China Rubber Products Material Selection Guide: EPDM, FKM, HNBR, NBR, and More from Reliable Suppliers and Factory
EPDM Peroxide
EPDM peroxide material is a cross - linked elastomer formed by introducing a small amount of third monomers with double bonds (such as ENB) into the main chain of ethylene - propylene copolymer and through the peroxide vulcanization system. Its saturated main chain structure endows it with excellent heat resistance (from - 55°C to 150°C), weather resistance, ozone resistance and chemical stability, especially showing outstanding performance in complex media such as chloramine - containing drinking water and ethylene glycol coolant.
Compared with traditional sulfur - vulcanized EPDM, the EPDM peroxide material achieves higher tensile strength, lower compression set and chloramine - resistant performance that complies with the standards of many countries through a uniform cross - linked network. Its advantages such as resistance to chemical media erosion, high - temperature steam resistance (with a short - term peak of 180°C) and gas impermeability make it widely used in industrial steam pipeline sealing, pipeline sealing for medical gases, solar energy, oil and natural gas, high - end bathrooms, new energy vehicle battery cooling systems and automotive turbocharger components, etc., providing long - term sealing solutions for harsh environments.
- Global Certifications: Passed AS NZS4020 (Australia/New Zealand), JFSL 370/JIS S3200 - 7 (Japan), KIWA (Netherlands), KTW - BWGL/UBA - LL/W270/W534/DVGW (Germany), NSF61 (USA), Ö - NORM/LMG (Austria), WRAS/WRC (UK), EN681 - 1 (Europe), PAH (Polycyclic Aromatic Hydrocarbons) related certifications, and ACS (France).
Ethylene Propylene Diene Monomer (EPDM)
A copolymer of ethylene and propylene with a saturated backbone, EPDM exhibits excellent heat, aging, ozone, and chemical stability but cannot be sulfur-vulcanized. Sulfur vulcanization becomes possible with a third monomer containing double bonds (EPDM).
- Operating Temperature: -45~100℃.
- Chemical Resistance: Resistant to polar solvents (e.g., alcohols, ketones, glycols, phosphate esters).
- Key Advantages: Weather, ozone, and water resistance; high-temperature steam tolerance; good gas impermeability.
- Disadvantages: Unsuitable for food contact or aromatic hydrocarbon exposure.
- Typical Applications: High-temperature steam seals, bathroom installations, braking systems, and radiator gaskets.
Hydrogenated Nitrile Rubber (HNBR)
Produced by hydrogenating nitrile rubber to reduce double bonds, HNBR offers superior heat and weather resistance compared to NBR.
- Operating Temperature: -40~160℃.
- Performance Strengths: Oil resistance is similar to NBR, with better abrasion resistance, corrosion resistance, tensile/tear strength, and compression set. Excellent resistance to ozone and sunlight. Suitable for detergent environments (e.g., laundry/dishwashing).
- Disadvantages: Incompatible with alcohols, esters, or aromatic solutions.
- Typical Applications: R134a refrigerant seals and automotive engine systems.
Fluorocarbon Rubber (FKM)
FKM contains fluorine in its polymer structure, with types defined by fluorine content. The 6-fluorinated variety (e.g., DuPont’s "Viton") offers superior heat resistance over silicone rubber, along with excellent chemical, oil, weather, and ozone resistance.
- Operating Temperature: -20~250℃ (special grades down to -40℃).
- Resistances: Resists most oils, solvents, acids, aliphatic/aromatic hydrocarbons, and animal/vegetable oils. Poor low-temperature flexibility.
- Disadvantages: Incompatible with ketones, low-molecular-weight esters, and nitrate mixtures.
- Typical Applications: Automotive fuel systems, diesel engines, and chemical plant seals.
Nitrile Rubber (NBR)
A copolymer of acrylonitrile and butadiene (acrylonitrile content: 18%~50%). Higher acrylonitrile content improves resistance to petroleum oils and hydrocarbons but reduces low-temperature flexibility.
- Operating Temperature: -50~100℃.
- Key Advantages: Outstanding oil, water, and solvent resistance; good compression set, abrasion resistance, and elongation.
- Disadvantages: Incompatible with polar solvents (e.g., ketones, ozone, nitrohydrocarbons, MEK, chloroform).
- Typical Applications: Oil seals, O-rings, fuel/lubricant tanks, and rubber parts exposed to petroleum-based hydraulic oils, gasoline, water, silicone grease, esters, and glycols.
Silicone Rubber (SI)
Featuring a silicon-oxygen backbone (-Si-O-Si-), SI exhibits excellent heat, cold, ozone, and atmospheric aging resistance, alongside high electrical insulation. While standard formulations have low tensile strength and poor oil resistance, modified grades can achieve 1500 PSI tensile strength, 88 LBS tear resistance, and outstanding elasticity/compression.
- Resistances: Highly resistant to neutral solvents, thermal extremes, ozone, and oxidation.
- Disadvantages: Incompatible with concentrated solvents, oils, acids, and diluted NaOH.
- Typical Applications: Household appliances (kettles, irons, microwaves), electronics (phone keys, DVD pads), and human-contact products (water dispensers).
Fluorosilicone Rubber (FLS)
Fluorinated silicone rubber (FVMQ) combines the physical properties of silicone rubber with the chemical and oil resistance of fluoroelastomers.
- Operating Temperature: -55~250℃.
- Resistances: Resists oils, solvents, fuels, oxygenated chemicals, aromatics, and chlorinated solvents.
- Disadvantages: Avoid exposure to brake fluid, ketones, and hydrazine.
- Typical Applications: Aerospace components, semiconductors, chemical cleaning equipment, and medical/aviation seals.
PTFE (polytetrafluoroethylene)
PTFE (polytetrafluoroethylene) is a polymer material featuring a highly symmetrical linear structure where carbon atoms form stable covalent bonds with fluorine atoms. This structure endows it with excellent properties such as chemical stability, corrosion resistance, and an extremely low coefficient of friction.
- Key Applications: Anti-corrosion equipment for construction machinery, oil cylinders, chemical pipelines, and reaction kettles.
- Surface Coatings: Used as a non-stick coating for cookware to prevent food adhesion, and sprayed onto rubber sealing rings to facilitate automatic assembly.
- Electrical Properties: Serves as an insulating material in wires and cables to improve electrical performance and weather resistance.
Perfluoroelastomer (FFKM)
FFKM represents the highest class of chemical and thermal resistance among elastomers, offering low outgassing and high plasma resistance.
- Key Advantages: Maximum heat resistance, outstanding chemical resistance, minimal outgassing, and excellent plasma resistance.
- Disadvantages: Poor low-temperature flexibility, high material cost, and complex manufacturing requirements.
- Typical Applications: Semiconductor manufacturing, thin-film processes (PVC, CVD, etching), and high-vacuum seals.
Frequently Asked Questions (FAQ)
Q1: What makes EPDM Peroxide superior to traditional sulfur-vulcanized EPDM?
EPDM Peroxide features a uniform cross-linked network, allowing it to achieve higher tensile strength, lower compression set, and superior resistance to chloramine-containing drinking water compared to sulfur-vulcanized EPDM.
Q2: What is the operating temperature range of HNBR?
Hydrogenated Nitrile Rubber (HNBR) operates effectively in temperatures ranging from -40°C to 160°C, offering superior heat and weather resistance compared to standard NBR.
Q3: In what environments should Fluorocarbon Rubber (FKM) be avoided?
FKM is incompatible with ketones, low-molecular-weight esters, and nitrate mixtures. It also exhibits poor low-temperature flexibility.
Q4: Why is Nitrile Rubber (NBR) commonly used in O-rings and oil seals?
NBR is highly favored for O-rings and oil seals due to its exceptional resistance to petroleum-based oils, water, and solvents, alongside its good compression set and abrasion resistance.
Q5: What are the key applications and benefits of PTFE?
PTFE offers excellent chemical stability, corrosion resistance, and a low coefficient of friction. It is widely used in anti-corrosion equipment, non-stick pan coatings, and wire insulation.
Q6: When is FFKM preferred over other elastomers?
Perfluoroelastomer (FFKM) is preferred in high-temperature, aggressive chemical, or plasma environments, such as semiconductor manufacturing, thin-film processes, and high-vacuum sealing, where maximum thermal and chemical stability is required.