Concept explainers
Interpretation:
To give the step by step anionic
Concept introduction:
Poly (ethylene glycol) is a polyether which is obtained from the anionic polymerization of ethylene oxide (C2H4O). The anionic polymerization of ethylene oxide is complicated by the association phenomenon and the participation of ion-pair and free ion intermediates in the propagation reactions.
Anionic polymerization takes place where the monomer unit have a EWG (elctron withdrawing group). This type of polymerization proceeds with the addition of the nucleophile with the monomer’s double bond. The nucleophile may be hydroxide, cyanide etc. On other hand it can also be initiated by the elctron transfer from the alkali species used as an catalyst.
In general there is no termination step. The reaction will continue till all the monomer and the catalyst have been consumed.
Anionic polymerization is also called living polymerization as the reaction will again start when the monomer and catalyst is added to it.
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Organic Chemistry
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- EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENT