Ammonium Polyphosphate (Food Grade)
- IUPAC Name
- ammonium polyphosphate
- Molecular Formula
- (NH4PO3)n
- Synonyms & Trade Names
- Ammonium polyphosphate; APP; FR-CROS
- Purity / Assay (%)
- 67% P2O5 min
- Physical Form
- Solid
- Concentration
- Pure substance
Categories
Technical Document
Brief Overview
Ammonium Polyphosphate (APP) is a 100% water-soluble phosphate that is mostly used in plants. APP is an inorganic salt of ammonia and polyphosphoric acid, whose chain length is variable and branched. Short-length APP chains are water sensitive and unstable compared to longer-chain APP. There are two main families of APP Crystal Phase 1 APP (linear structure) and Crystal Phase 11 APP (branched structure). APP is a non-toxic, environmentally friendly material, and it is used as flame retardant as it does not generate smoke due to the unique mechanism of intumescence
Manufacturing Process
APP is prepared by a reaction between concentrated phosphoric acid with ammonia. However, impurities consisting of iron and aluminum are soluble in concentrated phosphoric acid, which forms gelatinous precipitates in APP. In industrials, APP is manufactured by polycondensation between mono ammonium phosphate and urea.