1,3,5-Triazine-2,4,6-triamine monophosphate → HCID 178508833, compound

Participants

Reaction Steps

Melamine polyphosphate and a process for preparing melamine polyphosphate are described, inter alia, in WO 97/44377. According to this reference, melamine polyphosphate having a solubility of 0.01 to 0.10 g per 100 ml water at 25° C., a pH between 2.5 and 4.5, and a melamine/phosphorus molar ratio of between 1.0 and 1.1, may be obtained as a 10 wt % aqueous slurry at 25° C. WO 97/44377 also describes a two-step process for preparing the disclosed melamine polyphosphate slurry. In the first step melamine, urea, and an aqueous orthophosphoric acid solution (containing at least 40 wt % orthophosphoric acid), are mixed to produce a reaction mixture having a melamine/orthophophoric acid molar ratio between 1.0 and 1.5 moles and a urea/orthophophoric acid molar ratio between 0.1 and 1.5 at a temperature between 0 and 140° C. The resulting reaction mixture is then is stirred at a temperature between 0 and 140° C. and dehydrated to produce a powdery product comprising a double salt of orthophosphoric acid with melamine and urea. This powdery product is then heated to between 240 and 340° C. and maintained in this temperature range for between 0.1 and 30 hours while preventing agglomeration to obtain melamine polyphosphate.

Provenance & Evidence