Abstract: In order to improve the flame retardant performance of silicone rubber foam (SiFs), manganese phytate (PA-Mn) was prepared by direct precipitation method, and Fourier transform infrared spectroscopy, X-ray optoelectronic spectrum and scanning electron microscope.PA-Mn with the mass fraction of 1%, 3%, 5%, 7% and 9% was added to SiFs, and the performance of ultimate oxygen index (LOI) tester, vertical combustion tester (UL-94) and cone thermometer were analyzed. The results show that the PA-Mn prepared by direct precipitation method has high purity. PA-Mn can significantly improve the flame retardant and smoke suppression properties of SiFs. When the addition amount is 3%, the flame retardant and smoke suppression properties of SiFs are the best. The LOI is 28.2%, reaching UL-94 V-0 grade. The peak heat release rate, total heat release and fire growth index are 27.4%, 16.1 % and 36.4% lower than those of pure SiFs, respectively. The fire performance index is 22.2% higher than that of pure SiFs, and the smoke density grade, maximum smoke density and total smoke production are 5.5%, 19.8% and 16.6% lower than those of pure SiFs, respectively.

Key words: silicone rubber foam（SiFS）, phytic acid metal salt, flame retardant, smoke suppression