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Urea-formaldehyde (UF), also known as urea-methanal, so named for its common synthesis pathway and overall structure, [1] is a nontransparent thermosetting resin or polymer. It is produced from urea and formaldehyde. These resins are used in adhesives, plywood, particle board, medium-density fibreboard (MDF), and molded objects.
Putrefying bacteria use amino acids or urea as an energy source to decompose dead organisms. In the process, they produce ammonium ions. Nitrifying bacteria then convert this ammonium into nitrate by oxidation, which can then be used by plants to create more proteins thus completing the nitrogen cycle. [6] This process is called nitrification.
Formaldehyde is a common precursor to more complex compounds and materials. In approximate order of decreasing consumption, products generated from formaldehyde include urea formaldehyde resin, melamine resin, phenol formaldehyde resin, polyoxymethylene plastics, 1,4-butanediol, and methylene diphenyl diisocyanate. [40]
The Biden administration has officially determined the chemical formaldehyde poses an “unreasonable” risk to human health and should be regulated. The Environmental Protection Agency (EPA ...
To the average consumer, formaldehyde may be best known as an embalming agent. But this naturally occurring chemical is a major industrial staple, used in many consumer goods, including cleaning ...
Despite genuine concerns, formaldehyde is a naturally occurring substance, of which human beings produce approximately 1.5 oz a day as a normal part of a healthy metabolism. Formaldehyde also occurs naturally in many fruits, such as bananas, apples, and carrots, and does not bioaccumulate in either plants or animals.
Formaldehyde is dangerous to human health. [8] [9] In 2011, the US National Toxicology Program described formaldehyde as "known to be a human carcinogen". [10] [11] [12] The danger of formaldehyde is a major reason for the development of formaldehyde releasers which release formaldehyde slowly at lower levels. [13]
The basic reaction of urea and formaldehyde to create a urea-formaldehyde resin, followed by the condensation [12] Urea-formaldehyde resins (UF) are a class of impregnation resins for wood modification made by reacting urea with formaldehyde. This resin can be polymerized after impregnation into the wood substrate by oven-curing.