Properties of Nitriles

The dipole moment of 2-chloro-3-cyanopyrazine has been determined as 3.44D in dioxane (749). Polymers have been prepared from 2,3-diamino-5,6-dicyano- 

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Effect of the phenolic resin content in the mechanical properties of nitrile rubber... 

Salame, M., Transport Properties of Nitrile Polymers, Amer. Chem. Soc.,... 

The low temperature properties of nitriles can be improved by the use of suitable plasticisers, e.g., ester plasticisers. 

Specific properties of nitrile oxides depend on the structure of the functional group, which have highly polarized C-N and N-0 bonds (Scheme 1.1). 

The second term, which outweighs the first one, is said to arise from an SN 2 contribution in the reaction mechanism. These observations have been taken as evidence in favour of the proposed -donating properties of acetonitrile,6 and it was stated that MeCN is as effective a nucleophile towards Mo(CO)6 as triphenylphosphine. The mww-labilizing properties of nitriles, on the other hand, are less pronounced than those of, for example, carbonyl or dimethylphenylphosphine. This is consistent with the weak -acceptor character of nitriles. 

Marier-Greiner, U.H., Obermaier-Skrobranek, B.M.M., Estermaier, L.M., et al. 1991. Isolation and properties of nitrile hydratase from the soil fungus Myrothecium verrucaria that is... 

Japanese workers were the first to use the reactive properties of nitrile compounds to synthesize thiazolo[3,2-a]pyridin-3(2//)-ones (77S839). Ethyl a-cyanocinnamate (88, R = Ph, R = CO Et) reacts with ethyl mer-captoacetate in the presence of triethylamine to give 5-amino-2-benzyli-dene-6,8-bis (ethoxycarbonyl )-7-phenyl-7//-thiazolo [3,2-n]pyridin-3(2//)-one (89, R = R- = Ph, R = R = C02Et), which is also obtained from the reaction of 5-benzylidene-2-ethoxycarbonylmethyl-2-thiazolin-4-one (90a) with ehtyl a-cyanocinnamate (77S839). Reaction of 90a,b with ben-zylidenemalononitrile (88, R- = Ph, R" = CN) and of 90c with ethyl a-cyanocinnamate furnish the respective bicyclic compounds 89 [83ZN(B)781] (Scheme 21). Similar results were also obtained from 88 (R = furan-2-yl-or thiophen-2-yl) (86M105). 

Nitrile rubbers possess outstanding oil-resistant properties. Explain the following variation in properties of nitrile rubber. 

Acrylonitrile Content in Copolymer (%) Properties of Nitrile Rubber... 

Oil Resistance The primary property of nitrile rubber is oil resistance and it is this factor, in conjimction with its excellent physical properties, which account for much of its commercial use. Oils generally attack rubbers by causing them to swell. 

Ibrahim, S., M.Abu-Abdeen and Yassin, A. (2006). Effect of batio3 on the mechanical properties of nitrile-butadien rubber (nbr) vulcanizates, Egypt. J. Solids 29. 

This is one of the most important synthetic thermoplastic elastomers. Nitrile rubber is a copolymer of butadiene and acrylonitrile. The copolymer usually contains enough acrylonitrile (>25%) so that good resistance to oil and grease can be obtained. Adhesive properties also increase with increasing nitrile content. These adhesives are used to bond vinyls, other elastomers, and fabrics where good wear, oil, and water resistance are important. Compatibility with additives, fillers, and other resins is another advantage of this material.Table 5.1 summarizes the properties of nitrile rubber. 

M. Balachandran and S. S. Bhagawan, Mechanical, Thermal, and Transport Properties of Nitrile Rubber-Nanocalcium Carbonate Composites, Journal of Applied Polymer Science, 2012, 126, 1983. 

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