Flora Silicone O-Ring

1. Oil Resistance, Solvent Resistance, Chemical Resistance

Compared to methyl vinyl silicone rubber, fluorosilicone rubber exhibits excellent oil resistance, solvent resistance, and chemical resistance. Even compared to fluororubber, it has good oil and solvent resistance. In the same environment, considering temperature and immersion time, it can be said that fluorosilicone rubber is an elastic body resistant to non-polar media between -68 °C and 232 °C. The resistance of fluorosilicone rubber to methanol-containing gasoline is also relatively good; even in a mixed gasoline/methanol system (85% volume / 15% volume), the hardness, tensile strength, and volume changes of vulcanized rubber are minimal. After a 500-hour impregnation test, the physical properties remain almost unchanged.

2. Heat Resistance

The high-temperature decomposition of fluorosilicone rubber is similar to that of silicone rubber, involving side chain oxidation, main chain breakage, side chain thermal decomposition, and various compound reactions. Since decomposition products can also cause main chain breakage, its heat resistance is generally lower than that of silicone rubber, with oxidative aging starting at 200 °C. However, by adding small amounts of heat stabilizers such as iron, titanium, or rare earth oxides, it can be significantly improved, providing sufficient heat resistance even at 250 °C. The effect of temperature on fluorosilicone rubber is greater than on silicone rubber but less than on fluororubber. Studies abroad have examined the service life of fluorosilicone rubber at 150 °C × 2000 hours, 175 °C × 5000 hours, and 200 °C × 4000 hours, with results ranking it second after methyl vinyl silicone rubber.

3. Cold Resistance

Fluorosilicone rubber and ordinary silicone rubber have good low-temperature performance. As a linear polymer with a soft Si-O main chain, fluorosilicone rubber has better low-temperature properties than fluororubber, which has a CC main chain. Among them, fluorosilicone rubber (LS-2370U) exhibits superior low-temperature characteristics, with a brittleness temperature as low as -89 °C, while general fluororubber is around -30 °C.

4. Electrical Performance, Radiation Resistance

The electrical properties of fluorosilicone rubber are similar to those of ordinary silicone rubber, but its unique advantage is that changes under harsh conditions such as high temperature, low temperature, humidity, oil, solvents, chemicals, and ozone are minimal. The radiation resistance of fluorosilicone rubber is not exceptional, but its resistance to radiation aging is better than that of methyl vinyl silicone rubber.

5. Physical and Mechanical Properties

Like ordinary silicone rubber, the mechanical strength (especially tear strength) of vulcanized fluorosilicone rubber is relatively low. Therefore, improving and enhancing the strength of fluorosilicone rubber is an important research topic.

6. Other Properties

Fluorosilicone rubber has excellent weather resistance, maintaining good performance even after 5 years of exposure. Ozone is one of the most common gases generated during elastomer aging, but no cracking or damage was observed in fluorosilicone rubber after dynamic or static tests.

Applications of Fluorosilicone Rubber

Fluorosilicone rubber is an elastomer material that combines the properties of both silicone rubber and fluororubber. Its greatest advantage over methyl vinyl silicone rubber is its oil and solvent resistance; compared to fluororubber, while there is little difference in resistance to alkane solvents, its resistance to aromatic solvents is superior, with only highly polar, small-molecule ketones serving as effective solvents. Fluorosilicone rubber has better heat resistance, cold resistance, and compression set resistance, with physical properties that are less dependent on temperature from low to high ranges, delivering excellent performance. Additionally, low-hardness products can be made without the use of plasticizers. Therefore, as a new high-performance elastomer material, fluorosilicone rubber is widely used.