Nitrile rubber technology

Hofmann, W., 1984. Recent developments in nitrile rubber technology. Prog. Rubber Technol. 46, 43-84. 

Fig. 5 Schematic description of CNT/polymer composites, which prepare by using nitrile rubber technology...

The research in this area has a great potential from scientific and technological aspects and requires further exploration. However, the reported attempts are a welcoming endeavor to hydrogenate nitrile rubber in latex form. 

The accelerated sulfur vulcanization of general-purpose diene rubbers (e.g., NR, styrene-butadiene rubber [SBR], and butadiene rubber [BR]) by sulfur in the presence of organic accelerators and other rubbers, which are vulcanized by closely related technology (e.g., ethylene-propylene-diene monomer [EPDM] mbber, butyl rubber [HR], halobutyl mbber [XIIR], nitrile rubber [NBR]) comprises more than 90% of all vulcanizations. 

Gaskets - [cross-reference entry] (Vol 12) -asbestos m [ASBESTOS] (Vol 3) -magnets m [MAGNETIC MATERIALS - BULK] (Vol 15) -NBRm [ELASTOMERS, SYNTHETIC - NITRILE RUBBER] (Vol 8) -for pressure vessels [HIGH PRESSURE TECHNOLOGY] (Vol 13)... 

Chemical modification of polymers continues to be an active field of research [1-5]. It is a common means of changing and optimising the physical, mechanical and technological properties of polymers [5-7]. It is also a unique route to produce polymers with unusual chemical structure and composition that are otherwise inaccessible or very difficult to prepare by conventional polymerisation methods. For example, hydrogenated nitrile rubber (HNBR) which has a structure which resembles that of the copolymer ethylene and acrylonitrile, is very difficult to prepare by conventional copolymerisation of the monomers. Polyvinyl alcohol can only be prepared by hydrolysis of polyvinyl acetate. Most of the rubbers or rubbery materials have unsaturation in their main chain and/or in their pendent groups. So these materials are very susceptible towards chemical reactions compared to their saturated counterparts. 

Hydrogenation is an important method of chemical modification of elastomers. Because of the absence of carbon-carbon unsaturation, hydrogenated elastomers have good resistance to oxidative and thermal degradation, improved weatherability and good resistance towards chemicals and fluids [5-7]. Nitrile rubber (NBR) is a specialty rubber, and because of its oil resistance properties, it has been used in oil-wells and the automotive industry. Hydrogenation of NBR has been studied extensively because of its technological importance [16-19]. 

Mackey, D., and A. H. Jorgensen. 1999. Elastomers, synthetic (nitrile rubber). In Kirk-Othmer encyclopedia of chemical technology, 4th ed., 687-688. New York McGraw-Hill. 

Hoffmann, W. 1964. Nitrile rubber, rubber chemistry and technology, a rubber review for 1963, 154-160. San Francisco, CA John Wiley Sons. 

The oil resistance and chemical resistance of nitrile rubber is generally superior to that of EPDM rubbers. However, the highly polar nature of acrylonitrile comonomer is responsible for the high incompatibility between nitrile rubber and polypropylene. The dispersability and the stability of nitrile rubber dispersions in the polypropylene matrix are poor. Hence a reactive compatibilization technology was used [Coran and Patel, 1983], It consisted of blending a small amount of a low molecular weight amine-terminated butadiene-acrylonitrile copolymer (ATBN,... 

Mackey, D., Jorgensen, A.H., 2000. Nitrile rubber. In Kirk-Othmer (Ed.), Encyclopedia of Chemical Technology. Wiley, New York, p. 1-15. 

The lower left qnadrant represents the simple blends. One type of TPE blend is the TPO, which is a simple polymer blend of a rigid thermoplastic polymer with a technologically compatible (not necessarily thermodynamically compatible) elastomeric polymer. Each of the polymeric components exists in its own phase (with its own Tg or The properties of the blend are partly predictable by the properties of the com nents however, the phase morphology is also extremely important. The hard phase must be continuous for the blend to be thermoplastic. Commercial TPO blends include those of EPDM rubber with PP or polyethylene (PE). Another type of simple polymer blend is that of poly(vinyl chloride) and nitrile rubber (NBR). This may have been the first useful rubber-plastic blend. 

Polymer blends offer improved performance/cost ratio and flexibility to tailor-made products. Compatible, incompatible, miscible, and immiscible blends are distinguished from each other. Polymer alloys are a commercial blends with improved property balance by use of a compatibilizer. By 1992, the worldwide production of plastics was twice that of steel. The manufacture of polymers would grow by a factor of 10 prior to market saturation. Table 1.1 provided a chronology of events in technology development in the field of polymer blends since the nitrile rubber/gutta percha was blended in 1846 first through the development of PPS/PBT in 1990. 

Trouble shooting in the case of products made from fluororubbers, polyurethane rubbers, hydrogenated nitrile rubber and silicone rubbers is explained. 2 refs. Articles from this journal can be requested for translation by subscribers to the Rapra produced International Polymer Science and Technology. 

Robinson, H. W., Nitrile Rubber, in Kirk-Oth-mer Encyclopedia of Chemical Technology, 3rd Ed., 8, 534-546, New York, John Wiley and Sons, 1979. 

Figure 6.4 Headspace GC-MS of volatiles from nitrile rubber. Reproduced with permission from J. Sidwell in Proceedings of a Rapra Technology Conference on Medical Polymers, Dublin, Ireland, 2003, Paper 8, p.51. 2003, Rapra...

W. Hoffmann, A Rubber Review for 1963 Nitrile Rubber, Rubber Chemistry and Technology, Volumes XXXVI and XXXVII, December 1963 and April 1964. 

D. Seil and F.R. Wolf, Nitrile and Polyaciylic Rubbers, in M. Morton (ed.) Rubber Technology, Chapter 11, 3rd edition. Van Nostrand Reinhold Company, New York. 

The scale-up goal was achieved and the DevulCOi devulcanisation technology was successfully transferred to a number of sulfur-cured rubbers, including nitrile rubber, EPDM rubber and NR. In addition, the results of the evaluation of the performance of the DevulCOi rubber in tyre retread compounds were encouraging. A more extensive description of these two projects and the results of the manufacturing trials that were imdertaken during them, is provided in Chapter 5, Section 5.2.2.I. 

Transfer of DevulC02 technology from tyre rubber to sulfur-cured GRG products, e.g., nitrile rubber matting and ethylene-propylene-diene monomer (EPDM) rubber automotive weather strip. 

A comprehensive survey of nitrile rubber was published by Hofmann in 1963, since then Dunn et al have described further technological progress and prospects of development. In this chapter the present position of NBR is described in general terms and the factors which could affect the importance of NBR in the future are indicated. NBR latex is not considered here. 

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