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Hydrogenation of nitrile rubber

This chapter mainly aims at describing the various methods and processes developed for hydrogenation of nitrile rubber. The characterization, physical properties, and application of hydrogenated nitrile rubber are also discussed. Another small section on hydroformylation of nitrile rubber has been included. [Pg.556]

Table 3 Heterogeneous Catalytic Hydrogenation of Nitrile Rubber... Table 3 Heterogeneous Catalytic Hydrogenation of Nitrile Rubber...
It can be summarized from the available data in Table 3 that supported palladium catalysts selectively hydrogenated carbon-carbon double bonds in the presence of the nitrile group in NBR. However, there is no detailed fundamental study on heterogeneous catalytic hydrogenation of nitrile rubber in the literature that can provide an insight into the reaction. The available information is limited since most of the literature is patented. [Pg.559]

Table 6 Hydrogenation of Nitrile Rubber in Presence of Palladium Catalyst... Table 6 Hydrogenation of Nitrile Rubber in Presence of Palladium Catalyst...
The available studies indicate that diimide has been used as a reducing agent for the preparation of HNBR. It has been used mainly as an alternative for hydrogenation of nitrile rubber latex. The use of diimide to hydrogenate low-molecular weight olefines is well known in the organic literature [93]. Diimide can be conveniently generated in situ by thermal treatment of solutions of p-tolu-enesulfonyl hydrazide or oxidation of hydrazine. [Pg.567]

Characterization and understanding of the microstructure become important after hydrogenation and hydroformylation of the nitrile rubber since the amount and distribution of the residual double bonds influence the properties of modified rubber. The conventional analytical tools have been used to characterize the elastomers. Spectroscopy is the most useful technique for determination of the degree of hydrogenation in nitrile rubber. [Pg.568]

W02005/080456 Al, Lanxess Inc. Process for the preparation of low molecular weight hydrogenated nitrile rubber EP2028194 Al, Lanxess Deutschland GmbH Metathesis of nitrile rubbers in the presence of transition metal complex catalysts Press release Lanxess - New York Conference, New York City, USA, Monday August 28, 2006, Address by Dr. Ulrich Koemm LANXESS Concepts in Rubber ... [Pg.324]

During the last 15 years several companies have developed hydrogenated grades of nitrile rubber to both improve its thermal stability and solvent resistance. Although the hydrogenation of a poly diene backbone was done as early as the 1920s, real commercial products with acrylonitrile were not introduced until the mid-1980s.59... [Pg.708]

Polyacrylate, designated ACM by ASTM, is a cost-effective family of heat and oil resistant polymers with a long history of use by the automotive industry, and to a much lesser extent for mechanical goods. These polymers operate very well at 150°C to 175°C in oU, hence are used in appheations operating above the capability of nitrile rubber, (NBR). Polyacrylate is also more cost-effective than hydrogenated nitrile (HNBR) and fluoroelastomer (FKM), thus may be used where the properties of the ACM meet all of... [Pg.155]

Hydrogenated nitrile rubbers were introduced in the mid-1980s as Therban by Bayer. The initial grade had an acrylonitrile content of only 17% instead of approx. 34% in conventional NBR. Whilst non-sulphur-curing systems such as the use of peroxides with triallyl cyanurate or isocyanurate are necessary, the saturated rubber has a number of advantages over NBR. These include improved... [Pg.294]

Butyl phenolic resin is a typical tackifier for solvent-borne polychloroprene adhesives. For these adhesives, rosin esters and coumarone-indene resins can also be used. For nitrile rubber adhesives, hydrogenated rosins and coumarone-indene resins can be used. For particular applications of both polychloroprene and nitrile rubber adhesives, chlorinated rubber can be added. Styrene-butadiene rubber adhesives use rosins, coumarone-indene, pinene-based resins and other aromatic resins. [Pg.597]

Most rubbers used in adhesives are not resistant to oxidation. Because the degree of unsaturation present in the polymer backbone of natural rubber, styrene-butadiene rubber, nitrile rubber and polychloroprene rubber, they can easily react with oxygen. Butyl rubber, however, possesses small degree of unsaturation and is quite resistant to oxidation. The effects of oxidation in rubber base adhesives after some years of service life can be assessed using FTIR spectroscopy. The ratio of the intensities of the absorption bands at 1740 cm" (carbonyl group) and at 2900 cm" (carbon-hydrogen bonds) significantly increases when the elastomer has been oxidized [50]. [Pg.640]

The value of AG° at various reaction temperatures and corresponding Kp values are reported in Table 2. It can be understood from Table 2 that the formation of hydrogenated nitrile rubber from nitrile rubber is thermodynamically feasible. [Pg.557]


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