The invention relates to a
phosphorus-
nitrogen-
silicon intumescent flame retardant containing a
triazine ring and a cage structure and a synthesis method of the
intumescent flame retardant. The synthesis method comprises the steps as follows: a
solvent is added to a container,
phosphorus oxychloride is added and stirred to be dispersed, PEPA (1-oxy phospha-4-(
hydroxymethyl)-2,6,7-trioxabicyclo[2.2.2]
octane) and an acid-binding agent are dropwise added step by step, and a PEPA-containing unitary
substituent is obtained; substances with
diamine or dihydric
alcohol are added to the other container and mixed with the
solvent and the acid-binding agent, the PEPA-containing unitary
substituent is slowly dropwise added, and a phosphorous-containing
diamine intermediate is obtained after separation; the
solvent is added to a container provided with a
reflux condenser and the like,
cyanuric chloride is added and stirred to be dispersed, an amino
silane coupling agent and the acid-binding agent are dropwise added step by step, and a
silicon-containing unitary
substituent is obtained; the mixture of the phosphorous-containing
diamine intermediate and the acid-binding agent is slowly dropwise added, cooling, washing and
drying are performed, and a powdery
solid, namely, the
phosphorus-
nitrogen-
silicon intumescent flame retardant containing the
triazine ring and the cage structure, is obtained. The phosphorus-
nitrogen-silicon intumescent flame retardant has the advantages that the flame retardant has certain
polymerization degree, high molecular weight, higher
charcoal forming amount and better
thermal stability, the proportion of acid sources, carbon sources and gas sources in molecular structures is relatively proper and the like.