Silicone rubber refers to rubber whose main chain is composed of alternating silicon and oxygen atoms, with two organic groups usually connected to the silicon atoms. Ordinary silicone rubber is mainly composed of silicon oxygen chains containing methyl and a small amount of vinyl groups. Silicone rubber has good low-temperature resistance and can generally still work at -55 ℃. After introducing phenyl, it can reach -73 ℃. The heat resistance of silicone rubber is also outstanding. It can work for a long time at 180 ℃, and can withstand several weeks or longer with elasticity even slightly above 200 ℃. It can withstand high temperatures above 300 ℃ instantly. Silicone rubber has good breathability and the oxygen permeability is the highest among synthetic polymers.

In addition, silicone rubber has outstanding characteristics of physiological inertness and does not cause coagulation, making it widely used in the medical field. Silicone rubber is divided into heat vulcanization type (high-temperature vulcanized silicone HTV) and room temperature vulcanization type (RTV), among which room temperature vulcanization type is further divided into condensation reaction type and addition reaction type. High temperature silicone rubber is mainly used to manufacture various silicone rubber products, while room temperature silicone rubber is mainly used as an adhesive, sealing material, or mold. The heat vulcanization type has the highest usage, which is further divided into methyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ, with the highest usage and product grade), methyl vinyl phenyl silicone rubber PVMQ (resistant to low temperature and radiation), as well as other types such as silicone rubber and fluorosilicone rubber.

There are several factors that affect the performance of silicone rubber materials:
1. The introduction of benzene can improve the high and low temperature resistance of silicone rubber; The introduction of trifluoropropyl and cyano groups can improve the temperature and oil resistance of silicone rubber;
2. Mainly using high molecular weight polyvinylsiloxane as raw rubber, mixed with reinforcing fillers, vulcanizing agents, etc., and vulcanized into elastomers under heating and pressure, can greatly improve the temperature resistance of silicone rubber;
3. The addition of white carbon black can increase the strength of silicone rubber by tens of times;
4. Various additives can endow silicone rubber with special properties;
5. Introduce phenylene groups on the main chain. Due to the introduction of the active group vinyl, the crosslinking efficiency of peroxide crosslinking in silicone rubber has been greatly improved.