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Quick question - orientation of a hydrophobic / hydrophilic molecule

  1. May 14, 2018 #1
    Hi,

    I am looking at how molecules with hydrophobic and hydrophillic properties move and orientate themselves in water. If I have say a PFOS molecule...

    fig1.png

    The hydrophobic part (the perfluoroalkyl group - the carbon chain) will move to the liquid surface but the hydrophillic part (the sulfonate part) will not want to go there. So will it go to the liquid surface at all?

    If I have many molecules what will their orientation look like? Will they be layered? It is hard to imagine.

    Any ideas as to what the orientation will look like or somewhere that has an image would really help.

    Thanks for any help.
     
  2. jcsd
  3. May 14, 2018 #2

    Borek

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    Staff: Mentor

  4. May 14, 2018 #3
  5. Sep 3, 2018 #4
    Just thought I will add a small detail...according to research conducted at U of Guelph (Canada), water at a hydrophillic surface forms a molecular layer of aligned water molecules and excludes all other molecules and hence Professor Gerald Pollack calls the effective molecular formation as EZ water (exclusion zone). The formation appears to explain surface tension and surface conductivity (free electrons). The question I have is whether the same formation is occurring at a phase surface; it should be, IMHO. Therefore I would expect the surfactant molecule in a dilute mixture, to be excluded from the surface, by one or more water molecular" pseudo-polymer" layers (my term as a former polymer physicist) . It appears that light absorption on the laboratory layout initiated more layers of EZ water to form.
     
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