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        Silicone rubber refers to a rubber whose main chain is composed of silicon and oxygen atoms alternately, and two organic groups are usually connected to the silicon atom. Ordinary silicone rubber is mainly composed of silicone chains 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 still work at -55 ℃. After introducing 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 ℃, and it can withstand elasticity for several weeks or longer when it is slightly higher than 200 ℃. It can withstand high temperatures above 300 ℃ in an instant. Silicone rubber has good air permeability, and the oxygen transmission rate is the highest among synthetic polymers. In addition, silicone rubber has the outstanding characteristics of being physiologically inert and not causing coagulation, so it is widely used in the medical field.

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