Abstract: A type of master rubber was prepared using silicone rubber （SR） as a matrix and mullite fiber （MF）， hollow glass microbeads （GB）， 2，5-dimethyl-2，5-di（tert-butylperoxy）hexane， CaCO3， and Fe2O3 as additives. Then， ceramic-retardable flame-retardant silicone rubber composites were prepared by adding Al（OH）3 and Mg（OH）2 at different parts ratios through open mixing and vulcanization. The results indicated that GB played a role of bonding bridge at a high temperature and MF acted as a skeleton in the preparation of the ceramic-retardable flame-retardant silicone rubber composites. The rubber composite containing 30 parts of Mg（OH）2 obtained a tensile strength of up to 4.93 MPa， elongation at break of 1 450.73 %， and a limiting oxygen index of 31.8 vol%. The silicone rubber composite with a thickness of 6 mm could burn for 15min at a frequency of 50 Hz， 5 g acceleration， and a temperature of 1 050 °C without burning through.

Key words: silicone rubber, flame retardant, aluminum hydroxide, magnesium hydroxide