China Suppliers EPDM, FKM, HNBR, NBR, and SI Rubber Products Factory - Material Selection Guide for Optimal Performance
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.
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℃. Resistant to polar solvents (e.g., alcohols, ketones, glycols, phosphate esters).
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℃. Oil resistance is similar to NBR, with better abrasion resistance, corrosion resistance, tensile/tear strength, and compression set. Resistant to ozone and sunlight. Suitable for detergent environments (e.g., laundry/dishwashing).
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 (except ketones/esters), weather, and ozone resistance. Poor low-temperature flexibility. Standard operating temperature: -20~250℃ (special grades down to -40℃).
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℃. Commonly used in oil seals and O-rings.
Silicone Rubber (SI)
With a silicon-oxygen backbone (-Si-O-Si-), SI features excellent heat, cold, ozone, and atmospheric aging resistance, plus high electrical insulation. However, it has low tensile strength and poor oil resistance. Modified formulations can achieve 1500 PSI tensile strength, 88 LBS tear resistance, and good elasticity/compression.
Fluorosilicone Rubber (FLS)
Fluorinated silicone rubber combines the benefits of fluoroelastomers and silicone rubber. It resists oils, solvents, fuels, and extreme temperatures (-55~250℃). Suitable for environments with oxygenated chemicals, aromatics, and chlorinated solvents. Avoid exposure to brake fluid, ketones, and hydrazine. Applications include aerospace components, semiconductors, chemical cleaning equipment, and medical/aviation seals.
PTFE (polytetrafluoroethylene)
PTFE (polytetrafluoroethylene) is a kind of polymer material. In its molecular structure, carbon atoms form stable covalent bonds with fluorine atoms, and it has a highly symmetrical linear structure. This structure endows it with excellent properties such as chemical stability, corrosion resistance and a low coefficient of friction.
Perfluoroelastomer (FFKM)
Offers maximum heat resistance, excellent chemical resistance, low outgassing, and plasma resistance.
Frequently Asked Questions
What is the difference between traditional sulfur-vulcanized EPDM and EPDM peroxide material?
EPDM peroxide material is cross-linked using a peroxide system, achieving a more uniform network. This results in higher tensile strength, lower compression set, and superior resistance to chloramine-containing drinking water and high-temperature steam compared to traditional sulfur-vulcanized EPDM.
What are the typical operating temperatures for HNBR and FKM?
HNBR typically operates within a temperature range of -40°C to 160°C. FKM (Fluorocarbon Rubber) has a standard operating range of -20°C to 250°C, with special low-temperature grades capable of reaching down to -40°C.
When should Fluorosilicone Rubber (FLS) be used instead of standard Silicone Rubber (SI)?
FLS combines the benefits of fluoroelastomers and silicone. FLS should be selected over standard SI when the application requires resistance to aggressive media like oils, solvents, fuels, oxygenated chemicals, and chlorinated solvents, while still maintaining flexibility at extreme temperatures (-55°C to 250°C).
What are the primary limitations of PTFE?
While PTFE exhibits outstanding chemical stability, corrosion resistance, and low friction, it is primarily used for rigid or semi-rigid applications such as coatings, anti-corrosion linings, and insulation rather than highly dynamic elastomeric sealing due to its plastic nature.
Why is Perfluoroelastomer (FFKM) considered a premium sealing material?
FFKM offers the maximum heat and chemical resistance among all elastomers, coupled with low outgassing and plasma resistance. This makes it ideal for highly critical environments like semiconductor processing and high-vacuum applications, despite its higher cost and manufacturing complexity.