Quick Answer
Chlorohydrin rubber (ECO/GECO) is a specialty elastomer positioned between NBR and FKM. Compared with NBR, it offers better fuel resistance, ozone resistance and lower permeability. Compared with FKM, it provides a more cost-effective solution for applications that require fuel and oil resistance but do not require extreme temperature performance. ECO/GECO is widely considered for automotive fuel systems, sealing components and advanced rubber applications.
Chlorohydrin Rubber vs NBR vs EPDM vs FKM: Complete Elastomer Selection Guide
How Engineers Choose the Right Rubber Material for Fuel, Oil, Heat and Environmental Resistance
Selecting the right elastomer is one of the most important decisions in rubber engineering.
A rubber material must not only provide sealing performance, but also withstand challenging environments including:
- Fuel exposure
- Oil and chemical contact
- High temperature
- Ozone and weather aging
- Compression set
- Dynamic fatigue
- Cost requirements
Common elastomers such as NBR, EPDM, FKM and chlorohydrin rubber (ECO/GECO) each have their own advantages.
However, no single rubber material can achieve the highest performance in every category.
The correct selection depends on the actual application requirements.
This guide compares:
- Chlorohydrin Rubber (ECO/GECO)
- NBR (Nitrile Rubber)
- EPDM (Ethylene Propylene Diene Rubber)
- FKM (Fluoroelastomer)
and explains when chlorohydrin rubber can become an effective alternative.
Quick Comparison: Elastomer Selection Guide
| Material | Fuel Resistance | Oil Resistance | Ozone Resistance | Temperature Range | Cost Level |
| NBR | ★★★ | ★★★ | ★ | -40°C ~ 120°C | Low |
| EPDM | ★ | ★★ | ★★★★★ | -50°C ~ 150°C | Low |
| FKM | ★★★★★ | ★★★★★ | ★★★★ | -20°C ~ 250°C | High |
| ECO / GECO Chlorohydrin Rubber | ★★★★ | ★★★★ | ★★★★ | -40°C ~ 150°C | Medium-High |
- NBR (Nitrile Rubber)
Balanced Oil Resistance at Competitive Cost
NBR is one of the most widely used industrial elastomers.
Its excellent resistance to:
- Mineral oils
- Hydraulic oils
- Lubricants
- Greases
makes it a common choice for:
- Oil seals
- Hydraulic seals
- Fuel hoses
- Gaskets
- Automotive rubber components
Advantages of NBR
✔ Good oil resistance
✔ Good mechanical strength
✔ Low material cost
✔ Easy processing
Limitations
However, NBR has several weaknesses:
- Poor ozone resistance
- Poor weather aging resistance
- Limited high-temperature performance
Long-term exposure to sunlight, ozone or harsh environments may cause cracking.
Typical Applications
- Hydraulic systems
- Oil-resistant seals
- General automotive components
- EPDM (Ethylene Propylene Diene Rubber)
Excellent Weather and Ozone Resistance
EPDM is known for outstanding environmental resistance.
It performs extremely well against:
- Ozone
- UV radiation
- Weather aging
- Steam
- Hot water
Typical applications include:
- Automotive cooling systems
- Door seals
- Window seals
- HVAC systems
- Water hoses
Advantages of EPDM
✔ Excellent ozone resistance
✔ Excellent aging resistance
✔ Good heat resistance
✔ Cost-effective
Main Limitation
EPDM has poor compatibility with:
- Gasoline
- Diesel fuel
- Petroleum oils
Therefore, EPDM is generally not selected for fuel-contact applications.
- FKM (Fluoroelastomer)
Premium Performance for Extreme Chemical Environments
FKM, commonly known as Viton®, represents one of the highest-performance elastomers.
It provides outstanding resistance to:
- Fuel
- Oil
- Solvents
- Chemicals
- High temperatures
Applications include:
- Aerospace sealing
- Automotive fuel systems
- High-temperature engine components
- Chemical processing equipment
Advantages of FKM
✔ Excellent fuel resistance
✔ Excellent oil resistance
✔ High-temperature capability
✔ Superior chemical resistance
Limitations
The disadvantages are mainly:
- High raw material cost
- Higher processing cost
- Limited low-temperature flexibility
For many applications, FKM performance is beyond the actual requirement.
- Chlorohydrin Rubber (ECO / GECO)
A Balanced Alternative Between NBR and FKM
Chlorohydrin rubber, including:
- ECO (Epichlorohydrin Homopolymer)
- GECO (Epichlorohydrin Copolymer)
is a specialty elastomer designed for applications requiring:
- Fuel resistance
- Oil resistance
- Low gas permeability
- Ozone resistance
- Good dynamic performance
It provides a performance balance between conventional NBR and premium FKM.
Why Choose Chlorohydrin Rubber?
- Excellent Fuel Resistance
Compared with NBR, chlorohydrin rubber provides improved resistance to:
- Gasoline
- Fuel vapor
- Automotive fluids
This makes it suitable for:
- Fuel hoses
- Fuel system seals
- Emission control components
- Lower Gas Permeability
One of the key advantages of ECO/GECO is its excellent barrier performance.
It shows lower permeability to:
- Fuel vapor
- Air
- Automotive gases
This property is especially important for:
- Fuel systems
- EV thermal management
- Sealing applications
- Better Ozone and Weather Resistance Than NBR
Unlike traditional NBR:
- ECO/GECO provides improved ozone resistance
- Better long-term outdoor durability
- Reduced surface cracking risk
- More Cost-Effective Than FKM
For applications requiring:
- Fuel resistance
- Chemical resistance
- Medium temperature performance
but without extreme FKM requirements,
chlorohydrin rubber can provide a better cost-performance balance.
Chlorohydrin Rubber vs NBR vs EPDM vs FKM: Application Selection
| Application | Recommended Material |
| General oil seals | NBR |
| Hydraulic systems | NBR |
| Outdoor weather seals | EPDM |
| Cooling water hoses | EPDM |
| Fuel hoses | ECO / GECO / FKM |
| Fuel vapor systems | ECO / GECO |
| High-temperature chemical sealing | FKM |
| Cost-sensitive fuel applications | ECO / GECO |
Automotive Applications of Chlorohydrin Rubber
Chlorohydrin rubber is widely considered for:
Fuel System Components
Including:
- Fuel hoses
- Fuel injection seals
- Fuel tank components
- Vapor recovery systems
Automotive Thermal Management
Especially for:
- Hybrid vehicles
- Electric vehicles
- Battery thermal systems
Requirements include:
- Coolant compatibility
- Low permeability
- Long service life
Dynamic Sealing Components
Because of its excellent resilience and fatigue resistance:
- Diaphragms
- Flexible connectors
- Vibration isolation parts
How to Select Between ECO/GECO and FKM?
| Requirement | Recommended Material |
| Maximum chemical resistance | FKM |
| Temperature above 200°C | FKM |
| Fuel resistance with controlled cost | ECO/GECO |
| Low permeability requirement | ECO/GECO |
| General oil resistance | NBR |
| Outdoor durability | EPDM |
Engineering Decision: Performance vs Cost
A simple way to understand elastomer selection:
| Material | Performance Level | Cost Level |
| NBR | Basic oil resistance | Low |
| EPDM | Environmental resistance | Low |
| ECO/GECO | Balanced fuel + oil + ozone resistance | Medium |
| FKM | Extreme chemical and temperature resistance | High |
For many automotive and industrial applications, ECO/GECO provides a balanced solution between NBR economy and FKM premium performance.
Why Choose YQXPOLYMER Chlorohydrin Rubber?
YQXPOLYMER provides specialty elastomer solutions focusing on:
- Chlorohydrin rubber (ECO/GECO)
- High-performance rubber materials
- Customized grades for sealing and automotive applications
Our materials are developed for applications requiring:
✔ Fuel resistance
✔ Oil resistance
✔ Low permeability
✔ Ozone resistance
✔ Reliable long-term sealing performance
Whether you are replacing NBR, optimizing cost compared with FKM, or developing new automotive rubber components, YQXPOLYMER can provide suitable elastomer solutions.
Frequently Asked Questions (FAQ)
Is chlorohydrin rubber better than NBR?
Chlorohydrin rubber generally provides better fuel resistance, ozone resistance and gas barrier performance than NBR, making it suitable for more demanding automotive applications.
Can chlorohydrin rubber replace FKM?
In medium-temperature applications where extreme chemical resistance is not required, ECO/GECO can be a cost-effective alternative to FKM.
What is the difference between ECO and GECO rubber?
ECO is epichlorohydrin homopolymer rubber, while GECO is an epichlorohydrin copolymer with improved low-temperature flexibility and processing characteristics.
Is EPDM suitable for fuel applications?
No. EPDM has excellent weather resistance but poor resistance to petroleum fuels and oils.
