Abstract: Ammonium polyphosphate, pentaerythritol, urea and polyester resin were used as the intumescent flame retardants agent of acid source, carbon source, gas source and film former.Exploring the influence of each component on the flame retardant performance in primary and secondary order based on orthogonal experiment, the small chamber combustion and limit oxygen index test, measure the effect of the intumescent flame retardant under different formulas.The results show m(ammonium polyphosphate)>m(polyester resin)>m(urea)>m(pentaerythritol),which is 9# formula A3B3C2D1, samples treated by this formula, the oxygen index obviously rise to 38%.At the same time, the combustion process was analyzed through TG and SEM analysis, and the mechanism of the intumescent flame retardant was explained.

Key words: orthogonal experiment;TG analysis;intumescent flame retardant