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  2. Urea-formaldehyde - Wikipedia

    en.wikipedia.org/wiki/Urea-formaldehyde

    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.

  3. Urea - Wikipedia

    en.wikipedia.org/wiki/Urea

    The structure of the molecule of urea is O=C(−NH 2) 2.The urea molecule is planar when in a solid crystal because of sp 2 hybridization of the N orbitals. [8] [9] It is non-planar with C 2 symmetry when in the gas phase [10] or in aqueous solution, [9] with C–N–H and H–N–H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.

  4. Formaldehyde - Wikipedia

    en.wikipedia.org/wiki/Formaldehyde

    Formaldehyde (/ f ɔːr ˈ m æ l d ɪ h aɪ d / ⓘ for-MAL-di-hide, US also / f ə r-/ ⓘ fər-) (systematic name methanal) is an organic compound with the chemical formula CH 2 O and structure H−CHO, more precisely H 2 C=O. The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde.

  5. Aldehyde - Wikipedia

    en.wikipedia.org/wiki/Aldehyde

    Aldehyde structure. In organic chemistry, an aldehyde (/ ˈ æ l d ɪ h aɪ d /) is an organic compound containing a functional group with the structure R−CH=O. [1] The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group.

  6. Paraformaldehyde - Wikipedia

    en.wikipedia.org/wiki/Paraformaldehyde

    Paraformaldehyde can be depolymerized to formaldehyde gas by dry heating [2] and to formaldehyde solution by water in the presence of a base, an acid or heat. The high purity formaldehyde solutions obtained in this way are used as a fixative for microscopy and histology. The resulting formaldehyde gas from dry heating paraformaldehyde is flammable.

  7. Bakelite - Wikipedia

    en.wikipedia.org/wiki/Bakelite

    These included other types of cast phenolic resins similar to Catalin, and urea-formaldehyde resins, which could be made in brighter colors than poly­oxy­benzyl­methylene­glycol­anhydride. [4] [9] Once Baekeland's heat and pressure patents expired in 1927, Bakelite Corporation faced serious competition from other companies.

  8. Impregnation resin - Wikipedia

    en.wikipedia.org/wiki/Impregnation_resin

    Adding urea to MF resins has been shown to lower the amount of free formaldehyde below the legal limit and is often used for this purpose. [1] Another complication with MF resins is the low solubility of melamine in water. [16] Because of this and the free formaldehyde content, MF resins are not used as commonly in the field of wood modification.

  9. Medium-density fibreboard - Wikipedia

    en.wikipedia.org/wiki/Medium-density_fibreboard

    MDF is typically made up of 82% wood fibre, 9% urea-formaldehyde resin glue, 8% water, and 1% paraffin wax. [4] The density is typically between 500 and 1,000 kg/m 3 (31 and 62 lb/cu ft). [ 5 ] The range of density and classification as light-, standard-, or high-density board is a misnomer and confusing.