EPDM and silicone are the most popular synthetic rubber materials you will find in the market. If you are keen on a comprehensive comparison of EPDM vs. Silicone to make an informed choice for your applications, this post is for you.
While both EPDM and silicone have some similarities, do not be misled that you can easily replace one for the other. They have their differences. Each has its special properties and characteristics suitable for specific applications and conditions.
Some of the industries using these synthetic rubber include automotive, roofing, and electronics among other industrial applications.
In this article, we provide you with a detailed comparison between EPDM and Silicone materials in terms of their chemical compositions, characteristics and properties, advantages, disadvantages, and application areas where each is most desirable.
Finally, we explain some of the key factors you should consider before choosing either EPDM or Silicone for your various project requirements.
Let’s begin this enlightening revelation!
EPDM vs. Silicone Rubber Solutions- Brief Overview
EPDM Rubber Material
EPDM is an acronym that stands for Ethylene Propylene Diene Monomer. So, the chemical compositions of EPDM rubber are ethylene, propylene, and diene Monomers.
The history of EPDM synthetic rubber and its use in automotive and other industrial applications dates back to the 1950s.
Compared to silicone, EPDM is less costly. However, it is more durable and more resistant to ultraviolet light and ozone. It is, therefore, a perfect synthetic rubber material for your outdoor installations.
Depending on your application needs, EPDM comes in different forms such as EPDM rubber sheet, EPDM coating, EPDM o ring, and EPDM gasket materials among others.
Silicone Rubber Material
Silicone, like EPDM, is a synthetic rubber. Silicone is manufactured from polysiloxane with silicon(Si) and oxygen(O) as its main ingredients.
Silicone has remained popular in industrial applications since the 1940s. Compared to silicone, EPDM offers more resistance to extreme temperatures and boasts superior flexibility.
However, compared to EPDM, the manufacturing process of silicone is more complicated, and this makes it costly. Compared to EPDM, silicone is low in strength and less durable
EPDM vs. Silicone – Key Properties and Characteristics
So that you have a better understanding of these two rubber materials, let’s explore some of their key features that are critical in your EPDM vs. silicone material evaluation.
Characteristics & Properties of EPDM
Some of the properties and characteristics that EDPM as a synthetic rubber boasts of and place it in a unique position include:
- Weather Resistance: Highly resistant to external weather conditions such as UV light and ozone
- Chemical Resistance: EPDM material is resistant to chemicals such as alkalis, acids, and other solvents.
- Forms & Color Variations: EPDM comes in different forms with different hardness and color to suit application preferences
- Operation Temperature Range: Remains stable at temperatures of -40°F to 300°F.
- Hot Water Resistance: Provides good resistance to hot water or steam
- Low-Temperature Stability: Remains flexible even at low temperatures.
- Insulation Capability: EPDM offers good electrical and thermal resistance or insulation
Characteristics & Properties of Silicone
- High-Temperature Resistance: Compared to EPDM, Silicone is more resistant to extreme temperatures
- Flexible at Low Temperatures: Just like EPDM rubber, silicone material will also retain its flexibility even at low temperatures
- Good Resistance to Chemicals: While EPDM is a clear winner in this contest, silicone also offers excellent resistance to a wide range of chemicals and water.
- Many Selection Options: Compared to EPDM, silicone has more options when it comes to forms, hardness, or colors to choose from.
- Thermal and Electrical Insulation: Silicone as with EPDM offers good electrical and thermal insulation
- It’s Resistant to Water: It offers excellent resistance to water though not as much as EPDM.
EPDM vs. Silicone – Advantages and Disadvantages
Advantages of EPDM Compared to Silicone
The stable structure of EPDM makes it suitable for a wide range of applications.
Below are some of the advantages you get by choosing EDPDM over silicone:
High Temperature and Weather Resistance
EPDM rubber offers you more resistance to high temperatures in the range of -40°F to 300°F or 266°F for some grades. EPDM also withstands extreme weather conditions including ozone and UV rays.
Therefore, if you are keen on an external rubber material that is durable and resistant to extreme outdoor heat, oxidation, and aging, EPDM is your perfect choice.
Less Expensive
The manufacturing process of EPDM is less costly compared to silicone. So, in terms of material cost, it is less expensive.
More Water Resistant
In areas where water resistance is critical, EPDM rubber is a top performer compared to silicone. So, when your project deals with water storage or delivery systems, EPDM seals or gaskets will not let you down.
Highly Resistant to Chemicals
Another benefit of choosing EPDM rubber material is its excellent resistance to a wide range of chemicals and solvents.
When your processing industry involves the use of different chemicals including alkalis and acids, then choosing a suitable EPDM rubber material is a wise decision.
Superior Strength & Flexibility
EPDM rubber also beats silicone in terms of strength, flexibility, and resistance to abrasion.
These, therefore, make it a perfect choice for a wide range of industrial applications in areas where such properties are critical.
Non-Toxic & Environment-friendly
EPDM is FDA-approved as non-toxic and environment-friendly. Therefore, its composition is free from harmful organic chemicals.
Versatile In Its Applications
EPDM is a versatile rubber material that will address a wide range of your industry application requirements.
For instance, you will find EPDM rubber seals or gaskets, EPDM tubing solutions, and EPDM insulation rubber among other application forms.
Disadvantages of EPDM Compared to Silicone
Here are some of the limitations of EPDM material that you ought to be aware of.
Unstable at High Temperatures
When your application environment is exposed to high temperatures, EPDM is not your ideal rubber material.
This is because as the temperature moves above 300° F, EPDM material undergoes degradation pretty fast. It finally loses its flexibility and becomes brittle.
Flexibility Limitation
EPDM is not as stretchable as silicone. Therefore, it is less flexible. Because of this, you can only opt for it in areas where flexibility is not an important application factor.
Food Safe Limitations
Though Peroxide-cured EPDM may be used in non-conductive drinking water systems, it is not suitable for holding food materials. This is because it has no food-safe certification.
There are food-safe EPDM materials that are FDA-approved, but they are not as common as food-safe silicone.
EPDM rubber materials are generally not food-safe.
Therefore, where food handling is your concern, getting a food-safe silicone material will be much easier.
Less Resistance to Automative Brake Fluids
Compared to Silicone, EPDM rubber material performs poorly when it comes to automotive brake fluid resistance.
Advantages of Silicone Compared to EPDM
When you decide to go for a silicone material option for your different application requirements, here are some of the benefits you should expect:
Superior Tear and Abrasion Resistance
If your application requires a durable rubber material with high tear and abrasion resistance then Silicone is your winning choice.
More Tolerant to Extreme Hot Temperatures
Silicone provides you with a stable performance at temperatures as high as 350 degrees Fahrenheit (177°C) for certain high-performance grades.
This is above the EPDM’s range of about 250 degrees Fahrenheit (121 degrees Celcius) for some EPDM rubbers.
Special silicone grades with additives can be tolerant to extreme temperatures of up to 500 degrees Fahrenheit!
Therefore, for high-temperature application areas, silicone is your undisputed heat champion!
Superior Flexibility
Did you know that some grades of silicone can be safely elongated by 800%? Yes, silicone is more flexible or has a higher elongation compared to EPDM.
It is, therefore the most ideal rubber material you need in areas where flexibility is a major concern.
Better Compression Set
After undergoing compression, silicone rubber regains its original shape and size much better than EPDM.
Therefore, its excellent compression set ensures that its rubber seals, gaskets, or insulation material performs better in areas with high compression strain.
Food-Safe Application
Unlike peroxide-cured EPDM, Silicone is considered food-safe. Therefore, you can safely use a suitable silicone form such as tubes or rubber sheets in your food processing industry.
Resistant to Ozone and UVL
Just like EPDM rubber, Silicone is also resistant to ozone and UV light. Because it is not much affected by external weather conditions, you should not be worried about its use outdoors.
Chemical Resistance
Silicone has good resistance to chemicals including resistance to automotive brake fluids. This makes it your suitable synthetic rubber, especially in areas where contact with different chemicals is unavoidable.
Disadvantages of Silicone Compared to EPDM
Apart from its various advantages, here are some of the drawbacks of choosing silicone rubber
High Cost | Less Cost-effective
Compared to EPDM rubber, you will have to spend more on silicone. This is directly linked to its manufacturing cost. It is, therefore, less cost-effective if you are working on a tight budget.
Poor Tensile Strength
Another key limitation is silicone’s lower tensile strength. When subjected to pressure or excessive strain, it is more likely to tear or get deformed.
Therefore, where your application requires a high-tensile strength rubber material, EPDM rubber will serve you far better than silicone.
Lower Abrasion Resistance
The Abrasion resistance of Silicone is not as excellent as that of EPDM rubber. Therefore, in application areas where movements or frictions are expected, EPDM rubber would be your better choice.
However, it is important to note that there are grades of silicone with improved resistance to tear. A good example is silicone vacuum sheets.
Important Note 1: Apart from the above limitations, there are additional areas where silicone may have limitations compared to EPDM.
Important Note 2. Where either EPDM or silicone rubber has limitations, you need to consider all other critical factors. It is after assessing all the advantages and drawbacks that you ought to make a choice.
EPDM vs. Silicone Rubber – Comparison Table
| Comparison Features | EPDM | Silicone |
|---|---|---|
| Type of Rubber | Synthetic | Synthetic |
| Resistance to Environmental Elements such as UV and Ozone | Excellent resistance | Excellent resistance when enhanced |
| Oil Resistance | Not resistant to long exposure. Low resistance | Not resistant to long exposure but offers a better resistance |
| Abrasion Resistance | Good resistance to abrasion | Poor abrasion resistance |
| Chemical Composition | ethylene, propylene, and diene | Silicone and oxygen |
| Elongation | Can be Stretched | More Stretchable up to 80% |
| Ability To Resist Chemicals | Excellent Resistance | Good Resistance |
| Brittle Point Temperature | -40 degrees Celcius(-40 degrees Fahrenheit) | -60 degrees Celcius(-76 degrees Fahrenheit). Note: This can vary depending on different grades |
| Degradation Temperature, Maximum Temperature | 130 degrees Celcius(266 degrees Fahrenheit). Note: This can vary depending on different grades | 230 degrees Celcius(447 degrees Fahrenheit). Note: This can vary depending on different grades or enhancements. |
| Compression Set | Good Compression set | Superior Compression Set |
| Tensile Strength | Excellent Tensile Strength (14 MegaPascal) | Low Tensile Strength ( about 5 Mega Pascal. Can be enhanced for excellent performance |
| Electrical and Thermal Insulation | Excellent | Excellent |
| Water Resistance | Excellent Resistance | Good Resistance |
| Installation Ease | Easy but not as Silicone | Easy and Convenient |
EPDM vs. Silicone Rubber – Industry Uses and Applications
The unique properties of EPDM and silicone rubber make their application areas different.
However, it is important to note that while EPDM rubber has special application areas, silicone, on the other hand, has general applications.
Let’s look a closer look at their various application areas.
Application of EPDM Rubber
Some of the areas where EPDM rubber is applied include:
The Automotive Industry
If you are in the automotive industry, you will find different forms of EPDM rubber for a wide range of applications. The items include EPDM O-rings, gaskets, and seals.
Some of the EPDM application areas are in vehicle door seals, radiator hoses, window seals, and fuel lines among others.
Heat, Ventilation, and Aircondition Applications (HVAC)
EPDM rubber materials are used in HVAC to provide effective sealing. Its thermal resistance, insulation, and resistance to environmental conditions make it an excellent material for HVAC components
Building and Construction Industry
Within the construction industry, you will find ribbed-style EPDM rubber seals used in windows and doors to keep buildings free from dust or other environmental elements such as water or dust.
Their application in this sector is popular due to their excellent resistance to extreme weather conditions. This, therefore, makes them highly durable.
Sealing of Waterproof Sheets – Roofing Sector
Because EPDM rubber materials provide excellent resistance to water and UV, EPDM is a favorite for waterproofing applications.
EPDM rubber membrane, for instance, is commonly used in low-sloping roofs.
You can also order EPDM to seal a wide range of roofing materials or roof vents to eliminate water risks
Electrictronic Insulations
EPDM rubber just like silicone has good thermal and electrical insulation properties. Therefore, it is used in making electrical gaskets. You also find them used in electrical control systems and panel boards.
Seals and Gaskets Industry
Because EPDM provides excellent chemical resistance with desirable high-temperature tolerance, it provides a perfect solution if you are looking for seals and gaskets for use in medical, automotive, and general industry applications
Hoses and Tubing
Further, EPDM material is used in the manufacture of heat and chemical-resistant hoses and tubing, especially for the automotive industry.
EPDM hoses and tubing are mostly used in heating and cooling systems because of their excellent temperature resistance properties.
Masking Tasks
Because EPDM has excellent resistance to chemicals and solvents, it is used to seal or mask surfaces, especially during painting.
Silicone Material Application Areas
The properties and characteristics of silicone make it a useful rubber material in the following areas:
Medical Industry
Silicone rubber is non-toxic, biocompatible, and flexible making it a perfect manufacturing material in the medical manufacturing sector.
For instance, silicone is used in producing medical implants, prostheses, tubes, and a wide range of medical devices.
Other examples of silicon rubber items suitable for your medical facility include syringes, surgical masks, and medical equipment just to mention but a few.
Sealants Industry
If you go to purchase a general sealant in most hardware stores, you will never miss silicone sealants for different applications.
The use of silicone sealants ranges from sealing joints, and enclosures, and general waterproofing of tubes or pipes.
Industrial Applications
Thanks to its superior resistance to extreme temperatures among other properties, silicone is widely used to produce different silicone rubber items for industrial applications.
There is a wide range of sealing solutions for different applications.
Some of the common silicone products you can easily source from a reputable supplier include silicone door strip seals, gaskets, and silicone hose or tubing.
In the electronics industry, it is also used for insulation purposes in circuit boards.
Again, silicone is used to produce flame-retardant sheets for enhanced fire safety in industrial settings.
You will also come across various silicone adhesives and coatings to suit various requirements such as roof surface restoration.
Domestic Appliances Application
You can use a suitable EPDM rubber material to limit vibrations in your home appliances such as washing machines, or any other vibrating machines such as heavy-duty generators.
Choosing EPDM vs. Silicone Rubber – Factors You Must Consider
Now that you have a better understanding of both EPDM and silicone, how do you go about making the most suitable selection between EPDM vs. silicone rubber materials?
To guide you in your decision-making and to ensure you make the right choice, here are some of the most critical factors you should consider.
Cost Implication
When deciding on which rubber material item to go for between EPDM and silicone, cost analysis is critical.
So, if cost-effectiveness is your primary consideration, then EPDM material is your ideal choice.
Desired Operation Temperature Range
You must take note of the desired temperature range that you require your material to operate effectively.
For standard or medium temperature range operations, you will be safe choosing a suitable silicone rubber solution.
However, in an environment where a wide temperature range is desirable, or where exposure to extreme temperatures is expected, EPDM material is your better option
Chemical Resistance
Because both EPDM and silicone are resistant to chemical resistance, your choice should now be based on your required level of resistance.
For applications with low to medium exposure to chemicals or solvents, silicone rubber material or seal will be your best selection.
In special instances where high-level exposure to chemicals such as acids, alkalis, and various solvents is prevalent, your ultimate industrial choice is EPDM material.
Weather Resistance, UV Resistance, and Durability
Both EPDM and silicone offer excellent resistance to weather and UV light resistance, with EPDM taking the lead.
So, for outdoor applications especially for roof sealing requirements where excellent water resistance is also critical, choosing a suitable EPDM material such as EPDM roof membrane is highly suitable.
However, for general-purpose applications such as window or door seal, go for silicone rubber option.
Application Flexibility
While some application areas may be rigid, others demand flexibility.
This is especially true when parts are either moving or are under constant strain.
Because silicone is more flexible than EPDM it is the winning choice.
Desired Durability
If your major concern is selecting a material that will last much longer, then choosing EPDM rubber material will set you in the right application course.
However, if general durability is important but not critical, silicone rubber material will effectively fulfill your requirement.
Installation Ease
In some instances, all you need is a quick and instant sealing or insulation rubber solution. Your better choice in this instance is silicone because of its installation ease.
Color Preference
While both EPDM and silicone and color stable, your application color requirements may determine the material to go for.
For instance, if your project requires a wide range of colors, then you may choose silicone rubber material instead of EPDM. This is because silicone offers a wide range of colors that you can conveniently choose from.
Conclusion
As already noted, both EPDM and silicone have their strengths and limitations. Therefore, before making any purchase decision, you must weigh both their advantages and disadvantages.
It is important to note that both EPDM and silicone offer good resistance to chemicals and water.
Because EPDM has high resistance to heat, ozone, and UV light, it is a perfect solution for your outdoor applications.
Silicone will suit your general applications including in extreme temperature environments, and where flexibility is critical.
It is important to note that both EPDM and silicone come in different forms and grades.
So, when making your comparisons of EPDM vs. silicone solution, ensure that the specification of the material you are assessing is also suitable for your application environment.
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