Melamine plastics

Urea is also used as feed supplement for mminants, where it assists in the utilization of protein. Urea is one of the raw materials for urea—formaldehyde resins. Urea (with ammonia) pyrolyzes at high temperature and pressure to form melamine plastics (see also Cyanamides). Urea is used in the preparation of lysine, an amino acid widely used in poultry feed (see Amino acids Feeds and feed additives, petfoods). It also is used in some pesticides. 

Production of decorated melamine plastic dinner plates makes use of molding and laminating techniques. The pattern is ptinted on the same type of paper used for the protective overlay of decorative lamiaates, treated with melamine resia and dried, and then cut iato disks of the appropriate size. 

Melamine plastics Group of plastics whose resins are formed by the condensation of melamine and aldehydes. 

CaNCN is used as a direct application fertilizer, weed killer, and cotton defoliant it is also used for producing cyanamide, dicyandiamide and melamine plastics. Production formerly exceeded 1.3 million tonnes pa, but this has fallen considerably in the last few years, particularly in the USA where the use of CaNCN as a nitrogenous fertilizer has been replaced by other materials. In 1990 most of the world s supply was made in Japan, Gennany and Canada. 

The enforcement in Denmark of EU Directives on food packaging materials is discussed. Enforcement activities considered include studies of total migration from food contact materials, migration from kitchen-and tableware made of melamine plastics and migration of di(2-ethylhexyl)adipate from plasticised PVC films. Activities which need to be undertaken to increase the effectiveness of enforcement activities in the field of migration are described, including development of selfinspection programmes in industry, European network of enforcement, more rapid analysis and provision of information to the consumer. 2 refs. 

Which of the following could be a nonpetrochemical plastic (a) Bakelite (b) urea plastics or (c) melamine plastics ... 

Cellulose, which is more fibrous than wood flour, is used as a filler for urea and melamine plastics. Melamine dishware is a laminated structure consisting of molded resin-impregnated paper. Starch and soybean derivatives are biodegradable, and the rate of disintegration of resin composites containing these fillers may be controlled by the amount of these fillers present in polymers. 

In spite of Baekeland s success, it was another two decades before the Age of Polymers can really be said to have been born. The 1920s and 1930s saw the invention and/or commercialization of a number of new polymeric products ("plastics") that most consumers now consider to he essential chemicals in their lives. These products include the urea formaldehyde plastics (1923), polyvinyl chloride (PVC 1926), polystyrene (1929), nylon (1930), polymethylmethacrylate (acrylics 1931), polyethylene (1933), the melamine plastics (1933), polyvinylidene chloride (Saran 1933), polyvinyl acetate (PVA 1937), and tetrafluoroethylene (Teflon 1938). 

Calcium cyanamide (CaNCN) is used as a direct-application fertilizer, weed killer, and cotton defoliant. It is also used to make cyanamide, dicyandiamide, and melamine plastics ... 

Note As this table shows, the largest outlet for amino resins by far is their use as adhesives or binders for reconstituted wood products made from sawdust and wood chips. Urea-formaldehyde resin is most commonly used. Melamine-formaldehyde resin can provide improved water resistance and may be combined with the urea resin to provide an improved product. Molding compounds are about the next most important outlet for amino resins. It is approximately evenly divided between urea and melamine. The primary use for urea moldings is in the electrical field, while the most important area for molded melamine plastic is dinnerware. 

Chem. Descrip. Zinc stearate CAS 557-05-1 EINECS/ELINCS 209-151-9 Uses Lubricant for urea/formaldehyde, melamine plastics antitackiTrer, dusting agent, and lubricant for surfs, of uncured rubber slabs flatting agent for solvent-based paints... 

Melamine plastics. Together with urea plastics, these are the most important representatives of the amino plastics. Their properties (water and chemical resistance, thermal stability) are superior to those of urea plastics. 

Urea plastics. One of the most important representatives of amino plastics, besides the melamine plastics. 

Urea is used as a cattle feed supplement where it is a cheap source of protein. It is used both in prill form (microprill at 0,2/0.4 mm diameter) and as a liquid in a mixture of urea ( 75% solution), molasses, and phosphoric acid. It is the feed material for melamine plastic and for various glues. The glues are either urea-formaldehyde or urea-melamine-formaldehyde. TTie latter is waterproof and is used for marine plywood. 

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