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Ethylene Glycol Layer?

  1. Sep 29, 2010 #1
    Hi

    I am doing an experiment right now trying to make a mould out of a poly methyl methacrylate (PMMA) using a resin containing Epichlorohydrin and ethylene oxide.

    I do not know very much about chemistry but through some research I see that ethylene oxide can react with water to produce glycol. I also hear that PMMA can absorb water.

    Is it possible that there was enough water absorbed into the PMMA that the ethylene oxide reacted with it and formed a layer of glycol at the top?

    And my big question is, is there any easy way to test if the layer is ethylene glycol?

    Thanks a bunch

    dacruick
     
  2. jcsd
  3. Sep 29, 2010 #2

    chemisttree

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    Ethylene glycol is soluble in water in all proportions. Epichlorohydrin is slightly soluble.

    If you have a copper wire, pass it through a hot flame (blue flame from bunsen burner) and when cool, dip it into the liquid. Put that back into the flame and look for green. Green signifies chlorine and means that you have at least some epi in that sample. http://www.sha.org/research_resources/conservation_faqs/documents/beilstei.pdf"
     
    Last edited by a moderator: Apr 25, 2017
  4. Sep 29, 2010 #3
    I will try that. But to clarify, I do not have any water (or at least no water that I meant to have), in the resin. It was simply the resin and the acrylic only.

    originally I had the ethylene oxide and the epichlorohydrin, then I mixed in Triethylenetetramine which is the hardener for the resin. It has now completely cured and is a solid block of this resin, but with an oily substance on the top.

    bubbles have formed of this oily substance and if I had to guess, I would guess it is glycol.

    Thank you for your help, and in advance for any future help:).

    Oh P.S

    The bubbles are very small, I am concerned that I wont be able to scavenge enough of it to create a flame that is green.
     
  5. Sep 29, 2010 #4

    chemisttree

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    Don't worry, it's a very sensitive test.
     
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