2.1.1 it is well known that the blending of different brands of fluororubber is easy to achieve in terms of compatibility or co vulcanization. If different brands of fluororubber (such as 2601 and 2605) are used together, the hardness and tensile strength of some fluororubber compounds can be reduced, and the elongation at break can be increased, so as to improve the processability of fluororubber. The fluorine content of fluororubber 2601 is 65%, Mooney viscosity is 90, and its processability is poor in production, while fluorine content of 2605 is 60%, Mooney viscosity is only 40. The results showed that the relative molecular weight distribution of fluororubber 2601 and 2605 was widened and the internal plasticizing effect was improved, which made the compound easier to extrude. The results show that the heat resistance of fluororubber 2601 will not be affected by the combination.
2.1.2 fluororubber / fluoroether rubber was synthesized in the early 1970s by using fluororubber / fluoroether rubber. The low temperature performance of fluororubber was significantly improved. For example, the glass transition temperature of VI tonglt raw rubber is 14 ℃ lower than that of f246, but its price is high. The fluororubber FX-13 was developed by Beijing Institute of aeronautical materials through the combination of fluororubber and fluoroether rubber. The low-temperature performance of fluororubber was improved. Its brittleness temperature was up to - 45 ℃. It has been successfully used in the manufacture of carrier rocket seals, and its price is much lower than that of fluoroether rubber. Basic formula (mass fraction): fluororubber 100, acid receptor 5-7; curing agent 2-2.8; carbon black 20-25. The optimum curing conditions were as follows: fluoroether rubber 100; acid acceptor 3-7; organic peroxide 3-5; CO curing agent 4-6; carbon black 20-25; blending ratio: 5:2; curing condition: 175 ± 3 ℃ / 10MPa × 20min.