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2-Methyl-2-butene, 2m2b, 2-methylbut-2-ene, beta-isoamylene, or Trimmethylethylene is an alkene hydrocarbon with the molecular formula C 5 H 10.. Used as a free radical scavenger in trichloromethane (chloroform) and dichloromethane (methylene chloride).
In atmospheric chemistry, the most common scavenger is the hydroxyl radical, a short-lived radical produced photolytically in the atmosphere. It is the most important oxidant for carbon monoxide , methane and other hydrocarbons , sulfur dioxide , hydrogen sulfide , and most of other contaminants, removing them from the atmosphere.
In free radical polymerization, radicals formed from the decomposition of an initiator molecule are surrounded by a cage consisting of solvent and/or monomer molecules. [6] Within the cage, the free radicals undergo many collisions leading to their recombination or mutual deactivation. [5] [6] [9] This can be described by the following reaction:
Radical polymerisation of unsaturated monomers is generally propagated by C-radicals. These can be effectively terminated by combining with other radicals to form neutral species and many true inhibitors operate through this mechanism. In the simplest example oxygen can be used as it exists naturally in its triplet state (i.e. it is a diradical).
Living free radical polymerization is a type of living polymerization where the active polymer chain end is a free radical. Several methods exist. Several methods exist. IUPAC recommends [ 1 ] to use the term " reversible-deactivation radical polymerization " instead of "living free radical polymerization", though the two terms are not synonymous.
The alkyl radical formed after hydrogen atom transfer is susceptible to standard radical reactions when scavengers are present in sufficient excess to outcompete the nitrosyl radical. Soon after their initial disclosure, Barton and co-workers reported the trapping of the radical with I 2 and CCl 3 Br (as Iodine and Bromine radical sources ...
Pentaerythritol tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate): A primary antioxidant consisting of sterically hindered phenols with para-propionate groups. Primary antioxidants (also known as chain-breaking antioxidants) act as radical scavengers and remove peroxy radicals (ROO•), as well as to a lesser extent alkoxy radicals (RO•), hydroxyl radicals (HO•) and alkyl radicals (R•).
Galvinoxyl is a commercially available radical scavenger. [1] It finds use both as a probe for studying radical reactions and as an inhibitor of radical polymerization.It may be synthesized by oxidation of the parent phenol with lead dioxide or potassium hexacyanoferrate(III).