Micelle: Difference between revisions

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== Formation ==
== Formation ==


The micelle packing parameter equation is utilized to help "predict molecular self-assembly in surfactant solutions":<ref name="r2">Nagarajan, R. 2002. "Molecular Packing Parameter and Surfactant Self-Assembly: The Neglected Role of the Surfactant Tail†". Langmuir 18: 31. http://pubs.acs.org/doi/abs/10.1021/la010831y</ref>
Micelles form when the polar head and the non polar tails arrange in a special way. They are usually driven to arrange either with the polar heads out (oil in water) or with the polar head in (water in oil). Micelles only form when the concentration of surfactant is greater than the critical micelle concentration. The surfactant is any surface active material that can part the surface upon entering. The higher the critical micelle concentration, the more micelles there are. Micelle formation also depend on the Krafft temperature. If the temperature is below the Krafft temperature<ref name="r2">Friedrich Krafft. 2015. In Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/w/index.php?title=Friedrich_Krafft&oldid=668396294</ref>, then there is no spontaneous formation of micelles. As the temperature increases, the surfactant will turn into a soluble form and be able to form micelles from a crystalline state. The hydrophobic effect is also a driving force that needs to be taken into account. This effect is characterized by the fact that like to form intermolecular aggregates in aqueous substances and in intramolecular molecules. Micelle formation can be summed up by thermodynamics, driven by entropy and enthalpy.
 
The micelle packing parameter equation is utilized to help "predict molecular self-assembly in surfactant solutions":<ref name="r3">Nagarajan, R. 2002. "Molecular Packing Parameter and Surfactant Self-Assembly: The Neglected Role of the Surfactant Tail†". Langmuir 18: 31. http://pubs.acs.org/doi/abs/10.1021/la010831y</ref>


[[File:Micelle Packing Eq.png|left|text-top|Micelle packing eq.]]
[[File:Micelle Packing Eq.png|left|text-top|Micelle packing eq.]]
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where [[File:Vo.png|top]]&nbsp;<span style="line-height: 1.6;">is the surfactant tail volume, [[File:Lo.png|top]]&nbsp;is the tail length, and [[File:Ae.png|top]]&nbsp;is the equilibrium area per molecule at the aggregate surface.</span>
where [[File:Vo.png|top|Vo.png]]&nbsp;<span style="line-height: 1.6;">is the surfactant tail volume, [[File:Lo.png|top|Lo.png]]&nbsp;is the tail length, and [[File:Ae.png|top|Ae.png]]&nbsp;is the equilibrium area per molecule at the aggregate surface.</span>


== Role in oil emulsion ==
== Role in oil emulsion ==
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