In the world of industrial sealing and fluid control, rubber valves play a crucial role in regulating gases and liquids under specific pressure and vacuum conditions. As a professional rubber valve manufacturer, Neosilicone has decades of experience in designing, engineering, and producing customized rubber valve solutions for industries ranging from medical devices and household appliances to petrochemicals and aerospace.
When our customers approach us, they often want to know: What are the differences between silicone, fluorosilicone, and nitrile rubber (NBR) valves? Which one should I choose for my application?
In this blog, we’ll take a deep dive into the material science, performance characteristics, and application scope of these three valve types. Our goal is to give you the knowledge needed to make the right choice — and to show how Neosilicone’s one-stop service and custom service capabilities can help you get the exact solution tailored for your needs.
1. Material Foundations
Silicone Valves
Silicone valves are primarily made of silicone rubber, a material known for its excellent thermal stability and flexibility. Silicone rubber is based on a siloxane polymer backbone (Si–O–Si), with organic groups such as methyl or phenyl attached to the chains. This unique structure allows silicone valves to maintain elasticity and sealing performance even at extreme temperatures.
For industries that prioritize safety, hygiene, and non-toxicity — such as food & beverage or pharmaceuticals — silicone valves are often the first choice. They comply with FDA and medical-grade standards, making them reliable for critical fluid handling.
Fluorosilicone Valves
Fluorosilicone rubber builds on the silicone base but incorporates fluorine atoms into its side chains. This subtle yet powerful modification dramatically improves chemical stability, especially against fuels, oils, and aggressive solvents. The result is a material that not only withstands extreme heat but also resists corrosion in chemically harsh environments.
Structurally, fluorosilicone combines the Si–O–Si backbone with trifluoropropyl side groups, enhancing durability without sacrificing flexibility. These valves are often specified in aerospace, defense, and petrochemical industries where ordinary silicone may fail.
NBR (Nitrile Rubber) Valves
NBR valves are made from nitrile rubber, a copolymer of acrylonitrile and butadiene. Unlike silicone-based rubbers, NBR is inherently oil-resistant, making it an ideal material for handling fuels, lubricants, and other hydrocarbon-based media.
Its composition gives it exceptional resistance to wear and tear, mechanical stress, and certain solvents. While its heat resistance is not as high as silicone or fluorosilicone, NBR is often the most cost-effective choice for industrial applications requiring durability and oil compatibility.
2. Performance Characteristics
Temperature Resistance
- Silicone Valves: Reliable from –50°C to 200°C, maintaining elasticity and flexibility.
- Fluorosilicone Valves: Wider range, –50°C to 250°C (or higher), making them ideal for aerospace and petrochemical sectors.
- NBR Valves: Typically stable within –30°C to 120°C, slightly more limited but sufficient for most oil and fuel systems.
Chemical Resistance
- Silicone: Performs well with water-based media and mild chemicals but struggles with oils and fuels.
- Fluorosilicone: Excellent resistance to strong acids, alkalis, fuels, and solvents.
- NBR: Exceptional resistance to oils, greases, and petroleum-based products, widely used in automotive and petrochemicals.
Mechanical Properties
- Silicone: High elasticity and flexibility but may experience permanent deformation under sustained stress.
- Fluorosilicone: Comparable elasticity but with better tensile and tear strength, ensuring longer lifespan in demanding conditions.
- NBR: Harder and more wear-resistant, with strong tear resistance, suitable for abrasive and high-friction environments.
Electrical Insulation
- Silicone: Outstanding electrical insulation, making it a top choice for electronics and medical devices.
- Fluorosilicone: Good insulation properties, though often chosen more for chemical resistance.
- NBR: Limited electrical insulation compared to silicone-based materials.
Weather & Aging Resistance
- Silicone: Excellent resistance to UV, ozone, and extreme climates.
- Fluorosilicone: Superior to silicone in harsh outdoor environments, maintaining integrity under prolonged exposure.
- NBR: Good resistance but more prone to aging and cracking under UV compared to silicone and fluorosilicone.
3. Application Scenarios
Silicone Valves
Used extensively in:
- Food and beverage packaging (drip-free bottle valves, dispensing systems)
- Medical & pharmaceutical devices (IV sets, respiratory equipment)
- Household appliances (coffee machines, water dispensers, steam cleaners)
Silicone valves are valued for their hygienic, flexible, and high-temperature-safe properties.
Fluorosilicone Valves
Engineered for high-performance and extreme conditions, they are found in:
- Aerospace: Fuel system seals, engine gaskets, vibration-damping valves
- Petrochemical plants: High-pressure sealing in corrosive chemical pipelines
- Industrial machinery: Acid- and solvent-resistant seals in pumps and valves
If you need a valve that resists both heat and aggressive chemicals, fluorosilicone is unmatched.
NBR Valves
Best suited for:
- Automotive industry: Fuel system components, gaskets, and seals
- Petrochemical applications: Oil and solvent delivery systems
- General industry: Valves exposed to lubricants, hydraulic fluids, and greases
NBR valves are often chosen for their balance of performance and cost-efficiency.
4. Choosing the Right Valve
When selecting between silicone, fluorosilicone, and NBR valves, the key factors include:
- Operating temperature range
- Type of media (water, oil, chemical solvents, etc.)
- Mechanical stress and wear
- Electrical insulation needs
- Cost considerations
At Neosilicone, we don’t just provide off-the-shelf products — we offer custom service and one-stop service to help you design, prototype, and mass-produce the most suitable valve for your unique application. Our engineers work closely with clients to match the right material to the right environment, ensuring performance, reliability, and cost-effectiveness.
Why Work With Neosilicone?
As a professional rubber valve manufacturer and factory, Neosilicone has the advantage of complete vertical integration. From tooling and mold design to raw material selection, precision molding, and quality testing, we control every step of the production process. This allows us to provide:
- One-stop service: From concept to finished product.
- Custom service: Tailored valve geometries, slit designs, hardness, and color matching.
- Strict quality assurance: ISO-certified processes to ensure consistent performance.
- Competitive factory pricing: Direct supply from the manufacturer with no middlemen.
Conclusion
Choosing between silicone, fluorosilicone, and NBR valves is not just a matter of preference — it’s about aligning the material properties with the functional requirements of your application. Whether your priority is food safety, chemical resistance, or oil compatibility, each material brings unique strengths to the table.
At Neosilicone, we’re more than just a supplier — we’re your manufacturing partner. With our custom service and one-stop service, we help global customers bring their projects from design to production with efficiency and precision.
If you’re exploring the best solution for your fluid control systems, we welcome you to visit our factory or contact us directly. Our engineering team is ready to provide expert guidance and tailor-made solutions that deliver long-term performance.