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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.
Urea plant using ammonium carbamate briquettes, Fixed Nitrogen Research Laboratory, ca. 1930 Carl Bosch, 1927. The Bosch–Meiser process is an industrial process, which was patented in 1922 [1] and named after its discoverers, the German chemists Carl Bosch and Wilhelm Meiser [2] for the large-scale manufacturing of urea, a valuable nitrogenous chemical.
Two steps in formation of urea-formaldehyde resin, which is widely used in the production of particle board When condensed with phenol , urea , or melamine , formaldehyde produces, respectively, hard thermoset phenol formaldehyde resin, urea formaldehyde resin, and melamine resin.
The compound is formed by the condensation of formaldehyde with urea. Methylene diurea is the substrate for the enzyme methylenediurea deaminase . Applications
In situ polymerization of such formaldehyde systems usually involves the emulsification of an oil-phase in water. Then, water-soluble urea/melamine formaldehyde resin monomers are added, which are allowed to disperse. The initiation step occurs when acid is added to lower the pH of the mixture.
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.
DMTU is an intermediate in the production of urea-formaldehyde resins. [ 1 ] Together with methylene diurea , DMTU is a component of some controlled-release fertilizers .
This pattern is illustrated by the use of formaldehyde in the production various polymers and resins from phenol-formaldehyde condensations (Bakelite, Novolak, and calixarenes). Similar crosslinking occurs in urea-formaldehyde resins. The hydroxymethylation of N-H and P-H bonds can often be reversed by base.