating.
Ammonium polyphosphates ensure stable foaming and protect steel structures from collapsing.
In addition, oxygen transmission is prevented and the spread of toxic fumes during the fire are inhibited.
The use of APP leads to non-toxic, environmentally-friendly fire protection. Choosing the correct APP is important.
ATAMAN's Series: Fire Protective Ingredients
Intumescent coatings are the ideal fire-protection solution for applications such as paints and coatings on the steel structures of buildings.
ATAMAN's ingredients and special compounds ensure the best incorporation into the various coating matrices.
Ammonium polyphosphates (APP) are key ingredients for intumescent coatings.
They act as charring initiators and influence the performance and stability of the finishing coating.
The functional coated grades combine the compatibility to various coating matrices designed for different requirements.
ATAMAN's intumescent ingredients combine different multiple functional components for steel, textile, wood coatings, sealants and adhesives
Antimony Trioxide (Sb2O3) is used as a synergist to halogen based flame retardants.
Halogen based systems work in the gas phase. When a fire is burning, the energy is so great that the fuel and water produced in the combustion reaction are broken down further into more reactive free radical species.
In fire, halogenated flame retardants release less reactive radicals and react to give non-combustible gases decreasing the fuel for the fire to burn further.
Antimony Trioxide forms halogen halides and oxyhalides which are highly volatile and transport the halides into the gas phase.
polyphosphoric acids ammonium salts
APP
APP-0
XAP-01
APP-3
APP-1
ammonium polyphosphate flame retardant
Ammonium polyphosphate
Water-SolubleAmmoniumPolyphosphate
CrystallinePhaseIiAmmoniumPolyphosphate
Ammonium Polyphosphate (APP)
Amyloid β/A4 Precursor Protein Fragment 328-332
APP1000 ( non-coated APP)
APP1001 (Melamine Coated APP)
APP1002 (Silicone Coated APP)
APP50 ( non-coated APP)
AMoMoniuM poly phoaphate
APP Ⅰ
AMMoniuM Polyphosphate(HONOR APP-HS)
AMMoniuM Polyphosphate(HONOR APP-HM)
Anti-Aminopeptidase P3 antibody produced in rabbit
Anti-APP3 antibody produced in rabbit
Anti-Putative Xaa-Pro aminopeptidase 3 antibody produced in rabbit
Anti-X-Pro aminopeptidase 3 antibody produced in rabbit
Anti-XPNPEP3 antibody produced in rabbit
XPNPEP3
Ammonium Polyphosphate N>1000
Polyphosphoric acids ammonium salt
FR-APP
Ammonium polyphosphate (Phase II n>
68333-79-9
69333-79-9
98333-79-9
6833-79-9
NH4PO3n
NH4n2PnO3n1
Phosphorus Series
Flame retardant
Industrial/Fine Chemicals
UVCBs-polymer