The invention discloses a self-inflaming-retarding
epoxy resin curing agent containing
phosphorus-
nitrogen and a preparation method thereof and relates to
epoxy resin curing agents. The method comprises the steps that N-phenyl-1, 4-phenylenediamine and 4-hydroxy
benzaldehyde are added into a container provided with a condensation
pipe and a stirrer for reacting with first
solvent, the
reaction system is filtered, and solids obtained after the filtering are washed and dried, so that an intermediate body is obtained; the intermediate body, DOPO and second
solvent are added into a container provided with a condensation
pipe and a stirrer for reacting, the
reaction system is filtered, and solids obtained after the filtering are washed and dried, so that the self-inflaming-retarding
epoxy resin curing agent containing the
phosphorus-
nitrogen is obtained; or alternatively, the N-phenyl-1, the 4-phenylenediamine, the 4-hydroxy
benzaldehyde and the DOPO are added into a container provided with a condensation
pipe and a stirrer sequentially for reacting with
solvent, the
reaction system is filtered, and articles obtained after the filtering are washed and dried, so that the self-inflaming-retarding epoxy resin curing agent containing the
phosphorus-
nitrogen is obtained. The curing agent contains two active imino groups, one active hydroxyl group and P and N synergistic
flame retardant elements simultaneously and can be used for epoxy resin curing and inflaming retardation.