Skip to Main content Skip to Navigation
Theses

Effet de contre-ion sur les propriétés d'amphiphiles cationiques

Abstract : In this work, we studied dimeric cationic surfactants for which the counterion nature has been varied with the aim of determining which are the main ionic effects influencing the aggregation properties in water.
The methods of synthesis for these molecules were adapted so that the molecules can be distinguished by a large variation of counterions. The micellization of these surfactants has been studied by conductimetry and shows the great influence of hydrophobicity of the counterion associated with secondary effects such as counterion hydration and morphology. The ionization degree of cationic micelles is a fundamental parameter which is related to the hydration of the micellar surface, which depends on the nature of the counterion. We have also shown how a dye, the Methyl Orange, can be used to prove the hydration and ionisation of micelles. The solubility of these surfactants in water varied a lot with counterions as shown with the important variation of the Krafft temperature. The morphologies of the assemblies in aqueous solution were also studied by optical and electron microscopy. The last part is devoted to a particular family of double chained monocationic surfactant complexed with anionic mononucleotides. The properties and the morphologies of aggregates of these nucleolipides were examined, which allowed us to show that the confinement of chiral nucleotides on the cationic membranes can lead to an emergence of supramolecular chirality. We have also shown that these assemblies are influenced by a specific intermolecular interaction.
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00250098
Contributor : Sabine Manet <>
Submitted on : Sunday, February 10, 2008 - 1:31:37 AM
Last modification on : Thursday, January 11, 2018 - 6:21:12 AM
Long-term archiving on: : Monday, May 17, 2010 - 8:03:31 PM

Identifiers

  • HAL Id : tel-00250098, version 1

Collections

Citation

Sabine Manet. Effet de contre-ion sur les propriétés d'amphiphiles cationiques. Autre. Université Sciences et Technologies - Bordeaux I, 2007. Français. ⟨tel-00250098⟩

Share

Metrics

Record views

877

Files downloads

8490