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(inorganic chemistry)
A salt or ester of cyanic acid containing the radical CNO.



a salt or ester of cyanic acid. Cyanate salts, unlike cyanic acid, are very stable compounds: for example, sodium cyanate, NaOCN, has a melting point of 550°C, and potassium cyanate, KOCN, decomposes without melting only at 700°C.

The cyanate salts of the alkali metals are soluble in water and insoluble in alcohol and ether. They are produced by the oxidation of the corresponding cyanides by atmospheric oxygen or by the lead oxides PbO or PbO2. They are used in various syntheses, for example, in the production of semicarbazide. Ammonium cyanate, NH4OCN, which was used by F. Wöhler in the first successful synthesis (1828) of an organic compound (urea) from an inorganic compound, may be obtained in an exchange reaction from silver cyanate and ammonium chloride.

Esters of cyanic acid exist in two isomeric forms: ROCN and RNCO. The cyanate esters (ROCN) do not have practical importance, while isocyanates (RNCO) are used in industry for the production of polyurethanes and herbicides. (SeeISOCYANATES.)


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References in periodicals archive ?
Cyanate ester resins have an attractive range of dielectric properties when considered againsi other candidate materials.
Apart from ihe preparation of polycyanurate dielectric thin films with a uniform and defect-free surface, another objective of this work is io investigate whether and how the cyanate ester monomers undergo plasma polymerization.
Rhone-Poulenc uses two hydroxyl-terminated polybutadiene/acrylonitrile oligomers to toughen its AroCy cyanate ester monomers and prepolymers.
Like the rubber-modified resins, a new group of modified aromatic cyanate ester resins from ICI Fiberite, Tempe, Ariz.
The cyanate ester resin l,l'-bis(4-cyanatophenyl) ethane with a cyanate equivalent of 132 g/equiv was obtained from Shanghai Huifeng Technical and Business (Shanghai, China).
Ising, AroCy Cyanate Ester Resins, Hi-Tek Polymers publication (1991).
A number of studies of the thermal and thermo-oxidative stability of aryl dicyanate esters have been presented but it is generally accepted that the decomposition mechanism of polycyanurates proceeds in several stages, involving reaction of unconverted cyanate functionality with air born moisture to form an iminocarbonate intermediate before the rapid rearrangement to a carbamate.
Two other new cyanate esters from Bryte Technologies include EX-1505 and EX-1509, both intended for high-temperature applications.
Cyclotrimerization reaction occurs by the reaction of three cyanate groups opening up and forming a symmetrically substituted triazine ring as shown in the literature, resulting in a fully crosslinked polymer.
1] for the methyl groups in BADCy monomer was taken as an internal reference, cyanate group conversion (X) was obtained by taking the ratio of the cyanate group absorbance at 2270 [cm.
Although a cured cyanate resin has a relatively higher toughness than a cured BMI or a cross-linked epoxy resin, it still requires suitable modification to improve toughness without reducing the intrinsic physical strength for structural applications (9).
In our earlier work, it was found that the toughness of the epoxy matrices was improved by the incorporation of siloxane, cyanate ester, unsaturated polyester, vinyl ester oligomer, and polysulfone into epoxy resin (17-22).