Classification by chemical composition:
Methyl silicone rubber (MQ): It is one of the earliest developed silicone rubbers with good thermal and chemical stability. However, it has low vulcanization activity and large high-temperature compression permanent deformation, which is not suitable for making thick products. It has been gradually replaced by methyl vinyl silicone rubber with better performance.

Methyl vinyl silicone rubber (VMQ): Because it contains a small amount of vinyl side chains, it is easier to vulcanize than methyl silicone rubber. There are more types of peroxides available for vulcanization, and the amount of peroxide can be greatly reduced. It has good process performance and convenient operation. It can be made into thick products. The surface of extruded and calendered semi-finished products is smooth. It is currently a more commonly used HTV silicone rubber.

Methyl vinyl phenyl silicone rubber (PVMQ): It is obtained by introducing phenyl into the molecular chain of vinyl silicone rubber. According to the different phenyl content, it can be divided into low phenyl, medium phenyl and high phenyl silicone rubber. Low phenyl silicone rubber has excellent low temperature resistance; medium phenyl silicone rubber has the characteristics of ablation resistance; high phenyl silicone rubber has excellent radiation resistance.

Fluorosilicone rubber (FVMQ): Fluorinated alkyl groups are introduced into the side chain, which has good heat resistance and excellent oil and solvent resistance. Its low temperature performance is relatively good, but its electrical insulation performance is worse than that of vinyl silicone rubber. When heated above 300°C, toxic gas will be generated.

Nitrile silicone rubber (NVMQ): Nitrile alkyl groups (generally β-nitrile ethyl or γ-nitrile propyl) are introduced into the side chain. The introduction of polar nitrile groups improves the oil and solvent resistance of silicone rubber.