The invention discloses a
tannic acid-based
flame retardant, a preparation method thereof and application of the
tannic acid-based
flame retardant in semi-rigid
polyurethane foam, and belongs to the technical field of
flame-retardant materials. According to the flame retardant,
tannic acid,
melamine polyphosphate and
zinc ions are compounded to form a novel synergistic flame-retardant
system. The preparation method comprises the following steps: dispersing MPP and
paraformaldehyde in water, adding tannic acid for reaction, introducing
zinc chloride for coordination crosslinking, and finally washing and
drying to obtain the product. According to the flame retardant, a
polyphenol structure of tannic acid is used for enhancing compatibility and
dispersity with a
polyurethane matrix, under the synergistic effect of the tannic acid,
phosphorus-
nitrogen flame-retardant components and
metal ions, formation of a compact
carbon layer is effectively promoted, and the flame-retardant efficiency is remarkably improved. When being applied to semi-rigid
polyurethane foam, the
composite material can greatly improve the limit
oxygen index of the material, the limit
oxygen index reaches up to 29.4% and passes the UL-94 V-0 grade, and meanwhile, the excellent
mechanical property is kept.