What is HNBR

Hydrogenated Nitrile Butadiene Rubber, or HNBR, is a high-performance rubber substance with many uses and exceptional durability. It is a modified nitrile rubber (NBR) that has undergone hydrogenation to increase its resistance to age, heat, and chemicals. In many different sectors, HNBR is commonly utilized. We shall explore the features, benefits, and use cases of HNBR in this post.

What is HNBR used for?

Because of its special qualities, HNBR (Hydrogenated Nitrile Butadiene Rubber) is employed in a lot of different applications. Among the frequent applications for HNBR are:

Automotive Industry: HNBR is widely applied in a variety of automotive applications. It is utilized in parts that need to have exceptional resistance to heat, oil, and chemical exposure, such as engine seals, gaskets, O-rings, timing belts, and fuel system components. HNBR is a great option for harsh automotive conditions because of its resistance to automotive fluids and high temperatures.
Oil and Gas Industry: Because of HNBR’s remarkable resistance to oil, fuels, and chemicals, it is commonly used in this industry. It is utilized in O-rings, gaskets, and seals for pipelines and equipment that handle severe chemicals, hydraulic fluids, and petroleum products. HNBR is suited for oil refining and offshore drilling because to its resilience to hostile conditions and sour gasses.
Industrial Machinery: HNBR is used in a range of industrial equipment and machinery. It is utilized in gaskets, hoses, and seals that are exposed to high pressure situations, chemicals, and hydraulic fluids. Heavy-duty industrial applications benefit greatly from HNBR’s resilience to compression deformation, high tensile strength, and longevity.
Aerospace and Aviation: Because HNBR can tolerate high temperatures, fuels, and hydraulic fluids, it is used in the aerospace and aviation industries. It is utilized in hoses, gaskets, O-rings, seals, and landing gear as well as fuel and hydraulic systems in aviation engines. The aircraft sector favors HNBR because of its resistance to aviation fuels and capacity to continue operating at high altitudes.
Pharmaceutical and Food Processing: HNBR is used in applications where it’s important to be resistant to chemicals, oils, and high temperatures in the pharmaceutical and food processing industries. It is utilized in filtration systems, apparatus that comes into touch with medications and food items, seals, gaskets, and tubing for fluid transmission. These sectors can benefit from HNBR’s superior chemical compatibility and adherence to food-grade requirements.
Renewable Energy: Systems that generate electricity from solar and wind power employ HNBR. It is used in gaskets, O-rings, and seals that offer defense against UV rays, weathering, and adverse environmental circumstances. HNBR is appropriate for renewable energy applications because of its resistance to ozone and capacity to retain flexibility and sealing performance over long periods of time.

What is the difference between nitrile and HNBR?

Although hydrogenated nitrile butadiene rubber (HNBR) and nitrile rubber (NBR) are synthetic elastomers with comparable chemical compositions, they differ greatly in terms of their uses and characteristics. The following are the main distinctions between HNBR and NBR:

Chemical Structure: Hydrogenated nitrile butadiene rubber (HNBR) is a modified form of nitrile rubber (NBR), which is a copolymer of butadiene and acrylonitrile. The butadiene segments in NBR can be hydrogenated completely or partly to form HNBR, which has better qualities than NBR.
Heat Resistance: When it comes to heat resistance, HNBR outperforms NBR. HNBR can tolerate temperatures up to 150°C (302°F), or even higher in some circumstances, while NBR begins to deteriorate at temperatures over 100°C (212°F). The process of hydrogenation in HNBR improves its thermal stability.
Chemical Resistance: HNBR provides superior resistance to chemicals, oils, and fuels compared to NBR. The process of hydrogenating butadiene segments in HNBR increases its resistance to strong chemicals, hydraulic fluids, solvents, and a variety of oils by lowering its sensitivity to chemical assault.
Mechanical qualities: Compared to NBR, HNBR has better mechanical qualities. HNBR offers better tensile strength, tear resistance, and abrasion resistance compared to NBR. Furthermore, it maintains its flexibility and sealing power throughout a wider temperature range.
Swelling Resistance: HNBR displays superior resistance to swelling in oil and fuel conditions compared to NBR. This characteristic is crucial in situations where the elastomer must continue to function as a sealant and preserve its dimensional stability when in contact with fuels and oils.
Cost: In general, NBR is less expensive than HNBR. Because of the increased complexity and expense of the manufacturing process brought about by the hydrogenation process, HNBR is a more expensive material.
Applications: NBR is frequently used in seals, gaskets, hoses, and O-rings in automotive, industrial, and hydraulic systems—applications that call for resistance to oil and gasoline. Due to its improved qualities, HNBR is used for more demanding applications, including as high-temperature industrial applications, fuel systems, oil and gas equipment, automobile engine seals, and aerospace components.

Is HNBR ozone resistant?

Indeed, a well-known property of HNBR (Hydrogenated Nitrile Butadiene Rubber) is its exceptional resistance to ozone. The Earth’s atmosphere contains ozone, a highly reactive type of oxygen that over time may erode and degrade a variety of rubber materials. When compared to other elastomers, such as non-hydrogenated nitrile rubber (NBR), HNBR, however, shows high ozone resistance.

HNBR becomes more resistant to ozone attacks as a result of the hydrogenation process. The presence of saturated bonds generated after hydrogenation renders HNBR less vulnerable to ozone damage. Long-term exposure to ozone does not affect HNBR’s ability to function or retain its physical characteristics thanks to this increased resistance.

Ozone resistance makes HNBR a popular choice for applications involving outdoor exposure and ozone concerns. This covers parts used in automobiles, like hoses and seals, where the material can come into contact with ozone-rich air. It is also used in other sectors of the economy, such aircraft, where components exposed to high altitudes require ozone protection.

HNBR has strong ozone resistance, however it’s crucial to remember that over time, deterioration may still occur to some extent if it is exposed to high ozone concentrations or harsh ozone exposure circumstances. Therefore, in particularly demanding ozone situations, additional design considerations—like protective coatings or correct sealing—may be required.

Is HNBR gasoline resistant?

The resistance of Hydrogenated Nitrile Butadiene Rubber (HNBR) to gasoline and other hydrocarbon-based fuels is good. HNBR is a recommended elastomer for applications in the automotive, oil and gas, and other sectors where contact with gasoline is frequent because to its outstanding resistance to a variety of lubricants, fuels, and solvents.

A variety of hydrocarbons, including additives and aromatic chemicals, are often found in gasoline. The hydrogenation method and chemical makeup of HNBR provide it resistance to these chemicals. Long-term exposure to gasoline won’t significantly degrade HNBR’s physical characteristics or sealing effectiveness.

HNBR is appropriate for a variety of automobile parts, including gaskets, hoses, O-rings, and fuel system seals because of its resistance to gasoline. It is utilized in components that come into touch with gasoline, such as fuel injectors, fuel pumps, and fuel tanks. Maintaining the integrity and functionality of these components depends on HNBR’s resistance to swelling, deterioration, and penetration in the hostile environment of gasoline.

What are the mechanical properties of HNBR?

Tensile Strength: HNBR is able to bear large pulling or stretching pressures without cracking because of its high tensile strength. The normal range of its tensile strength is 10 MPa (megapascals) to 25 MPa, contingent upon the particular grade and formulation.
Elongation at Break: The term “elongation at break” describes a material’s capacity to extend before breaking. The elongation of HNBR generally ranges from 150% to 300% at break. This characteristic suggests that before HNBR reaches its breaking point, it can experience considerable deformation.
Tear Resistance: When exposed to mechanical loads, HNBR has exceptional tear resistance, which means it can withstand the spread of cracks or rips. Usually, it has a rip strength between 20 and 40 N/mm.
Compression Set: The capacity of a material to regain its previous shape following compression or deformation is referred to as compression set. Because HNBR has a high degree of compression set resistance, it can withstand prolonged compression without losing its shape or sealing ability.

Hardness: Using a Shore A scale, HNBR may be mixed to produce several degrees of hardness. HNBR compounds come in harsh grades (Shore A 90 or above) and comparatively gentle grades (Shore A 60). The application’s specifications are used to establish the particular hardness.
Abrasion Resistance: Because HNBR has a high level of abrasion resistance, it may be used in situations where the material is scraped or rubbed against other surfaces. Its resistance to friction-induced wear increases its lifetime and endurance.
Flexibility: HNBR can withstand movement and deformation without compromising its structural integrity or sealing capacity since it remains flexible over a broad temperature range. This characteristic is especially crucial in dynamic applications where the material must often bend or flex.

These mechanical characteristics make HNBR suitable for a variety of tough applications, such as industrial components that need to be resistant to heat, chemicals, and mechanical stress, and automotive seals, gaskets, O-rings, and hoses. It is imperative to refer to the manufacturer’s requirements for the intended application as different grades and formulations of HNBR may display differences in mechanical characteristics.

What is the maximum temperature for HNBR?

Hydrogenated nitrile butadiene rubber’s (HNBR) maximum temperature tolerance varies according on the grade, formulation, and application specifications. But generally speaking, HNBR has good heat resistance and can withstand temperatures as high as around 150°C (302°F) or more.

When HNBR is hydrogenated, it becomes more thermally stable than when non-hydrogenated Nitrile Rubber (NBR). HNBR retains its mechanical characteristics and sealing efficacy at temperatures that are higher without experiencing appreciable deterioration.

It’s crucial to remember that the highest temperature for HNBR can change depending on a number of variables, including the length of exposure, the particular chemical environment, and the existence of other outside variables like pressure or stress. Over time, rapid aging or a decline in HNBR’s performance may result from constant exposure to temperatures at or close to the upper limit of its operating range.

What are the advantages of HNBR?

Improved Heat Resistance: HNBR demonstrates greater heat resistance compared to non-hydrogenated Nitrile Rubber (NBR). It can endure greater temperatures without substantial deterioration, making it useful for applications where increased temperatures are encountered.
Outstanding Chemical Resistance: HNBR has outstanding resistance to a variety of chemicals, such as hydraulic fluids, fuels, oils, solvents, and several industrial chemicals. Even in harsh conditions, HNBR may continue to function and retain its integrity thanks to its chemical resistance.
Better Mechanical qualities: When compared to NBR, HNBR has better mechanical qualities. It is more resilient and able to handle mechanical strains and wear thanks to its increased tensile strength, tear resistance, and abrasion resistance.
Resistance to UV Radiation, Ozone, and Weathering: HNBR is a useful material for outdoor applications because of its strong resistance to these factors. It is resistant to severe environmental exposure without suffering appreciable deterioration or loss of physical characteristics.
Excellent Compression Set Resistance: HNBR keeps its form and sealing qualities even after prolonged compression or deformation. Because of its low compression set, it may rapidly regain its normal shape when the compressive force is removed.
Wide Temperature Range: HNBR can work well in both low- and high-temperature conditions since it is flexible and keeps its sealing capacity across a wide temperature range.
Versatility: Depending on the needs of the application, HNBR may be formed to obtain a broad variety of hardness levels, from comparatively soft to tougher grades. Its adaptability makes it suitable for usage in a wide range of industries, including as the automotive, oil & gas, industrial, and aerospace sectors.
Resistance to Swelling: In situations including gasoline and oil, HNBR shows outstanding resistance to swelling. When it comes into contact with oils, fuels, and other abrasive substances, it keeps its sealing ability and dimensional stability.