| Silicone rubber (SR) has good thermal stability, chemical resistance, and environmental stability over a vast temperature range, and offer excellent hydrophobicity and good insulated properties. SR is widely used for high temperature applications, due to the high thermal stability and their resistance to oxidative degradation. This paper aimed at developing high temperature vulcanized (HTV) SR with excellent comprehensive properties, and study the factors which affected the properties of HTVSR by thermogravimetric analysis (TGA), infrared spectrum analysis (FT-IR), scanning electron microscope (SEM) and so on.B,A and C were chosen as heat stabilizer of SR. The results indicated that, B,A and C can improve the heat resistance of SR. B improved the thermal stability of HTVSR significantly by TGA. The compound additive of A,B and C also have good effect, the tensile strength retain 2.0MPa after 380℃×30min heat aging. The mechanism may be related to B prevent main chain reaction of SR molecule with oxygen.The effects of the content and surface modification of fumed silica on properties of HTVSR were studied. Fumed silica improved process properties after surface modification. The tensile strength of SR improved obviously with the increase of fumed silica. HTVSR has the best mechanical properties when the content of fumed silica is 40-45phr, but the thermal stability of SR become worse with the increase of fumed silica. The properties of HTVSR changed with the increase of vulcanized agent,tear-resistant agent and mildew preventive. When the content of vulcanized agent is 0.7phr, tear-resistant agent is 3.0phr, mildew preventive is 1.0phr, the properties of SR reached the maximum values.
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