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The Wikipedia page says this:

Ethoxylation is an industrial process in which ethylene oxide is added to alcohols and phenols to turn it into a surfactant.

How does the reaction proceed?

The answer to the question "Do epoxide rings react with bases?" regarding epoxide rings reacting with bases does not include alcohols, and does not answer my question.

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    $\begingroup$ Does this answer your question? $\endgroup$
    – Klaus-Dieter Warzecha
    May 4, 2015 at 9:34
  • $\begingroup$ @KlausWarzecha Maybe that reaction might be one of the reaction steps. I don't know. $\endgroup$
    – Larry
    May 4, 2015 at 10:02
  • $\begingroup$ @Martin So intead of CH3O- of that answer, lp of CH3OH will attack? And Eka gave me a link - chemstations.com/content/documents/technical_articles/ethox.pdf and it is different. $\endgroup$
    – Larry
    May 4, 2015 at 16:44
  • $\begingroup$ The link you provided has does not explain anything about the mechanism and it is about a base catalysed reaction. $\endgroup$
    – Martin - マーチン ♦
    May 5, 2015 at 8:51
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    $\begingroup$ @Larry The alcoholate, because it is deprotonated, has three lone pairs, one of them, the HOMO, will attack in a nucleophilic manner. An alcohol still has two lone pairs, and one of the is the HOMO, which will make the nucleophilic attack. The whole process might be slower, as it is less nucleophilic, but you can assume the mechanism to be almost identical. $\endgroup$
    – Martin - マーチン ♦
    May 15, 2015 at 3:21

1 Answer 1

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Because of its special chemical struture Ethyelene oxide (EO) is highly reactive material thus easily participate in chemical reactions which includes polymerization. Mechanism of opening of EO's ring in acidic and alkaline medium is given below

enter image description here

If you see in both cases a molecule with alcoholic group ($\ce{-OH}$) is formed.If the epoxyethane is in excess, the reaction can continue and could lead to polymerization.

A good example is the reaction between EO and water

enter image description here

As explained in wikipedia ethoxylation is an industrial process to make surfactant from EO. Surfactants are chemical molecule which contain both hydrophobic groups (their tails) and hydrophilic groups (their heads).

The end result of reaction with EO and alchol is a long chain molecule with these hydrophobic ($\ce{-R}$) and hydrophilic ($\ce{-OH}$) group

enter image description here

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  • $\begingroup$ In the first image, from where did the H+ and OH- come from? Where did they alcohol go. $\endgroup$
    – Larry
    May 4, 2015 at 11:01
  • $\begingroup$ It just shows reaction environment H+ from acid (HCl, H2SO4..etc) and OH- from base (NaOH etc) see this link $\endgroup$
    – Eka
    May 4, 2015 at 11:14
  • $\begingroup$ Where did the alcohol go? $\endgroup$
    – Larry
    May 4, 2015 at 13:26
  • $\begingroup$ @larry See the alcohol reaction here R-OH is the alcohol see this example $\endgroup$
    – Eka
    May 4, 2015 at 13:49
  • $\begingroup$ But that has an acid and alcohol. Epoxide and alcohol? $\endgroup$
    – Larry
    May 4, 2015 at 13:54

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