Abstract: A novel flame retardant was synthesized from phosphorus oxychloride, pentaerythritol, and dichloromethane, with its chemical structure confirmed by FTIR. Its flame retardant property was characterized through thermogravimetry, limiting oxygen index, and intumescent character. After combustion in Muffle Furnaces the volume of the flame retardant was expanded by 27 times. Thermogravimetry up to 800 ℃ showed that a charred layer was formed which amounted to 16 % of the original weight. Loaded with 10 mass % of the flame retardant, the limiting oxygen index (LOI) of populus reached 36 %, 18 % higher than the plain sample.

Key words: phosphorus oxychloride, pentaerythritol, chloride bispirocyclic pentaerythritol phosphate ester, intumscent flame retardant