Types of High-Temperature Gasket Materials

Like Michelangelo sketching on the ceiling of the Sistine Chapel, you’ve got your perfect design ready to go. But what happens when one of your gaskets can’t handle the heat?

The best version of your gasket needs a suitable material that won’t fail under the strain of a hot application. As a converter that’s been working with high-temp gasket materials for over 40 years, Strouse has a leg up on material selection. 

By the end of this article, you should know your high-temp gasket options and feel confident pursuing the next steps of your project. 

Types of Heat-Resistant Gasket Materials

Your project requires durable materials to function, which starts with a material’s maximum operating temperature. Let’s review common high-temperature seal materials.

MATERIAL	TEMPERATURE RANGE	COMMON USES
Nitrile Rubber	-40°F to 212°F	Fuel pumps and other automotive and industrial applications
Neoprene	-40°F to 230°F	Battery housings
EPDM	-40°F to 250°F	Applications that come into contact with salts, potassium, or nitrogen
Silicone Rubber	-67°F to 400 or 500°F	HVAC system, door, oven, and medical equipment seals

Below, we’ll dive deeper into these common high-temperature gasket materials and how to pick between them.

#1: NITRILE RUBBER (BUNA-N)

Nitrile rubber, also known as NBR or Buna-N, ranges from -40 degrees Fahrenheit to 212 degrees Fahrenheit.

• Automotive and industrial manufacturers often use nitrile rubber gaskets for fuel pumps and other applications.
• The most significant advantage of nitrile rubber for gasketing is its resistance to fuels, gases, and oils.

#2: NEOPRENE

Neoprene can withstand temperatures from -40 degrees Fahrenheit to 230 degrees Fahrenheit. Manufacturers often use it for low- to mid-temperature applications.

• High corrosion resistance
• Neoprene gaskets are a popular material for battery housing
• Resistant to moisture, UV light, and other environmental factors
• Used for a wide range of indoor and outdoor applications

#3: EPDM

When you need a synthetic rubber polymer that lasts from -40 degrees Fahrenheit to 250 degrees Fahrenheit, EPDM is worth your consideration.

• Consider using an EPDM gasket if your application risks contact with salts, potassium, or nitrogen, as it is resistant to these substances.

#4: SILICONE RUBBER

Silicone rubber is an extremely common gasket material due to its wide temperature range of -67 degrees Fahrenheit to 400 or 500 degrees Fahrenheit.

• Silicone rubber gaskets are heat-resistant and help dissipate heat in an application.
• Provide temperature control for devices.
• They are challenging to melt and are used to seal HVAC systems, doors, ovens, and medical equipment.

Additional Factors Affecting Your Gasket Material Choice

Gasketing material requirements for heat resistance may depend on:

• Your material’s thickness
• The stress it encounters
• The length of heat exposure

In addition, achieving tight die-cut tolerances in your heat-resistant gasket can be more challenging and more expensive depending on the material. When a thick material meets a blade, it compresses, altering the cut's shape. Therefore, the thickness of foams and soft rubbers (common in heat-resistant applications) makes them more difficult to cut and process during converting.

High-Temperature Gasketing Applications

You might be surprised to learn that you encounter many gasket materials for elevated-temperature applications in your day-to-day work.

i. ENGINE GASKETS

• The engines of airplanes, trucks, boats, cars, and other vehicles generate significant heat, and their sealing components must withstand it.
• Materials such as neoprene or nitrile rubber are temperature- and corrosion-resistant, making them ideal for use around petroleum derivatives.

ii. CONDUCTIVE GASKETS

• Many devices or electrical systems, such as EV batteries, are built with conductive gaskets.
• Large electrical systems generate significant heat and risk overheating, which is where heat-resistant and heat-dissipative materials come in.
• Die cut gaskets inside EV batteries seal gaps and bond together inner electrical components.
• EV gaskets are consistently exposed to battery heat and are often used to join components to prevent overheating.

iii. BATTERY HOUSING GASKETS

• Battery housing gaskets prevent any particles or liquids from reaching a device’s inner mechanisms.
• Part of the role of battery housing gaskets is to reduce the risk of corrosion while withstanding the high heat of electronics.
• That’s why the aforementioned resistant materials (like neoprene) serve as long-term solutions.

iv. HOT WATER PIPING & STEAM GASKETS

• Installing a gasket between two flanges or connecting pieces creates a static seal that strengthens the connection and prevents leakage.
• Hot water piping gaskets must maintain a seal despite temperature changes.
• Steam gaskets must maintain a seal while withstanding extreme heat and high pressure.
• They are non-reusable because they have been compressed for a long time and could crack or fail once removed.

v. OUTDOOR GASKETS

• Weathering and waterproofing are critical factors to consider when selecting outdoor gasket material.
• Automotive, electrical, and HVAC gaskets often endure weathering and other outdoor conditions.
• Materials such as EPDM rubber, which withstand UV, ozone, and oxidation, are popular choices for high-temperature outdoor gaskets.

Finding the Right High-Temp Gasket Material

In most cases, you’ll be able to find multiple gasketing materials that meet your application’s temperature limit. So, how do you narrow them down? Firstly, ask yourself the following questions.

Questions to Ask When Selecting Gasket Materials
1.	What is the maximum temperature of your application?
2.	At what temperature are you applying the gasket?
3.	Which properties are you looking for (e.g., flexibility/rigidity, expected lifetime, adhesive ability, etc.)?
4.	What substances does it need to resist?
5.	Do you pay multiple manufacturers for slitting, cutting, printing, packaging, etc.?

Once you’ve further narrowed your potential materials list, you’ll want to start sampling the materials in your application—ideally using accurate prototypes that mimic your product’s actual performance.

This is where Strouse’s Sample Express comes into play. You’ll be able to test different materials quickly and accurately to determine whether they will fit within your intended project.

Materials account for 70-80% of converting costs, and finding a suitable material is essential to your product's function, so the last thing you want to do is waste your time and money. Get a sample today and find a material that functions in context.

If you’re interested in reading more about gasket product development, see the sealing solutions in our Learning Center.

Originally published: August 8, 2023