Fluororubber (FKM) is a type of synthetic rubber containing gas. It is widely used in aerospace, automotive and chemical industries due to its heat resistance, chemical resistance and weather resistance. The following is a detailed introduction to fluororubber.
Characteristics of fluororubber
1. High temperature resistance: fluororubber can be used for a long time at 200°C or even higher temperatures, and some specially formulated fluororubbers can withstand high temperatures of 300°C.
2. Chemical corrosion resistance: They have good corrosion resistance to most chemicals, including oils, fuels, solvents, acids and alkalis.
3. Weather resistance and aging resistance: fluororubber exhibits good aging resistance in environments such as ultraviolet rays, ozone and oxygen.
4. Low gas permeability: fluororubber has good barrier properties to gases and is suitable for sealing and isolation applications.
5. Good mechanical properties: fluororubber has good elasticity, tensile strength and wear resistance.
Common types of fluororubbers
1. Polyvinylidene fluoride (PVDF): has chemical corrosion resistance and mechanical properties, and is commonly used in chemical equipment and pipelines
2. Hexafluoropropylene-vinylidene fluoride copolymer (FKM): is commonly used in high-temperature and oil-resistant seals, such as O-rings and gaskets.
3. Tetrafluoroethylene-propylene copolymer (FEPM): has excellent chemical corrosion resistance and high temperature resistance, and is used in the aerospace field.
4. Perfluoroether rubber (FFKM): has extremely high chemical stability and high temperature resistance, and is a type of oxygen rubber with good performance. It is used for seals in extreme environments.
Synthesis method
The synthesis of fluororubber is mainly carried out by free radical polymerization or emulsion polymerization. Common monomers include vinylidene fluoride (VDF), hexafluoropropylene (HFPQ), tetrachloroethylene (TFE) and perfluoroalkoxy vinyl ether (PAVE).
1. Free radical polymerization: The polymerization of monomers is initiated by an initiator to generate a polymer chain.
2. Emulsion polymerization: The polymerization reaction is carried out in the aqueous phase to obtain well-dispersed polymer particles.
Application areas
1. Automotive industry: used to manufacture oil seals, O-rings, gaskets and fuel system components, providing high temperature and oil resistance.
2. Aerospace: used in fuel systems, hydraulic systems and seals due to its high temperature and chemical corrosion resistance.
3. Chemical industry: used to manufacture corrosion-resistant pipes, pumps and valve seals due to its chemical resistance.
