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Amino resins chemistry

Amino resin chemistry goes back to the 1880s. The first mention of a urea-formaldehyde reaction product was by Tollens (9) in 1884 in a report of work done by an associate named Holzer. Very few references relating to amino resins can be found in the chemical literature prior to 1900. Ludy (10) in 1889 and Carl Goldschmidt (11) in 1896 mentioned products that were similar to the material... [Pg.1104]

Vale, C. P., and Taylor, W. G. K., Amino Plastics, London, Iliffe Books, Ltd., 1964. A veiy comprehensive review of amino resin chemistry and technology. [Pg.346]

Melamine. Melamine (cyanurotriamide, 2,4,6-ttiainino-j -triazine) C H N, is a white crystalline soHd, melting at approximately 350°C with vaporization, only slightly soluble in water. The commercial product, recrystallized grade, is at least 99% pure. Melamine was synthesized eady in the development of organic chemistry, but it remained of theoretical interest until it was found to be a usehil constituent of amino resins. Melamine was first made commercially from dicyandiamide [461-58-5] (see Cyanamides), but is now made from urea, a much cheaper starting material (9—12) (see also... [Pg.322]

The chemistry of melamine has been reviewed (63,64). Melamine, although moderately basic, is better considered as the triamide of cyanuric acid than as an aromatic amine (see Cyanuric AND ISOCYANURIC AClDs). Its reactivity is poor in nearly all reactions considered typical for amines. In part, this may be a result of its low solubiUty (see Amino resins and plastics). [Pg.372]

Aminoquinolines, 21 185, 199 Amino resins, 16 409. See also Amino resins and plastics coating resins, 7 96-98 formaldehyde in, 12 121 Amino resins and plastics, 2 618-652 chemistry of resin formation,... [Pg.49]

Amino resins. Llrea, the first recorded, synthetically produced, organic compound, can be reacted with formaldehyde to form polymers called urea-formaldehyde resins or amino resins. Its chemistry is similar to the phenolic resins. [Pg.364]

The chemistry of melamines and phenolics is quite similar. In both cases formaldehyde [50-00-0] is added to the reactive sites on the parent ring to form methylol phenols (3) or methylol melamines (4) (see PHENOLRESINS Amino resins). There are six reactive sites on the triazine ring of melamine [108-78-1] (1) so it is possible to form hexa.methylolmelamine. However, the most common degree of methylolation is 1.5—2.0. The ortho and para positions of phenol are active thus phenol can be trimethylolated (2). However, as with melamine, lower degrees of methylolation such as 1.2—2.5 are common. [Pg.531]

Although the chemistry of the reaction of formaldehyde with urea and other amino compounds was investigated much earlier, the first useful product did not come on the market until the 1920s. The first commercial application for amino resins was in molding compounds and utilized a resin made with an equimolar combination of urea and thiourea, the invention of Edmond C. Rossiter ( ). The Beetle brand name was applied to the new molding compound and has remained prominent in amino resins ever since. It is of special interest that the very first commercial product based on amino resins should be a complex formulation such as a molding compound. [Pg.1101]

This, in its very simplest form, is the chemistry of amino coatings. There are, of course, an enormous variety of types and reactivities of both amino compounds and polymers. While it would be useless to try to enumerate the variations possible, some systematization of the reactivity of amino resins is necessary to understand the trends in the coating industry. [Pg.1110]

The wall formation is a chemical and physical process.Under acidic condition, the amino resin prepolymer, which is methylol compound and water soluble, becomes more hydrophobic because of the etherification and methylene bridge formation. The hydrophilic and hydrophobic interactions drive the oligomer concentrated on the interface and create a primary wall on the oil droplet. And finally with the further polycondensation, the wall is cross-linked and the wall thickness is built up. The related chemistry is presented in Equations 16.1 through 16.4. ... [Pg.309]

Pizzi, A., Amino resin wood adhesives (Chapter 2). Wood Adhesives Chemistry and Technology, Vol. 1, Marcel Dekker Div., Taylor Francis, New York,... [Pg.132]

Melamine-Formaldehyde. Melamine-formaldehyde and urea-formaldehyde have similar polymerization chemistry, so they are often referred to as amino resins. However, they differ in properties, apphcations, economics, and market volume, so they are best studied independently. Melamine offers superior resistance to heat, weather, and moisture, but it is more expensive than urea, so it is used only when its superior performance is required. The U.S. market volume is about 350 million Ih/yr. [Pg.141]

A wide range of adhesive types and chemistries are used to bond wood elements to one another (Table 2), but relatively few adhesive types are utilized to form the composites themselves. The vast majority of pressed-wood products use synthetic thermosetting adhesives. In North America the most important wood adhesives are the amino resins (qv), eg, urea-formaldehyde (UF) and melamine-formaldehyde (MF), which account for 60% by volume of adhesives used in wood composite products, followed by the phenolic resins (qv) eg, phenol-formaldehyde (PF) and resorcinol-formaldehyde (RF), which account for 32% of wood composite adhesives (12,13). The remaining 9% consists of cross-linked vinyl (X-PVAc) compounds, thermoplastic poly(vinyl acetates) (PVA), soy-modified casein, and polymeric diphenylmethylene diisocyanate (pMDI). Some products may use various combinations of these adhesives to balance cost with performance. [Pg.9264]

J. F. Blais, Amino Resins, Van Nostrand-Reinhold, Princeton, New Jersey, 1959 B. Bann and S. A. Miller, Chem. Rev. 58, 131 (1958) E. M. Smolin and L. Rapoport, The Chemistry of Heterocyclic Compounds, s-Triazine and Derivatives, Wiley (Interscience), New York, 1959 H. P. Wohnsiedler, Kirk-Othmer Encycl. Chem. Technol. 2nd Ed. 2, 225 (1963). [Pg.45]

This book is a useful guide for the industrial, and academic chemist as well as students studying polymer chemistry which involve ureas, melamines, benzoguanamine/aldehyde resins (amino resins-aminoplasts), phenol/aldehyde condensates, epoxy resins, silicone resins, alkyd resins, polyacetals/polyvinyl acetals, polyvinyl ethers, polyvinylpyrrolidones, polyacrylic acids and polyvinyl chloride. [Pg.433]

Melamine was synthesized early in the history of organic chemistry but remained a chemical curiosity until it was found to react with formaldehyde to form a useful amino resin. Melamine was first manufactured from dicyan-diamide, but it is now made from urea, a much lower-cost starting material. In this process the urea is dehydrated to cyanamid which terminates to melamine. The reaction is carried out at high pressure in the presence of ammonia to suppress the formation of deamination products. Ammonium carbamate is also formed in the reaction and must be recycled to convert it back to urea. [Pg.343]


See other pages where Amino resins chemistry is mentioned: [Pg.321]    [Pg.329]    [Pg.322]    [Pg.267]    [Pg.168]    [Pg.175]    [Pg.1101]    [Pg.1109]    [Pg.1109]    [Pg.636]    [Pg.321]    [Pg.329]    [Pg.455]    [Pg.471]    [Pg.1354]    [Pg.4434]    [Pg.5580]    [Pg.6427]    [Pg.189]    [Pg.909]    [Pg.74]    [Pg.914]    [Pg.926]    [Pg.929]    [Pg.149]    [Pg.232]    [Pg.76]    [Pg.73]    [Pg.511]   


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