Melamine-formaldehyde Formica

Melamine-formaldehyde Formica laminated surfaces Scratch-resistant and hard... 

Plastic laminated sheets produced in 1913 led to the formation of the Formica Products Company and the commercial introduction, in 1931, of decorative laminates consisting of a urea—formaldehyde surface on an unrefined (kraft) paper core impregnated with phenoHc resin and compressed and heated between poHshed steel platens (8,10). The decorative surface laminates are usually about 1.6 mm thick and bonded to wood (a natural composite), plywood (another laminate), or particle board (a particulate composite). Since 1937, the surface layer of most decorative laminates has been fabricated with melamine—formaldehyde, which can be prepared with mineral fiUers, thus offering improved heat and moisture resistance and allowing a wide range of decorative effects (10,11). 

Urea is used as a solid fertilizer, a liquid fertilizer and miscellaneous applications such as animal feed, urea, formaldehyde resins, melamine, and adhesives. Presently, the most popular nitrogen fertilizer is a urea-ammonium nitrate solution. Urea-formaldehyde resins have large use as a plywood adhesive. Melamine-formaldehyde resins are used as dinnerware and for extra-hard surfaces (Formica ). The melamine is synthesized by condensation of urea molecules. 

These resins are used to make unbreakable plastic plates and for the famous kitchen surface Formica . Partly polymerized melamine-formaldehyde mixtures are layered with other polymers such as cellulose (Chapter 49) and phenol-formaldehyde resins and the polymerization is completed under pressure with heat, The result is the familiar, tough, heat-resistant surface. 

Melamine is a compound used to make the melamine-formaldehyde resins in very hard surface materials such as Formica . It is 28.57% carbon, 4.80% hydrogen, and 66.63% nitrogen and has a molecular mass of 126.121. What is melamine s molecular formula ... 

The first commercially successful synthetic polymer was phenol-formaldehyde (PF) [Smith, 1899]. The resin was introduced in 1909 by Baekeland as Bakelite . The urea-formaldehyde resins (UF), were discovered in 1884, but production of Beetle moldable resin commenced in 1928. Three years later, Formica , phenolic paper covered with decorative layer protected by UF, was introduced. The thiourea-formaldehyde molding powders were commercialized in 1920, while in 1935, Ciba introduced Cibanite , anihne-formaldehyde (AF) molding materials, then two years later, the melamine-formaldehyde (MF). 

Formica f6r- ml-k9, f9r-. A trademark of the Formica Corporation for high-pressure, decorative laminates of melamine-formaldehyde, phenolic and other thermosetting... 

Melamine-formaldehyde resin provides both adhesive and functional properties in Formica decorative laminates. To prepare a decorative laminate, a melamine resin-impregnated decorative sheet is sandwiched between a melamine resin-treated protective overlay layer and a number of phenolic resin-treated support layers. The resulting combination provides the remarkable properties of the decorative appearance of the printed pattern protected by the hard, stain-resistant, and abrasion resistant surface provided by the melamine-formaldehyde resin. 

Phenolic and other formaldehyde condensation polymers are also important reactive adhesives. Powdered phenolic resin is mixed with abrasive grains and the mixture is compression molded to form grinding wheels. A B-stage phenolic (Chapter XX) in a solvent is used to impregnate tissue paper. The solvent is evaporated, and the dry sheets are placed between layers of wood in a heated press, where the resin first melts and then cures, bonding the wood to form plywood. Similarly, sheets of paper impregnated with a B-stage melamine-formaldehyde resin are laminated and cured to form the familiar Formica counter tops. 

These phenol/formaldehyde plastics are still around due to their cheapness and good electrical and mechanical properties. They have been joined over the years by other similar materials of which urea/formaldehyde and melamine-formaldehyde must be the best known. The former, for instance, may be seen in the white or light coloured electrical switches and fittings, the latter as hard plastic tableware and decorative laminates of the Formica type. There is little difference in the bonding behaviour of the members of this group. 

A widely used polymeric resin for making construction laminates (Formica), low-cost dinnerware, and so on, is melamine (C3N6H6) formaldehyde. It is harder than phenol formaldehyde. 

Melamine is polymerized with formaldehyde to make formica. Draw a mechanism for the first step in this process. 

Melamine condenses with formaldehyde to give a widely used plastic with good heat resistauce, most familiar iu lamiuates for kitchen worktops and as housewares, and known as Formica. 

Melamine is a strong organic base, which is used primarily to produce melamine resin, which when combined with formaldehyde produces a very durable thermoset plastic. This plastic is often used in kitchen utensils or plates (often sold under the brand name Melmac), and is the main constituent of Formica and Arborite . Melamine tile wall panels are known as whiteboards. Melamine is also used to make decorative wall panels and is often used as a laminate. Melamine is produced from urea, mainly by either of two methods catalyzed gas-phase production or high-pressure liquid-phase production. 

Similar cross-linked macromolecules can be prepared by reaction of formaldehyde with urea (UF), and by melamine (MF) with formaldehyde. These are hard but tough materials which are much less coloured than PF. They are the materials used in white electrical plugs and in pigmented form as Formica for working surfaces. 

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