Polyphosphate salt of a 1,3,5-triazine compound with a high degree of condensation and its use as flame retardant in polymer compositions

摘要

Salt of a 1,3,5-triazine compound with polyphosphoric acid with a virtually linear structure, with the number average degree of condensation n being higher than 20, the content of the 1,3,5-triazine compound being higher than 1.1 mole per mole of phosphorus atom and the pH of a 10% slurry in water being higher than 4.5. Further, a process for the preparation of the polyphosphate salt of a 1,3,5-triazine compound with a number average degree of condensation n that is higher than 20, by converting a 1,3,5-triazine compound with orthophosphoric acid at room temperature into the phosphate of the 1,3,5-triazine compound, after which this salt is converted at elevated temperature into a polyphosphate of the 1,3,5-triazine compound, and further flame retardant polymer compositions comprising the polyphosphate salt of a 1,3,5-triazine compound with a number average degree of condensation n higher than 20.