NBR Rubber - Properties - Butadiene-Acrylonitrile Rubber
NBR rubber is a rubber compound that stands out among other rubbers by the fact that its resistance to oils, fuels, and fats increases with the increasing ACN content. However, its resistance to low air temperatures decreases. When NBR is mixed with PVC in the production process, an ozone-resistant compound can be obtained. When combined with phenolic resin, it results in a flexible rubber with good stretchability and resistance to hot water.
What does the abbreviation NBR stand for?
NBR, or nitrile, is one of the most popular rubbers. It is often referred to as oil-resistant rubber. Other names for this rubber that can be found on the market include:
- butadiene-acrylonitrile rubber,
- acrylonitrile-butadiene rubber,
- in English: nitrile butadiene rubber.
NBR is a type of elastomer, a product of the copolymerization of butadiene and acrylonitrile.
From a chemical point of view, it is a copolymer of butadiene and acrylonitrile.
NBR rubber: properties of oil-resistant rubber
Depending on the amounts of the above-mentioned chemical compounds used and the change in their percentage share in the mixture, it is possible to manipulate the resistance to oils and low temperatures. The temperature parameters at which you can work with this rubber range from -30 degrees Celsius to 100 degrees Celsius. The physical properties of the rubber include resistance to motor oils, fuel oils, and transformer oils. The rubber also has high durability against the use of greases, hydraulic fluids, and aliphatic hydrocarbons. It will perform well in conditions involving propane, butane, and gasoline. It is also praised for its durability in the presence of alcohols, aqueous salt solutions, and diluted acids and bases at moderate temperatures. In terms of water temperature, it will work well in conditions up to 60 degrees Celsius. However, NBR is not well resistant to oils and greases containing silicon, brake fluids based on glycol, and hydraulic fluids of the HFD type. The rubber will also not be resistant to concentrated acids, alkalis, and aromatic hydrocarbons. Problematic will also be the use in its presence of chlorinated hydrocarbons, with benzene being an example. Esters can also degrade the structure of NBR.
The detailed properties of the rubber are as follows:
- it has low resistance to atmospheric factors and ozone - an exception is its mixture with PVC,
- it is very tear-resistant,
- according to various sources, the thermal resistance ranges from -50 to 105 degrees Celsius,
- it shows resistance to the action of oils and gasoline,
- it is resistant to aliphatic hydrocarbons,
- it also has durability with light fuel oils, fuels for diesel engines,
- high resistance to non-flammable hydraulic fluids (types HSA, HSB: oil-in-water emulsions, HSC: polyglycol-water mixtures),
- it does not react with diluted acids and bases at not very high temperatures,
- not durable against aromatic and chlorinated hydrocarbons,
- not resistant to the action of HSD: polyesters and chlorinated hydrocarbons),
- no resistance to brake fluids containing glycols in their compositions.
NBR Rubber - Temperature Range
For the NBR rubber compound, most commonly used in O-rings, known to us as o-rings, the following temperature range is provided:
-50 to +105 degrees Celsius, although Rubber Specialists from POWER Rubber recommend its use in the range from -40°C to +90°C
XNBR
XNBR is a reinforced NBR mixture.
Its abbreviation comes from the name containing X: Carboxylated Nitrile (source: www.skf.com), which means Carboxylated Nitrile in Polish.
This mixture has greater resistance than basic nitrile rubber:
- higher abrasion resistance
- greater tear resistance
XNBR Application
The XNBR mixture is used in a wide range of high-tech industries. Polish conditions are not yet ready for the use of this mixture.
For a quotation, please contact: power@powerrubber.com
Acrylonitrile Butadiene Rubber - Application
Nitrile rubber is mainly used in hydraulics and pneumatics. This rubber will create all kinds of seals, O-ring seals. Work involving high pressure, strong compression, and accompanying substances such as oils is a suitable environment for the application of this rubber. In daily life, NBR can be found in tires, inner tubes, and bumpers. Also, shock-absorbing elements are produced from NBR. Their advantage is also in damping vibrations. All hoses for liquid fuels and oils are also made using NBR. Interestingly, linings and printing rollers are also made from this rubber. In the food industry, NBR can be used as a material for conveying hoses. It can also be a sealant for various types of joints.
Plates that undergo NBR vulcanization can be used as washers and gaskets. Their presence with mineral oil will not cause their destruction. Branches of industry dealing with the production of elements for automotive, chemical, machinery, and petrochemical industries have significantly optimized production by using NBR.
The vast properties of NBR mean that laboratory items made of nitrile rubber can also be found. For example, NBR gloves are three times more puncture-resistant than natural rubber gloves.
On the market, you can also find shoes and adhesives containing NBR.
A better mixture with higher properties is the Viton mixture. Check out the article: Viton Rubber - FKM/FPM Rubber Mixture
Rubber products made from NBR rubber: