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22-405: Melmac is: A brand name of dinnerware molded from Melamine resin , made by American Cyanamid , most popular in the 1940s through the 1960s. The fictional planet and homeworld to the alien life form in the eponymously titled sitcom ALF (TV series) (see also New Melmac ) A Staten Island , NY based ska band from the late 1990s. SKV Melmac,

44-413: A limited degree to give resins. Either the melamine-formaldehyde resins or melamine-formaldehyde "monomer" can be cured by treatment with any of several polyols . The principal use of melamine resin is as the main constituent of high-pressure laminates , such as Formica and Arborite , and of laminate flooring . Melamine-resin tile wall panels can also be used as whiteboards . Melamine formaldehyde

66-525: A precursor or a component of bleaches , disinfectants, and herbicides . In 1997, worldwide production was 160 000 tonnes . Cyanuric acid can be viewed as the cyclic trimer of the elusive chemical species cyanic acid , HOCN. The ring can readily interconvert between several structures via lactam-lactim tautomerism . Although the triol tautomer may have aromatic character, the keto form predominates in solution. The hydroxyl (-OH) groups assume phenolic character. Deprotonation with base affords

88-459: A series of cyanurate salts : Cyanuric acid is noted for its strong interaction with melamine , forming insoluble melamine cyanurate . This interaction locks the cyanuric acid into the tri-keto tautomer . Melamine cyanurate is cited as an example of supramolecular chemistry . Cyanuric acid (CYA) was first synthesized by Friedrich Wöhler in 1829 by the thermal decomposition of urea and uric acid . The current industrial route to CYA entails

110-509: A university korfball club from Tilburg, Netherlands, re-established in 2005 An acronym for the Maine Educational Loan Marketing Corporation A variety of Psilocybe cubensis mushrooms. Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Melmac . If an internal link led you here, you may wish to change the link to point directly to

132-446: Is 7700 mg/kg in rats. However, when cyanuric acid is present together with melamine (which by itself is another low-toxicity substance), it will form an insoluble and rather nephrotoxic complex, as evidenced in dogs and cats during the 2007 pet food contamination and in children during the 2008 Chinese milk scandal cases. An impure copper salt of the acid, with the formula Cu(C 3 N 3 O 3 H 2 ) 2 (NH 3 ) 2 ,

154-457: Is commonly done with a turbidometric test , which uses a reagent, melamine, to precipitate the cyanuric acid. The relative turbidity of the reacted sample quantifies the CYA concentration. Referenced in 1957, this test works because melamine combines with the cyanuric acid in the water to form a fine, insoluble, white precipitate ( melamine cyanurate ) that causes the water to cloud in proportion to

176-399: Is heated to the "boil" and treated with a stoichiometric amount of melamine, by which means the cyanuric acid present precipitates as melamine-cyanuric acid complex . The various waste streams containing cyanuric acid and amino -substituted triazines may be combined for disposal, and during upset conditions undissolved cyanuric acid may be present in the waste streams . Intermediates in

198-493: Is implicated in connection to the 2007 pet food recalls , the contamination and wide recall of many brands of cat and dog foods beginning in March 2007. Research has found evidence that cyanuric acid, a constituent of urine, together with melamine forms poorly soluble crystals which can cause kidney failure (see Analysis section above). Cyanuric acid is classified as "essentially nontoxic". The 50% oral median lethal dose ( LD 50 )

220-460: Is mainly used as a precursor to N -chlorinated cyanurates, which are used to disinfect water. The dichloro derivative is prepared by direct chlorination: This species is typically converted to its sodium salt, sodium dichloro-s-triazinetrione . Further chlorination gives trichloroisocyanuric acid , [C(O)NCl] 3 . These N -chloro compounds serve as disinfectants and algicides for swimming pool water. The aforementioned equilibrium stabilizes

242-402: Is often used to saturate decorative paper that is laminated under heat and pressure and then pasted onto particle board ; the resulting panel, often called melamine , is commonly used in ready-to-assemble furniture and kitchen cabinets . Melamine is available in diverse sizes and thicknesses, as well as a large number of colors and patterns. The sheets are heavy for their size, and the resin

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264-578: Is prone to chipping when being cut with conventional table saws. Melamine, with the addition of formaldehyde, cyanuric acid , and DETA ( diethylenetriamine ) has been demonstrated to bind CO 2 for purposes of carbon capture , according to researchers at Stanford , Berkeley , and Texas A&M . Melamine-based resin (e.g., melamine-formaldehyde or melamine-urea-formaldehyde resins) can also be used to microencapsulate active agents, such as healing agents or phase change materials , to prevent leakage above their melting temperature. The resulting surface

286-505: Is quite inert and can hardly be modified with traditional techniques such as silanization . Some research has shown that polydopamine can be effective as a surface modifier for this resin. Melamine-formaldehyde resin forms via the condensation of formaldehyde with melamine to give, under idealized conditions, the hexa-hydroxymethyl derivative. Upon heating in the presence of acid, this or similar hydroxymethylated species undergoes further condensation and crosslinking. Linkages between

308-455: Is used in plastic laminate and overlay materials. Formaldehyde is more tightly bound in melamine-formaldehyde than it is in urea-formaldehyde, reducing emissions. Melamine resin is often used in kitchen utensils and plates (such as Melmac). Because of its high dielectric constant ranging from 7.2 to 8.4, melamine resin utensils and bowls are not microwave safe . During the late 1950s and 1960s melamine tableware became fashionable. Aided by

330-502: The thermal decomposition of urea, with release of ammonia . The conversion commences at approximately 175 °C: CYA crystallizes from water as the dihydrate. Cyanuric acid can be produced by hydrolysis of crude or waste melamine followed by crystallization . Acid waste streams from plants producing these materials contain cyanuric acid and on occasion, dissolved amino-substituted triazines, namely, ammeline , ammelide , and melamine. In one method, an ammonium sulfate solution

352-476: The amount of cyanuric acid in it. More recently, a sensitive method has been developed for analysis of cyanuric acid in urine . FDA permits a certain amount of cyanuric acid to be present in some non-protein nitrogen (NPN) additives used in animal feed and drinking water . Cyanuric acid has been used as NPN. For example, Archer Daniels Midland manufactures an NPN supplement for cattle, which contains biuret, triuret, cyanuric acid and urea . Cyanuric acid

374-486: The chlorine in the pool and prevents the chlorine from being quickly consumed by sunlight . Because of its trifunctionality, CYA is a precursor to crosslinking agents , especially for polyurethane resins and polyisocyanurate thermoset plastics . The experimental antineoplastic drug teroxirone (triglycidyl isocyanurate) is formed by reacting cyanuric acid with 3 equivalents of epichlorohydrin . It works by cross-linking DNA. Testing for cyanuric acid concentration

396-504: The dehydration include both isocyanic acid , biuret , and triuret : As temperature exceeds 190 °C, other reactions begin to dominate the process. The first appearance of ammeline occurs prior to 225 °C and is suspected also to occur from decomposition of biuret but is produced at a lower rate than that of CYA or ammelide. Melamine, [C(NH 2 )N] 3 , formation occurs between 325–350 °C and only in very small quantities. N-substituted isocyanurates can be synthesised by

418-536: The heterocycles include mono-, di-, and poly ethers . The microstructure of the material can be analyzed by NMR spectroscopy. The crosslinking density of melamine resins can be controlled by co-condensation with bifunctional analogues of melamine, benzoguanamine and acetoguanamine . Cyanuric acid Cyanuric acid or 1,3,5-triazine-2,4,6-triol is a chemical compound with the formula (CNOH) 3 . Like many industrially useful chemicals, this triazine has many synonyms. This white, odorless solid finds use as

440-526: The intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Melmac&oldid=1066577808 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Melamine resin Melamine-formaldehyde can be cured by heating, which induces dehydration and crosslinking. The crosslinking can be carried out to

462-542: The stylish modern designs of A. H. Woodfull and the Product Design Unit of British Industrial Plastics, it was thought to threaten the dominant position of ceramics in the market. In the late 1960s the tendency of melamine cups and plates to become stained and scratched led to a decline in sales, and eventually the material became largely restricted to the camping and nursery markets, in which its light weight and resistance to breaking were valued. Melamine resin

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484-411: The trimerisation of isocyanates . This is utilised industrially in the formation of polyisocyanurates . Cyanuric acid is used as a chlorine stabilizer / buffer in swimming pools . It binds to free chlorine and releases it slowly, extending the time needed to deplete each dose of sanitizer . A chemical equilibrium exists between the acid with free chlorine and its chlorinated form. Cyanuric acid

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