In harsh industrial scenarios such as automotive, aerospace, and fluid piping, ordinary organic silicone rubber lacks sufficient resistance to fuel and solvents. Moreover, some fluorosilicone materials have difficulties in extrusion molding and are prone to collapse and deformation during extrusion. These have long been common industry challenges faced by rubber product manufacturing plants. The extrusion process poses dual tests on the fluidity, mouth expansion, and heat setting ability of the rubber compound. It must ensure smooth and continuous extrusion while also guaranteeing that the extruded material does not sag or deform, and at the same time, it needs to balance the core indicators such as oil resistance, high-temperature resistance, and compression permanent deformation.


IOTA F5760, as a 60 Shore A extrusion-specific fluorosilicone compound, is specifically optimized for extrusion processing, balancing processing performance with resistance to media and mechanical properties. It provides a domestic material solution for continuous extrusion fluorosilicone products.


The fluorosilicone compound (FVMQ) combines the dual advantages of organic silicone rubber's resistance to high and low temperatures and high elasticity with the oil resistance and solvent resistance of fluororubber, making it a high-end specialty elastomer. It is widely used in fuel piping, oil seals, special-shaped sealing strips, and solvent-resistant hoses, among others. Many fluorosilicone compounds on the market tend to be mold-based formulations, meeting mechanical performance standards but often experiencing unstable extrusion, soft collapse of the material, excessive mouth expansion, and large dimensional fluctuations, directly resulting in high production scrap rates and limiting the mass production efficiency of continuous extrusion lines. IOTA F5760 is specifically developed for the extrusion process, requiring no complex modification and adjustment. After adding a curing agent, it can undergo heat curing processing, suitable for mainstream extrusion production lines such as microwave continuous curing and hot air tunnel curing.


IOTA F5760 has a pale yellow semi-transparent appearance, with a density of 1.45 g/cm³ and a hardness of 60 Shore A. It is a common hardness grade for extruded fluorosilicone products. The core advantages of the product lie in its extrusion processing performance, mechanical strength, oil resistance, solvent resistance, and wide temperature range usage. First, the extrusion is smooth and the shaping effect is good, ensuring that the extruded material maintains its shape and is not prone to collapse or deformation, making it suitable for the production of complex cross-sectional special-shaped bars and hoses. Second, the comprehensive mechanical properties are balanced, with a tensile strength of up to 9 MPa, a tear elongation of 320%, a撕裂强度 of 20 KN/m， and an elastic recovery of 25%， meeting the requirements for sealing components to withstand tearing and repeated deformation. Third， the compression permanent deformation at 177°C for 22 hours is only 15%， ensuring low loss of sealing reliability during long-term high-temperature operation. Fourth， it has oil resistance， solvent resistance， and high-temperature resistance， with a volume change rate of + 20% after 25°C/72h immersion in Fuel C fuel， capable of enduring long-term erosion from fuel and lubricating oil， while inheriting the wide temperature range working ability of fluorosilicone materials.


Under the heat aging test conditions of 200°C for 72 hours， the hardness change is only + 3 Shore A， the tensile strength change is -20%， and the elongation change is -20%. The heat aging performance is stable. It is worth noting that if the product requires higher hardness indicators for heat resistance， a specific heat-resistant additive needs to be combined in the formula to achieve performance upgrades. All data in the table are typical reference values and are not used as factory judgment standards. Actual performance will be affected by curing processes， fillers， and additives.


## Standard Curing Process Reference


This compound uses an azo compound curing system and is recommended to add 2 parts of bis-dichlorosulfide.
First-stage curing： 120°C for 15 minutes to complete the molding cross-linking；
Second-stage curing： 200°C for 4 hours. 


The second-stage curing is an indispensable process for fluorosilicone compound extrusion. It is used to remove small molecules from the curing process， further stabilizing mechanical properties， compression permanent deformation， and media resistance. If the second-stage curing is omitted， the product will experience problems such as strong odor， poor compression permanent deformation， and decreased oil resistance. During actual production, the processing plant can adjust the sulfurizing agent type, addition quantity, temperature and time of the first and second stages of sulfurization based on the extrusion equipment, the wall thickness of the product, and the line speed. For overly thick products, the duration of the second-stage sulfurization should be appropriately extended.


## Main Application Areas


1. Automotive industry: Fuel-resistant special-shaped sealing strips, fuel system hoses, oil seals, pipe joint sealing parts, components exposed to gasoline, engine oil, and lubricating oil conditions;
2. Aerospace components: Extruded profiles resistant to aviation fuel, flexible connection rubber hoses, seals for high and low temperature alternating environments;
3. Chemical equipment: Extruded rubber strips, hoses, protective sheaths that come into contact with hydrocarbon solvents and oil materials;
4. Special equipment: Continuously extruded shaped elastic products that need to simultaneously meet oil resistance and high/low temperature resistance.


## Practical Processing Tips


1. Mixing operation: After the open mill machine completes the re-mixing and uniformity, add the double-dioxide sulfurizing agent, complete the feeding, thin out and evenly disperse to avoid local accumulation of sulfurizing agent causing bubbles and scorching in the product;
2. Sulfurizing agent selection: Besides the double-dioxide, other compatible peroxide sulfurizing agents can be selected based on the extrusion equipment and process conditions. The corresponding sulfurization temperature and time for different sulfurizing agents need to be re-verified;
3. Heat resistance improvement: If customers have higher long-term heat resistance requirements, it is necessary to provide heat-resistant additives. The heat resistance performance of the basic rubber compound is the benchmark level;
4. Storage conditions: The fluorosilicone mixed rubber needs to be stored in a cool and dark place to avoid premature cross-linking due to high temperature. After opening, use it as soon as possible. Mixing in impurities will directly affect the extrusion appearance and product properties;
5. Batch verification: Before production, it is recommended to conduct small-scale trial production to confirm the extrusion expansion rate, shaping effect, and sulfurization process, and then proceed with large-scale production.


## Common Questions in the Industry


Q: Can IOTA F5760 be directly molded into products?
A: The formula is focused on the extrusion process. Molded products can also be formed, but the moldability and demolding performance of molded products are not as good as the dedicated fluorosilicone mixed rubber for molding. It is preferred for extrusion strips, hoses, and continuous profiles.


Q: What does Fuel C volume change + 20% mean?
A: It represents a 20% volume expansion after being soaked in aviation fuel under standard test conditions. It falls within the normal range of 60-degree extruded fluorosilicone rubber. Different brands of fluorosilicone rubber have different fluorine content, and the volume change resistance to fuel will vary.


Q: Why are the extruded products prone to bubbles?
A: Common reasons: Inhomogeneous dispersion of the sulfurizing agent; insufficient cross-linking in the first-stage sulfurization; insufficient execution of the second-stage sulfurization; air bubbles are trapped inside the extruded billet. These issues need to be investigated one by one through thinning and dispersion in the mixing process, addition of the sulfurizing agent, and sulfurization temperature and time.


With the promotion of domestic high-end manufacturing localization, the demand for extruded fluorosilicone materials continues to rise. To solve the pain points of long lead times and high costs of imported materials, domestic fluorosilicone mixed rubber is rapidly replacing the market share of imported products. IOTA F5760 focuses on extrusion processing scenarios, addressing the pain point of difficult extrusion and molding of traditional fluorosilicone rubber, reducing the difficulty of process debugging while ensuring the core performance of oil resistance and temperature resistance, and adapting to the vast majority of domestic extrusion and sulfurization production lines. In the material selection stage, enterprises need to conduct small-scale sample tests to confirm the final process parameters based on the actual medium types, temperature ranges, and cross-sectional dimensions of the products, to ensure the stability of batch production.