The combustibility and thermal stability of fire-retardant viscose rayon were evaluated by 45°Slope Burning Method, Limit Oxygen Index(LOI), Differential Scanning Calorimetry(DSC), Thermogravimetry Analysis(TGA). The results indicated that modified fiber could reach the limit oxygen index fire retardant standard(LOI≥28),and fire retardant standard of Japan industry standard JIS 1091-77(Times of ignition≥3 times). The data showed that the fire retardant rayon was a durable fire retardant viscose rayon. The analysis of the fiber's thermal degradation mechanism suggests that the flame retardants play a multi role of catalytic dehydration and carbonization, heat absorption, condensation phase and gas phase flame retardation.
