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Toluene is widely used in the paint, dye, rubber, chemical, glue, printing, and pharmaceutical industries as a solvent. [38] Nail polish, paintbrush cleaners, and stain removers may contain toluene. Manufacturing of explosives (TNT) uses it as well. Toluene is also found in cigarette smoke and car exhaust.
BHT is used as a preservative ingredient in some foods. With this usage BHT maintains freshness or prevents spoilage; it may be used to decrease the rate at which the texture, color, or flavor of food changes. [25] Some food companies have voluntarily eliminated BHT from their products or have announced that they were going to phase it out. [26]
Using these models they can measure and test for generalized patterns in the structure of real food web networks. Ecologists have identified non-random properties in the topological structure of food webs. Published examples that are used in meta analysis are of variable quality with omissions.
The simplest member, toluene (or methylbenzene), has the hydrogen atom of the benzene ring replaced by a methyl group. The chemical formula of alkylbenzenes is C n H 2n-6. [2] Safety hazards of toluene. Oftentimes, toluene is used as an organic solvent.
It is derivative of styrene and is used as a comonomer in the production of specialized polystyrenes. It is produced by the dehydrogenation of 4-ethyltoluene . [ 1 ] It is also sometimes used in the production of styrene-free Polyester resin .
Purification is challenging because the individual isomers have similar properties. The 2,6 and 3,5 isomers do not form acceptably from toluene or chlorotoluenes, so these isomers are prepared by indirect methods. For example, 2,6-dichlorotoluene can be prepared by chlorination of 4-toluenesulfonyl chloride followed by desulfonation. [1]
A laboratory route to o- and p-iodotoluene proceeds from toluene, which is treated with a mixture of iodine and nitric acid in an electrophilic aromatic substitution.The resulting mixture of o and p-iodotoluene is then separated by fractional freezing; cooling the mixture in an ice bath results in solidification of p-iodotoluene, which can then be isolated by filtration, while the o ...
TsOH is most often supplied as the monohydrate, and it may be necessary to remove the complexed water before use. Impurities can be removed by recrystallization from its concentrated aqueous solution followed by azeotropic drying with toluene. [2] TsOH finds use in organic synthesis as an "organic-soluble" strong acid. Examples of uses include: