What is silicone rubber

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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 atoms. Ordinary silicone rubber is mainly composed of silicone links 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 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℃. The heat resistance of silicone rubber is also outstanding. It can work for a long time at 180 ℃. It can withstand a few weeks or more and is still flexible 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 highest oxygen permeability among synthetic polymers. In addition, silicone rubber also has outstanding characteristics of being physiologically inert and not causing coagulation, so it is widely used in the medical field. [1]
Silicone rubber is divided into thermal vulcanization type (high temperature vulcanization silicone HTV), room temperature vulcanization type (RTV), of which room temperature vulcanization type is divided into polycondensation 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, potting material or mold. The thermal vulcanization type has the largest amount, and the thermal vulcanization type is divided into methyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ, the most dosage and product brand), methyl vinyl phenyl silicone rubber PVMQ (low temperature resistance, radiation resistance ), and others include silicone rubber and fluorosilicone rubber.