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POLY-CYANIDES

The next group of poly-substitution products are those containing two or more cyanogen radicalsy (—CN). These correspond exactly to the poly-halogen compounds, from which they may be prepared by the action of potassium cyanide. [Pg.192]

These compounds are characterized by the same properties as the mono-cyanogen compounds. As the latter are known as acid nitriles, because on hydrolysis they yield mono-carboxy acids, so also the dicyanogen compounds are nitriles of the di-carhoxy acids. The symmetri- [Pg.192]

These di-cyanogen and other poly-cyanogen derivatives are of importance only in this connection as nitriles of the poly-carboxy acids sjnA those that are necessary to be considered will be referred to later as we come to them in the study of these acids. The simplest di-cyanogen compound is the gas cyanogen NC—CN, which has been referred to as an example of a radical which exists as such in the free state. [Pg.193]


Poly-cyanides and iso-cyanides Poly-hydroxy compounds or poly-acid alcohols Poly-aldehydes... [Pg.182]

POLYTffiRSCONTAININGSULFUR - POLY(PHENYLENE SULFIDE)] (Vol 19) use of sodium cyanide [CYANIDES] (Vol 7)... [Pg.583]

New PHB materials are composed of Zn-tetraben2oporphyrin—aromatic cyanide—poly (methyl methacrylate) (180) or of tetraphenylporphyrin derivatives dispersed in polymer matrices such as PMMA and polyethylene (181). A survey of such materials has been given (181). [Pg.156]

Polymer Solvent. Sulfolane is a solvent for a variety of polymers, including polyacrylonitrile (PAN), poly(vinyhdene cyanide), poly(vinyl chloride) (PVC), poly(vinyl fluoride), and polysulfones (124—129). Sulfolane solutions of PAN, poly(vinyhdene cyanide), and PVC have been patented for fiber-spinning processes, in which the relatively low solution viscosity, good thermal stabiUty, and comparatively low solvent toxicity of sulfolane are advantageous. Powdered perfluorocarbon copolymers bearing sulfo or carboxy groups have been prepared by precipitation from sulfolane solution with toluene at temperatures below 300°C. Particle sizes of 0.5—100 p.m result. [Pg.70]

Nearly all uses and appHcations of benzyl chloride are related to reactions of the active haUde substituent. More than two-thirds of benzyl chloride produced is used in the manufacture of benzyl butyl-phthalate, a plasticizer used extensively in vinyl flooring and other flexible poly(vinyl chloride) uses such as food packaging. Other significant uses are the manufacture of benzyl alcohol [100-51-6] and of benzyl chloride-derived quaternary ammonium compounds, each of which consumes more than 10% of the benzyl chloride produced. Smaller volume uses include the manufacture of benzyl cyanide [140-29-4], benzyl esters such as benzyl acetate [140-11-4], butyrate, cinnamate, and saUcylate, benzylamine [100-46-9], and benzyl dimethyl amine [103-83-8], and -benzylphenol [101-53-1]. In the dye industry benzyl chloride is used as an intermediate in the manufacture of triphenylmethane dyes (qv). First generation derivatives of benzyl chloride are processed further to pharmaceutical, perfume, and flavor products. [Pg.61]

Abstract In this chapter, the depression mechanism of five kinds of depressants is introduced respectively. The principle of depression by hydroxyl ion and hydrosulphide is explained which regulates the pH to make the given mineral float or not. And so the critical pH for certain minerals is determined. Thereafter, the depression by cyanide and hydrogen peroxide is narrated respectively which are that for cyanide the formation of metal cyanide complex results in depression of minerals while for hydrogen peroxide the decomposition of xanthate salts gives rise to the inhibitation of flotation. Lastly, the depression by the thio-organic such as polyhydroxyl and poly carboxylic xanthate is accounted for in detail including die flotation behavior, effect of pulp potential, adsorption mechanism and structure-property relation. [Pg.112]

In an extension of this work, the reuse of the polymeric catalyst was addressed and several new PE-poly(alkene) glycol copolymers were prepared [68]. Commercially available oxidized polyethylene (CO2H terminated, both high and low molecular weight) was converted to the acid chloride and reacted with Jeffamine D or Jeffamine EDR, and subsequently converted to the tributylammonium bromide salt with butyl bromide. These new quaternary salts were shown to catalyze the nucleophihc substitution of 1,6-dibromohexane with sodium cyanide or sodium iodide. While none of the polymeric quaternary salts catalyzed the reaction as well as tetrabutylammonium bromide, the temperature-dependent solubility of the polymers allowed removal of the polymer by simple filtration. [Pg.252]

Table 10.5 gives the uses of acetone. A very important organic chemical that just missed the top 50 list, methyl methacrylate, is made from acetone, methanol, and hydrogen cyanide. Approximately 1.2 billion lb of this compound is manufactured and then polymerized to poly(methyl methacrylate), an important plastic known for its clarity and used as a glass substitute. The synthesis is outlined as follows. [Pg.175]

Phenylacetamide has been obtained by a wide variety of reactions from benzyl cyanide with water at 250-260° 6 from benzyl cyanide with water and cadmium oxide at 240° 6 from benzyl cyanide with sulfuric acid 7 8 by saturation of an acetone solution of benzyl cyanide with potassium hydrosulfide 9 from benzyl cyanide with sodium peroxide 10 by electrolytic reduction of benzyl cyanide in sodium hydroxide 11 from ethyl phenyl-acetate with alcoholic 12 or aqueous 13 ammonia from phenyl-acetic acid with ammonium acetate 14 or urea 15 from diazoacetophenone with ammoniacal silver solution 16 from phenyl-acetic acid imino ether hydrochloride and water 17 from acetophenone with ammonium poly sulfide at 215° 18 from benzoic acid 19 and by heating the ammonium salt of phenyl-acetic acid.20... [Pg.94]

Poly(4-vinylpyridine) resins 6 cross-linked with 9.6 % divinylbenzene and 68-82 % alkylated also have been tested as catalysts for reaction of 1-bromooctane with cyanide ion 81). The catalytic activities depended on the organic solvent in the order benzene > toluene > o-dichlorobenzene. No swelling data were reported, so it is not known if the activities correlate with the swollen volumes of the catalysts. [Pg.62]

Polymer supports different from polystyrene show different response to % RS in triphase catalysis of nucleophilic displacements. Poly(4-vinylpyridines) 66-71 % alkylated with C8, C12, and C16 chains (6) give high yields of cyanide displacement on 1-bromooctane and on 1-iodooctane and of bromide/iodide exchange of the 1-halooctanes81,87). An 81.6% RS n-butyl-quaternized poly(4-vinylpyridine) (6)... [Pg.70]

The resulting catalyst was highly active for cyanide and acetate ion displacements on 1-bromobutane. As expected, soluble low molecular weight quaternary ammonium salts and a soluble quaternized linear poly(ethyleneimine) were even more active, presumably because they had no mass transfer and intraparticle diffusional limitations. These catalysts had a much higher density of charged sites (at least within the micro domains of the poly(ethyleneimine)) than any of the other active quaternary ammonium ion catalysts reported for nucleophilic displacement reactions. [Pg.71]

Poly(n-alkyl isocyanate) compounds have a rigid helical structure in solution (174). As shown in Scheme 74, a chirally deuterium-labeled isocyanate is polymerized by sodium cyanide to form a product with a very high rotation value (175). The rotation is highly temperature dependent because of the unique chain structure of the product. Interestingly, the reaction of hexyl isocyanate in the presence of 1 mol % of a related chiral analogue leads to a polymer with a high rotation value. The bias of the chain helicity could be induced by living achiral-chiral copolymers. [Pg.101]

In summary, the reaction between an alkali metal alkoxide and a poly-hydroxy compound in hot alcoholic media produces an alcoholate and, possibly, a small proportion of alkoxide adduct however, the conditions governing the ratio of alcoholate to adduct have not yet been well defined. Reactions with alkali metal hydroxides and cyanides produce mixtures (of alcoholate and adduct) that consist mainly of alcoholate. Occurrence of reactions between alkaline-earth metal hydroxides and polyhydroxy compounds in anhydrous alcoholic media has not been reported. [Pg.259]

When H2S is passed into a solution of a tnvalent Rh salt at lCKTC, the hydrosulfide, Rh(SH)3, is formed. This black precipitate is insoluble in (NH4)>S. Rh forms many complexes with NH3, amines, cyanide, chloride, bromide, and numerous polynitrogen and poly oxygen chelating agents. [Pg.1445]


See other pages where POLY-CYANIDES is mentioned: [Pg.192]    [Pg.193]    [Pg.87]    [Pg.192]    [Pg.193]    [Pg.87]    [Pg.259]    [Pg.299]    [Pg.48]    [Pg.362]    [Pg.330]    [Pg.819]    [Pg.115]    [Pg.329]    [Pg.211]    [Pg.665]    [Pg.663]    [Pg.320]    [Pg.828]    [Pg.97]    [Pg.65]    [Pg.533]    [Pg.105]    [Pg.161]    [Pg.160]    [Pg.488]    [Pg.349]    [Pg.174]    [Pg.22]    [Pg.509]    [Pg.299]    [Pg.116]    [Pg.244]   
See also in sourсe #XX -- [ Pg.192 ]




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