Fluorosilicone is a new material developed on the basis of organosilicon and organofluorine. Fluorosilicone polymer has both high temperature chemical corrosion resistance, oil resistance and excellent high temperature tensile retention and low temperature softness properties of fluorocarbon rubber due to its main chain structure of silicon oxygen bond and side chain structure of fluoroalkyl. Foreign experts believe that fluorosilicone rubber is the only synthetic rubber with oil resistance and solvent resistance used in a wide temperature range of - 68 ℃ - 232 ℃. Fluorosilicone rubber, also known as γ- Trifluoropropylmethylpolysiloxane is a kind of silicone elastomer modified by side chain. Generally, the products made of fluorosilicone rubber not only have the characteristics of general silicone rubber, but also have excellent oil resistance, including fuel oil, engine oil, chemical reagent and solvent. Therefore, fluorosilicone rubber can make up for the lack of oil resistance of ordinary silicone rubber, and can be called the "king of new materials" in silicone elastomer. Due to its excellent oil resistance and heat resistance of silicone elastomer, fluorosilicone rubber is especially suitable for some applications requiring high temperature and fuel resistance, such as seals, rubber tubes, rubber pads, films and impregnated products. It is an indispensable special material for automobile industry, modern military industry, aerospace industry, transportation industry such as automobile and ship, petrochemical industry, and medical and health departments such as artificial organs.


What are the important characteristics of fluorosilicone rubber


Cold resistance


Fluorosilicone rubber has the same low temperature performance as ordinary silicone rubber. Because fluorosilicone rubber is a linear polymer with soft Si-O as the main chain, its low temperature properties are better than those of fluorosilicone rubber with C-C as the main chain. Among them, ls-2370u has better low-temperature properties, and its brittleness temperature is as low as - 89 ℃, while that of ordinary fluorine rubber is about - 30 ℃.


Excellent weather aging resistance


The weather aging resistance of fluorosilicone rubber is very good, even after 5 years of exposure, it still has good performance. Ozone is a very large amount of gas generated during the aging of elastomers, but no cracks or cracks were found in fluorosilicone rubber after dynamic or static tests. In addition, the antifungal, physiological inertia and anticoagulant properties of fluorosilicone rubber are also very good.


Electrical performance and radiation resistance


The electrical properties of fluorosilicone rubber are similar to that of ordinary silicone rubber, but the most valuable thing is that it has little change under harsh conditions such as high temperature, low temperature, humidity, oil, solvent, chemicals and ozone. The radiation resistance of fluorosilicone rubber is not outstanding, but the radiation aging resistance is better than that of methyl vinyl silicone rubber.


Physical and mechanical properties


The mechanical strength (especially tear strength) of fluorosilicone vulcanizate is lower than that of ordinary silicone rubber. Therefore, improving the strength of fluorosilicone rubber is also an important research topic.


Oil, solvent and chemical resistance


Compared with methyl vinyl silicone rubber, fluorosilicone rubber has excellent oil resistance, solvent resistance and chemical resistance; Even compared with fluororubber, it has good oil and solvent resistance. It can be said that fluorosilicone rubber is a kind of non-polar medium resistant elastomer at - 68 ℃ ~ 232 ℃. Even in the gasoline / methanol mixed system, the hardness, tensile strength and volume change of the vulcanizates are very small. After 500 hours of long-term immersion test, the physical properties of the vulcanizates are almost unchanged.


Heat resistance


The high temperature decomposition of fluorosilicone rubber is the same as that of silicone rubber, that is, side chain oxidation, main chain fracture, side chain thermal decomposition and various complex reactions. Because the decomposition products can also cause the main chain fracture, the heat resistance of silicone rubber is usually worse than that of silicone rubber, and it has begun to oxidize at 200 ℃. However, by adding a small amount of heat stabilizers such as iron, titanium, rare earth oxides and so on, it can be significantly improved and has enough heat resistance even at 250 ℃. The effect of temperature on fluorosilicone rubber is larger than that of silicone rubber, but smaller than that of fluorosilicone rubber. The performance of fluorosilicone rubber at 150 ℃ was also studied abroad × 2000h、175℃ × 5000h、200℃ × The service life under the condition of 4000H is second only to that of methyl vinyl silicone rubber.