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Phenol is so inexpensive that it also attracts many small-scale uses. It is a component of industrial paint strippers used in the aviation industry for the removal of epoxy, polyurethane and other chemically resistant coatings. [33] Due to safety concerns, phenol is banned from use in cosmetic products in the European Union [34] [35] and Canada ...
In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. [1] [2] [3] Phenolic compounds are produced by plants and microorganisms. [4] Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. [5]
The simplest is phenol, C 6 H 5 OH. Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule. Phenol – the simplest of the phenols Chemical structure of salicylic acid, the active metabolite of aspirin. Phenols are both synthesized industrially and produced by plants and ...
Phenol-formaldehyde resins, as a group, are formed by a step-growth polymerization reaction that can be either acid- or base-catalysed.Since formaldehyde exists predominantly in solution as a dynamic equilibrium of methylene glycol oligomers, the concentration of the reactive form of formaldehyde depends on temperature and pH.
These compounds are also used as building-block chemicals in making fragrances, thermoplastic elastomers, antioxidants, oil field chemicals, and fire retardant materials. As plastizers and antioxidants, alkylphenols are also found in tires, adhesives, coatings, carbonless copy paper and high performance rubber products.
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The term polyphenol is not well-defined, but it is generally agreed that they are natural products with "several hydroxyl groups on aromatic rings" including four principal classes: "phenolic acids, flavonoids, stilbenes, and lignans". [5] Flavonoids include flavones, flavonols, flavanols, flavanones, isoflavones, proanthocyanidins, and ...
The United States Patent and Trademark Office granted Baekeland a patent for a "Method of making insoluble products of phenol and formaldehyde" on December 7, 1909. [12] Producing hard, compact, insoluble, and infusible condensation products of phenols and formaldehyde marked the beginning of the modern plastics industry .