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What is fluororubber? Fluorine rubber refers to a synthetic polymer elastomer containing fluorine atoms on the carbon atoms of the main chain or side chain. The introduction of fluorine atoms endows rubber with excellent heat resistance, oxidation resistance, oil resistance, corrosion resistance and atmospheric aging resistance. It has been widely used in aerospace, aviation, automobiles, petroleum and household appliances and other fields. An irreplaceable key material in industry. Since 1943, it has successively developed varieties of polyolefin fluororubber, nitroso fluororubber, tetrapropylene fluororubber, phosphazene fluororubber and perfluoroether rubber. 

Main characteristics of fluororubber 

1. Fluorine rubber has a high degree of chemical stability and is the best medium resistance among all elastomers at present.

2. Excellent high temperature resistance, currently the best among elastomers.

3. Aging resistance, fluororubber has excellent weathering resistance and ozone resistance. 

4. Has excellent vacuum performance. 

5. Fluorine rubber has excellent physical and mechanical properties. 

6. Fluorine rubber has good electrical properties and can be used as a better electrical insulating material. 

7. Small air permeability and radiation resistance. 

Matters needing attention in fluororubber formulations 

1. Raw rubber Some raw rubbers have poor processing performance, mainly due to high Mooney viscosity, which affects the processing fluidity of the rubber compound accordingly. 

2. Vulcanizing agent Vulcanization is to produce a certain degree of cross-linking of fluororubber, so that it has good performance. Such as hydroquinone, bisphenol A, bisphenol AF, etc., and the corresponding accelerator APP is used to meet the high-level performance requirements. 

3. Acid absorber Acid scavengers are also known as stabilizers. Generally, MgO, CaO, ZnO, PbO, and dibasic lead phosphite are used, and the dosage is generally 5 to 10 parts. In short, it is necessary to choose a suitable acid absorbing agent to meet the actual performance requirements. 

4. Reinforcing filler Fluoroelastomer is a self-reinforcing rubber. The general dosage is between 10 and 30 parts. At present, the commonly used reinforcing fillers are generally thermal carbon black (N 990), spray carbon black, silica, calcium carbonate, barium sulfate, calcium oxide, carbon fiber, etc. 

5. Processing aids It is to improve the mixing process of fluororubber, prevent scorch, improve the fluidity and extrusion performance of the rubber, and prevent sticking to the roller and mold during processing without affecting the performance of the rubber. The role of external release agent. 

6. Skeleton bonding Plasticizing: The raw rubber is thinly passed 10 times in an open mill with a roll distance of 0.3~0.5mm, and the compounding agent can be added after wrapping the roll. 

Mixing: The capacity of fluororubber is smaller than that of synthetic rubber; 

Roller temperature: generally controlled at 40-60℃; Feeding sequence: raw rubber → acid absorber → processing aid → filler → vulcanization accelerator. After the compounding agent is added, evenly and thinly punch the triangle bag, roll it, and then release the sheet. 

The fluorine rubber vulcanization should be carried out twice: the first vulcanization is 165-170 ℃ × 10min; the second vulcanization is 230 ℃ × 24h (to ensure that the temperature is gradually heated, after reaching 230 ℃, the constant temperature is timed. 

Application of Fluorine Rubber 

1. Suitable for sealing materials used in chemical refining, oil mining, food processing, nuclear power and other equipment; 

2. Excellent durability for sodium hydroxide, ammonia water, oxidants (TMAN, NMP, etc.) practical in the liquid crystal semiconductor manufacturing line; 

3. It is suitable for the production of motor cables for high-speed railway vehicles. Its excellent electrical insulation, heat resistance and mechanical strength can meet the requirements of high current/thinning; 

4. Engine oils such as automobiles contain amine additives and high temperature engine oils also have excellent durability. 

5. It can be used as a sealing material for strategic missiles, launch vehicles, Shenzhou spacecraft and satellites. 

6. Suitable for highly corrosive chemical manufacturing, semiconductor chip manufacturing, pharmaceutical, oil and gas extraction, and aerospace applications. 

7. FDA-compliant seals can also be used in food, beverage and pharmaceutical production processes.