acrylonitrile-butadiene rubber 化学特性,用途語,生産方法
解説
NBR（acrylonitrile-butadiene rubberの略），またはニトリルゴムとも。アクリロニトリルとブタジエンの共重合によって得られる合成ゴム。耐油性，耐摩耗性が天然ゴムより高く，工業用機器，自動車部品の送油管，パッキン，シールなどに不可欠。もともと天然ゴムの産出地を自国領土・植民地に持たなかったドイツで1930年代に開発され，ブナNと名づけられ（後ペルブナン），米国ではGR-Aと呼ばれた。ベンゼン，四塩化炭素以外の溶剤に耐える。→スチレン・ブタジエンゴム→関連項目合成ゴム
株式会社平凡社 百科事典マイペディアについて 情報
説明
Nitrile rubber (NR) is a copolymer of butadiene and acrylonitrile. It is produced in different ratios varying from 25:75 to 75:25. The manufacturer’s designation should identify the percentage of acrylonitrile. Nitrile rubber under the common trade name Buna? N is well known for its excellent resistance to oils and solvents owing to its resistance to swelling when immersed in mineral oils. Moreover, its chemical resistance to oils is proportional to the acrylonitrile content. However, it is not resistant to strong oxidizing chemicals such as nitric acid, and it exhibits fair resistance to ozone and to UV irradiation which severely embrittles it at low temperatures. Nitrile rubber is used for gasoline hoses, fuel pumps diaphragm, gaskets, seals and packings (e.g., o-rings) and finally oil-resistant soles for safety work shoes.
化学的特性
(Medium acrylonitrile) D (polymer)
0.98, tensile strength (psi) 1000–3000, elongation
(%) 100–700, maximum service temperature 121–
148C. Combustible.
使用
(High acrylonitrile) Oil well parts, fuel-tank liners, fuel hoses, gaskets, packing oil seals, hydraulic
equipment.
(Medium acrylonitrile) General-purpose oil-resistant
applications, shoe soles, kitchen mats, sink topping, and printing rolls. (Low acrylonitrile) Gaskets, grommets, and O-rings (flexible at a very low
temperature), adhesives. Fuel binder in solid rocket
propellants.
定義
(acrylonitrile rubber; acrylonitrilebutadiene rubber; nitrile-butadiene rubber;
NBR). A synthetic rubber made by random
polymerization of acrylonitrile with butadiene
by free radical catalysis. Alternating copolymers
using Natta–Ziegler catalyst have been developed.
Approximately 20% of the total is used as latex;
also available in powder form. Its repeating structure may be represented as –CH2CH=CHCH2CH2
CH(CN)–.
工業用途
Nitrile butyl rubber (NBR) has excellent resistance to mineral and vegetable oils, but relatively poor resistance to the swelling action of oxygenated solvents such as acetone, methyl ethyl ketone, and other ketones. It has good resistance to acids and bases except those having strong oxidizing effects. Resistance to heat aging is good, often a key advantage over natural rubber. With compounding, nitrile rubbers can provide a good balance of low creep, good resilience, low permanent set, and good abrasion resistance.
Tear resistance is inferior to that of natural rubber, and electrical insulation is lower. Uses of NBR include carburetor and fuel-pump diaphragms and aircraft hoses and gaskets. In many of these applications, the nitriles compete with polysulfides and neoprenes.
An outstanding feature of nitrile rubber is its compatibility with many different types of resins permitting it to be easily blended with them. In combination with phenolic resins it provides adhesives with especially high strengths. Nitrile rubber phenolic resin solvent solutions are used in shoe sole-attaching adhesives, for structural bonding in aircraft, adhering automotive brake lining to brake shoes, and many other industrial applications. The ratio of butadiene to acrylonitrile in the commercially available rubbers ranges from a low of about 20% to as high as 50% acrylonitrile. The various grades are usually referred to as high, medium-high, medium-low, and low acrylonitrile content.
acrylonitrile-butadiene rubber 上流と下流の製品情報
原材料
準備製品