Silicone rubber refers to the rubber whose main chain is composed of alternating silicon and oxygen atoms, and two organic groups are usually connected to the silicon atom. Ordinary silicone rubber is mainly composed of silicone chain units containing methyl groups and a small amount of vinyl groups. The introduction of phenyl can improve the high and low temperature resistance of silicone rubber, and the introduction of trifluoropropyl and cyano groups can improve the temperature and oil resistance of silicone rubber.
Silicone rubber has good low temperature resistance and can generally still work at -55°C. After the introduction of phenyl, it can reach -73°C. The heat resistance of silicone rubber is also very outstanding. It can work for a long time at 180°C, and can withstand a few weeks or longer even if it is slightly higher than 200°C. It can withstand high temperatures above 300°C instantaneously. Silicone rubber has good air permeability and oxygen transmission rate is the highest among synthetic polymers. In addition, silicone rubber has outstanding properties of being physiologically inert and not causing coagulation, so it is widely used in the medical field.

High temperature performance. The remarkable feature of silicone rubber is high temperature stability. Although the strength of silicone rubber at room temperature is only half of that of natural rubber or some synthetic rubbers, it can still maintain a certain degree of flexibility and recovery at high temperatures above 200 °C. Elasticity and surface hardness, and no significant change in mechanical properties.
1. Low temperature performance. The glass transition temperature of silicone rubber is generally -70 to -50 °C, and the special formula can reach -100 °C, indicating its excellent low temperature performance. This is of great significance to the aviation and aerospace industries.

2. Weather resistance. The Si-O-Si bond in silicone rubber is very stable to oxygen, ozone and ultraviolet rays, and has excellent weather resistance without any additives.

3. Electrical properties. Silicone rubber has excellent insulating properties, corona resistance and arc resistance are also very good.

4. Physical and mechanical properties. The physical and mechanical properties of silicone rubber at room temperature are worse than that of general-purpose rubber, but at a high temperature of 150 °C and a low temperature of -50 °C, its physical and mechanical properties are better than general-purpose rubber.

5. Oil and chemical resistance. Ordinary silicone rubber has moderate oil and solvent resistance.

6. Gas permeability. At room temperature, the air permeability of silicone rubber to air, nitrogen, oxygen, carbon dioxide and other gases is 30-50 times higher than that of natural rubber.

7. Physiological inertia. Silicone rubber is non-toxic, tasteless, odorless, non-adhesive to human tissue, has anticoagulant effect, and has very little reactivity to human tissue. Especially suitable as medical material.