Basic Material Properties
Fluorosilicone rubber (FVMQ) is a specially modified silicone rubber with trifluoropropyl (-CF2CF2CH3) groups introduced into its molecular structure. This structure gives it both the oil and solvent resistance of fluororubber and the temperature resistance of silicone rubber. Its applicable temperature range is -68℃ to 232℃ (short-term temperature resistance up to 250℃), and its low-temperature brittleness can reach -89℃.

Phenylacetic silicone rubber, on the other hand, is a modified silicone rubber with phenyl and vinyl groups introduced into the siloxane backbone. Its main advantages are high and low temperature resistance (-70℃-350℃) and radiation resistance, but its oil resistance is relatively poor.

Comparison of Fuel Resistance Performance
Performance Indicators: Fluorosilicone Rubber, Phenylvinyl Silicone Rubber
Fuel Resistance: Excellent (resistant to fuel oil, engine oil, aromatic hydrocarbons, etc.) Poor
Applicable Temperature: -68℃~232℃ (short-term 250℃) -70℃-350℃
Volume Change: Small volume change after immersion in fuel oil; Easily swells in fuel oil
Mechanical Property Retention: High mechanical property retention rate after immersion in high-temperature fuel oil (>70%); Significant decrease in mechanical properties

Long-term Stability: Maintains elasticity for a long time in fuel oil; Unstable performance with long-term use
Fluorosilicone rubber exhibits significantly better fuel resistance than phenylvinyl silicone rubber, mainly due to the trifluoropropyl groups in its molecular structure, which effectively resist the swelling effect of fuel oil. Under fuel oil immersion conditions, fluorosilicone rubber can reach a maximum service temperature of 180℃ while maintaining good elasticity.

Comparison of Aviation Kerosene Resistance
Performance Indicators: Fluorosilicone Rubber, Phenylvinyl Silicone Rubber
Aerospace Kerosene Resistance: Excellent (Meets stringent requirements of aviation fuel systems) Poor
Expansion Rate: <10% (Long-term immersion at 150℃) No specific data
Mechanical Property Retention: >70% (After high-temperature fuel immersion) No specific data
Applicable Standards: Meets aviation fuel standards such as Jet A and JP-8; Does not meet aviation fuel standards
Application Cases: Aircraft fuel tank seals, fuel line seals; Aerospace non-fuel contact components

Fluorosilicone rubber is one of the few elastomer materials that can pass the stringent evaluation of aviation fuel systems. Its vulcanized rubber exhibits very small volume change (expansion rate <10%) after long-term immersion in aviation kerosene (such as Jet A and JP-8) at high temperatures (150℃), while maintaining sufficiently high retention rates of mechanical properties such as tensile strength and elongation at break (>70%). In contrast, the application of phenylvinyl silicone rubber in the aviation field is more based on its temperature resistance and radiation resistance than its oil resistance.

Application Area Differences
Fluorosilicone Rubber Applications:
Aerospace fuel system seals (fuel tank seals, fuel line seals)
Automotive fuel system seals
Petrochemical equipment seals
Special fuel contact components

Phenylene vinyl silicone rubber Applications:
Aerospace non-fuel contact components
Electronic and electrical seals
Medical devices
Conventional industrial seals

Fluorosilicone Rubber: Fuel resistance can be further improved by optimizing the trifluoropropyl content and vulcanization system, while maintaining good low-temperature performance.

Phenylene vinyl silicone rubber: Fuel resistance can be improved by adding specific oil-resistant modifiers, but the effect is limited.
Composite Material Development: Studies show that blending fluorosilicone rubber with phenyl vinyl silicone rubber can balance oil resistance and other mechanical properties.

Conclusion: In terms of fuel oil and aviation kerosene resistance, fluorosilicone rubber is significantly superior to phenyl vinyl silicone rubber, mainly due to the trifluoropropyl groups in its molecular structure effectively resisting the swelling effect of fuel. For applications involving contact with fuel oil and aviation kerosene, fluorosilicone rubber is the only suitable choice; while for applications not involving contact with fuel oil but requiring resistance to high and low temperatures or radiation, phenyl vinyl silicone rubber may be more suitable. Material selection should comprehensively consider the type of medium, temperature requirements, and other performance requirements of the specific application scenario.