Silicone Elastomers by Radical Polymerization

It has been reported that the dimethyl silicone rubber remains flexible at temperatures as low as 60°C. Partial substitution of methyl groups by phenyl groups extends the low temperature performance to -93°C due to steric hindrance of the polymer chains. Such phenyl silicone rubbers are typically used in aerospace apphca-tions at low temperatures. Crosslinking of poly(methylvinylsiloxane) is accomphshed 

A silicone rubber may also include more than one side group, allowing for different properties. For example, a polymer containing phenyl and vinyl groups would exhibit improved crosslinking as well as low temperature flexibility. 

Fluorosdicones contain polar trifluoropropyl side groups. The advantage of fluorosilicone rubbers is their excellent resistance to both oils and fuels. Moreover, 

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