Quick question - orientation of a hydrophobic / hydrophilic molecule

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SUMMARY

The discussion centers on the orientation of hydrophobic and hydrophilic molecules, specifically focusing on PFOS (perfluorooctanesulfonic acid). The hydrophobic perfluoroalkyl group tends to migrate to the liquid surface, while the hydrophilic sulfonate group resists this movement. Research from the University of Guelph indicates that water at hydrophilic surfaces forms a structured layer of aligned water molecules, termed EZ (exclusion zone) water, which may exclude surfactant molecules from the surface. This phenomenon is crucial for understanding molecular orientation in dilute mixtures and its implications for surface tension and conductivity.

PREREQUISITES
  • Understanding of hydrophobic and hydrophilic interactions
  • Familiarity with PFOS molecular structure and properties
  • Knowledge of exclusion zone (EZ) water concept
  • Basic principles of surface tension and molecular layering
NEXT STEPS
  • Research the molecular orientation of surfactants in aqueous solutions
  • Study the effects of EZ water on surface tension and conductivity
  • Explore the implications of molecular layering in polymer physics
  • Investigate experimental methods to visualize molecular orientation in liquids
USEFUL FOR

Chemists, polymer physicists, and researchers studying molecular interactions in aqueous environments will benefit from this discussion, particularly those interested in surfactant behavior and surface phenomena.

rwooduk
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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.
 

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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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