Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton. Like cyanamide, it contains 66% nitrogen by mass and, if mixed with resins, has fire retardant properties due to its release of nitrogen gas when burned or charred, and has several other industrial uses. Melamine is also a metabolite of cyromazine, a pesticide. It is formed in the body of mammals who have ingested cyromazine. It has been reported that cyromazine can also be converted to melamine in plants. Melamine is combined with formaldehyde to produce melamine resin, a very durable thermosetting plastic used in Formica, and melamine foam, a polymeric cleaning product. The end products include countertops, dry erase boards, fabrics, glues, housewares, dinnerware, cooking spoons, guitar saddles, guitar nuts, acoustic foam paneling, and flame retardants. Melamine is one of the major components in Pigment Yellow 150, a colorant in inks and plastics. Melamine is sometimes illegally added to food products in order to increase the apparent protein content. Standard tests, such as the Kjeldahl and Dumas tests, estimate protein levels by measuring the nitrogen content, so they can be misled by adding nitrogen-rich compounds such as melamine.There is an instrument (SPRINT) developed by the company CEM Corp that allows the determination of protein content directly in some applications; this cannot be fooled by adding melamine in the sample. Ultrasound-assisted extractive electrospray ionization mass spectrometry (EESI-MS) has been developed at ETH Zurich (Switzerland) by Zhu et al., (2008) for a rapid detection of melamine in untreated food samples. Ultrasounds are used to nebulize the melamine-containing liquids into a fine spray. The spray is then ionised by extractive electrospray ionisation (EESI) and analysed using tandem mass spectrometry (MS/MS). An analysis requires 30 seconds per sample. The limit of detection of melamine is a few nanograms of melamine per gram of milk. Crystallization and washing of melamine generates a considerable amount of waste water, which is a pollutant if discharged directly into the environment. The waste water may be concentrated into a solid (1.5-5% of the weight) for easier disposal. The solid may contain approximately 70% melamine, 23% oxytriazines (ammeline, ammelide, and cyanuric acid), 0.7% polycondensates (melem, melam, and melon). In the Eurotecnica process, however, there is no solid waste and the contaminants are decomposed to ammonia and carbon dioxide and sent as off gas to the upstream urea plant; accordingly, the waste water can be recycled to the melamine plant itself or used as clean cooling water make-up. Melamine also enters the fabrication of melamine poly-sulfonate used as superplasticizer for making high-resistance concrete. Sulfonated melamine formaldehyde (SMF) is a polymer used as cement admixture to reduce the water content in concrete while increasing the fluidity and the workability of the mix during its handling and pouring. It results in concrete with a lower porosity and a higher mechanical strength, exhibiting an improved resistance to aggressive environments and a longer life-time.
Belongs to the class of organic compounds known as 1,3,5-triazines. 1,3,5-Triazines are compounds containing a triazine ring, which is a heterocyclic ring, similar to the six-member benzene ring but with three carbons replaced by nitrogen atoms, at ring positions 1, 3, and 5.
