Fluorosilikone

Fluorosilicones, also known as fluorosilicone elastomers (FVMQ), are silicone polymers in which fluorinated side chains, typically trifluoropropyl groups, are incorporated into the siloxane framework. This modification combines the high thermal stability of silicones with the chemical resistance conferred by fluorine, especially against fuels, oils, and many solvents.

In terms of properties, fluorosilicones offer superior resistance to automotive and aviation fuels, lubricants, and certain harsh chemicals compared with standard silicone elastomers. They generally maintain good heat resistance and flexibility over a wide temperature range, but can be stiffer and harder to cure than conventional silicones. Processing and raw material costs are typically higher due to the fluorinated content, and availability can be more limited. Depending on formulation, fluorosilicones can be cured by addition (platinum-catalyzed) systems or peroxide curing, with specialized grades optimized for fuel and chemical contact.

Applications for fluorosilicones focus on environments where exposure to fuels, solvents, or ozone is a concern. They are used for seals, gaskets, O-rings, and valve components in automotive and aerospace fuel systems, chemical processing equipment, and other harsh chemical contact applications. They may be selected for long-term stability in contact with hydrocarbon fuels or in environments where conventional silicones would swell or degrade.

Limitations include higher cost, more restricted supplier bases, and sometimes reduced low-temperature performance or mechanical toughness compared with non-fluorinated silicones. Proper compatibility testing is advised for specific chemicals and operating conditions.