Nitrile (Buna-N) Sponge


Nitrile (Buna-N) Sponge Custom Fabricated To Your Exact Specifications – Gaskets, Seals, Pads and More

SRP is a leading converter of closed cell sponge rubber materials such as Nitrile (Buna-N) sponge rubber. We manufacture high-quality custom Nitrile (Buna-N) sponge rubber gaskets, seals, and other products for a variety applications and industries to companies around the world.

Nitrile (also known as Buna-N) closed cell sponge rubber is an excellent gasket material for sealing applications that require oil and UV resistance. Nitrile has excellent resistance to oil, gasoline, solvents, mineral and vegetable oils, hydraulic fluid, and fuels. It is recommended for applications that require good oil and grease resistance as well as moderate ozone resistance, with compounding, it is possible to get a fairly good balance between low creep, good resilience, low permanent set and good abrasion resistance.

Nitrile is superior to most elastomers with regard to compression set or cold flow, tear, and abrasion resistance. Nitrile resists acids and bases with exception to those having strong oxidizing effects. Nitrile is resistant to a broader range of aromatic hydrocarbons than neoprene. Resistance to heat aging is good. Nitrile rubber material is able to maintain its properties in commercial or industrial applications where temperatures range from -40°F to +275°F.

Nitrile has poor resistance to ketones, chlorinated hydrocarbons, and nitro hydrocarbons. It does not have good ozone, oxygen or sunlight resistance without the addition of special additives. Nitrile’s low temperature resistance is inferior to natural rubber, and although nitrile can be compounded to give improved performance in this area, the gain is normally at the expense of oil and solvent resistance.

Conversely, with higher acrylonitrile contents, the solvent resistance is increased but low temperature flexibility is decreased. Nitrile, like SBR, does not crystallize on stretching. Thus, reinforcing materials, such as carbon blacks, are required to obtain high strength. Tear resistance is inferior to that of natural rubber and electrical insulation is lower.

Nitrile is commonly used for industrial and automotive applications, in products such as:

  • fuel and oil handling hoses
  • petroleum oil seals
  • grommets
  • hydraulic fluid seals
  • transmission fluid seals
  • shock and vibration mounts

Typical applications of the premium grades of NBR include: carburetor gaskets and aircraft hose gaskets. The commercial grades of NBR are usually blends of NBR with other polymers. These less costly blends accommodate less demanding applications where oils and heat are prevalent. Ozone resistant nitriles are recommended when there is extended exposure to air and ozone. All closed cell sponge materials can be supplied with a pressure sensitive adhesive.

Closed Cell Nitrile (Buna-N) Sponge Rubber Material Data Sheets:


SRP: Building Relationships through Converting Solutions Since 1951

We provide our customers with everything from material sampling and product prototyping to full manufacturing, packaging, and delivery. We provide value to our customers by delivering exceptional customer service, engineering solutions, and quality products to meet their every need. All sponge gaskets products can be supplied with Pressure Sensitive Adhesives. Many of these materials meet industry specs for the military, automotive, and aerospace industries.

For more information, you can reach SRP at or 847-593-5630.