12 micelles

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General Principles for the synthesis of micelles

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Page 1: 12 micelles

General Principles for the synthesisof micelles

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What are micelles?

Micelles: Micelles are the simplest of all amphiphilic self-organizing structures.

A micelle is an aggregate of molecules in a colloidal solution, such as those in detergents.

Spherical micelle

Cylindrical micelle

Bicontinuous structure

Vesicles

Amphiphile is a term describing a chemical compound possessing both hydrophilic (water-loving, polar) and lipophilic (fat-loving) properties.

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Micelles (Aggregation Colloids)

Surfactants are compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid.

ApplicationsCleaning/Detergents (40%), Textiles, Cosmetics,Paper Production, Paint, Food, Mining (Flotation)......

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Ionic and Non Ionic Surfactants

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Micelles can be seen by Microscopic techniques

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The critical micelle concentration (cmc, ck)

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The critical micelle concentration (cmc, ck)

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Some values about micelles

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Solubility of Surfactants

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Solubility (More information) – Krafft Temperature

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Micelle formation mechanism

An aggregation number is a description of the number of molecules present in a micelle once the critical micelle concentration (cmc) has been reached.

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Micelle formation mechanism

An aggregation number is a description of the number of molecules present in a micelle once the critical micelle concentration (cmc) has been reached.

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The Concept of packing parameter P

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Prediction of the shape of self assembled structures in a solution

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Predictions of the packing parameter concept

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Additional Topics for interested students

Anybody interested in the topic can also read stuff on

1.The free energy model by Tanford2.The free energy model by Tanford and the equilibrium headgroup area ae3.Some successful predictions of the packing model4.Possible misinterpretation of the packing parameter P5.Neglected role of the surfactant tail!!6.Influence of tail packing constraints7.Why don’t oil and water mix? The “hydrophobic effect”8.Water is not a normal liquid! The “iceberg model”9.Small-Size Model: Is the disaffinity of oil for water due to water’s small size?