The difference between FKM and Silicone rubber
There are significant differences between fluoroelastomer and Silicone rubber in several aspects, and the following is a detailed introduction and comparison of the two types of rubber:
Material sources and basic characteristics
Material source: Fluoroelastomer is a polymer material with fluoride as a raw material.
Basic characteristics: high thermal stability, corrosion resistance, high durability, and other characteristics. The density is usually around 1.8, with excellent oil resistance and high strength.
Material source: Silicone rubber is an inorganic polymer material, the backbone is composed of silicon and oxygen atoms alternately, and there are usually two organic groups attached to the silicon atoms.
Basic characteristics: good chemical stability, thermal stability, low-temperature performance, and acid and alkali resistance. The density is about 1, it is not resistant to oil, and the strength is relatively low.
Temperature resistance
FKM
It has excellent high-temperature resistance and can be used for a short time at 300°C, and some varieties such as 246 fluoroelastomers can still maintain good elasticity at higher temperatures.
It also has good low-temperature resistance, but it is slightly inferior to Silicone rubber.
Silicone rubber
It has outstanding resistance to high and low temperatures and can operate in a wide temperature range from -100°C to 350°C.
Silicone rubber, which is properly matched, retains its elasticity for long periods at high temperatures.
Oil and solvent resistance
FKM
The oil resistance is very good, and it is the best among oil-resistant rubbers.
Resistant to a wide range of solvents and chemicals.
Silicone rubber
It is not resistant to oil but also less resistant to aliphatic and aromatic solvents.
Fields of application
FKM
It is mostly used in oil-resistant, corrosion-resistant, and high-temperature-resistant environments, such as sealing industrial pipelines, oil seals, and O-rings in the automobile and motor vehicle industries, etc.
Silicone rubber
It is often used in high-temperature and heat-resistant places, such as electronics, aerospace, automobiles (non-oil seal parts), pharmaceuticals, and other fields.
It is also widely used in the medical field because of its physiological inertness and the characteristics of not causing blood clotting.
Other features
FKM
It has excellent physical and mechanical properties, such as tear strength, elongation at break, etc.
Excellent weather aging resistance and ozone resistance.
Silicone rubber
It has good air permeability and the highest oxygen permeability rate among synthetic polymers.
Excellent electrical insulating properties with little change when exposed to moisture, frequency changes, or temperature increases.
Low surface energy, low moisture absorption, and good mildew resistance.
In summary, there are significant differences between fluoroelastomer and Silicone rubber regarding the material source, basic characteristics, temperature resistance, oil and solvent resistance, application fields, and other properties. The choice of rubber material depends on the specific environment and needs.
