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Para tertiary butylphenol formaldehyde resin, also known as p-tert-butylphenol-formaldehyde resin (PTBP-FR), is a thermoplastic phenol-formaldehyde resin found in commercial adhesives, particularly glues used to bond leather and rubber. It has broad usage in a large variety of industries and can be found in many household textile products and ...
Novolaks (or novolacs) are phenol-formaldehyde resins with a formaldehyde to phenol molar ratio of less than one. In place of phenol itself, they are often produced from cresols (methylphenols). The polymerization is brought to completion using acid-catalysis such as sulfuric acid, oxalic acid, hydrochloric acid and rarely, sulfonic acids. [4]
Phenol-formaldehyde resins (PF) were the first commercially relevant impregnation resins, made by reacting phenol and formaldehyde, creating a polymer network inside of the wood upon curing. [7] Phenol can react with formaldehyde at the ortho and para positions, generating mono, di, and trimethylolphenol as the reaction products. [6]
A common method for hydroxymethylation involves the reaction of formaldehyde with active C-H and N-H bonds: R 3 C-H + CH 2 O → R 3 C-CH 2 OH R 2 N-H + CH 2 O → R 2 N-CH 2 OH. A typical active C-H bond is provided by a terminal acetylene [1] or the alpha protons of an aldehyde. [2]
A melamine-resin plate A melamine-resin ladle. Melamine resin is often used in kitchen utensils and plates (such as Melmac). Because of its high dielectric constant ranging from 7.2 to 8.4, melamine resin utensils and bowls are not microwave safe. [3] During the late 1950s and 1960s melamine tableware became fashionable.
Salicyl alcohol is produced by the hydroxymethylation of phenol using formaldehyde: [4] C 6 H 5 OH + CH 2 O → C 6 H 4 OH(CH 2 OH. Air oxidation of salicyl alcohol gives salicylaldehyde. C 6 H 4 OH(CH 2 OH + O → C 6 H 4 OH(CHO) +H 2 O. Chemical sweeteners are formed by acetal formation with e.g. isovanillin (Cmp4). [5]
This makes the hydroxymethyl group an alcohol. It has the identical chemical formula with the methoxy group (−O−CH 3) that differs only in the attachment site and orientation to the rest of the molecule. However, their chemical properties are different. [1] [2] Hydroxymethyl is the side chain of encoded amino acid serine. [3]