(1) high and low temperature resistance

Among all rubbers, silicone rubber has the widest working temperature range (- 100-350 ℃). For example, vinyl silicone rubber or low phenyl silicone rubber with proper coordination can keep elasticity after aging by hot air at 250 ℃ for thousands of hours or 300 ℃ for hundreds of hours; low phenyl silicone rubber vulcanizate can keep elasticity after aging by hot air at 350 ℃ for dozens of hours, and its glass transition temperature is - 140 ℃, and its vulcanizate still has elasticity at - 70-100 ℃. When silicone rubber is used as the heat-resistant coating on the inner wall of rocket nozzle, it can withstand thousands of degrees of high temperature.

(2) ozone aging resistance, oxygen aging resistance, light aging resistance and weather aging resistance
After several years of outdoor exposure in free state, the properties of silicone rubber vulcanizate have no significant change.

(3) the electrical insulation property of silicone rubber vulcanizate changes little when it is damped, frequency changes or temperature increases, and the silica produced after combustion is still insulator. In addition, there are few carbon atoms in the molecular structure of silicone rubber, and carbon black is not used as filler, so it is not easy to scorch in arc discharge, and it is very reliable in high-voltage applications. Its corona resistance and arc resistance are excellent. Its corona resistance life is 1000 times that of polytetrafluoroethylene and 20 times that of fluororubber.

(4) special surface properties and physiological inertia
The surface energy of silicone rubber is smaller than that of most organic materials. It has low hygroscopicity. The water absorption rate of silicone rubber immersed in water for a long time is only about 1%. Its physical properties do not decline, and its mildew resistance is good. It does not bond with many materials and can play an isolation role. Silicone rubber is tasteless, nontoxic, has no adverse effect on human body, has slight reaction with body tissue, and has excellent physiological inertia and aging.

(5) high air permeability
Compared with other high molecular materials, silicone rubber has good permeability. At room temperature, its permeability to nitrogen, oxygen and air is 30-40 times higher than that of NR, and its permeability to gas is selective, for example, its permeability to carbon dioxide is about 5 times that of oxygen.

(6) biomedical performance
Silicone rubber has excellent biomedical properties due to its molecular structure, which has been proved by a large number of animal and human experiments.