The invention discloses a DOPO type reactive
flame retardant with a terminal group as an
epoxy group, a preparation method therefor and an application thereof. The preparation method comprises: heating DOPO and a poly(
glycidol)-based compound in a reaction
molar ratio to react in an
organic solvent; and removing the
solvent under reduced pressure, thereby obtaining the reactive
flame retardant which is a
viscous liquid at the
room temperature, contains a DOPO
flame retardant radical and has the terminal group which is the
epoxy group. The flame retardant synthetic method is simple, easy to control, good in
repeatability, high in yield, suitable for enlarged production, and can be used as an end-sealed type flame retardant which is applied to
flame resistance of a
polyurethane material. The flame retardant is applied to the
polyurethane material, so that not only are defects of poor compatibility between the added flame retardant and a
basal body, easy run-off in a using process and the like overcome, but also a complex process for synthesizing polyhydric alcohols by use of a conventional reactive flame retardant is avoided; and the
flame resistance of the material is obviously improved, the
oxygen index of
polyurethane leather is increased to 26-28%, and the flame retardant level can reach level UL94 V-0.