Sökning: "Polymer-surfactant association"
Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Polymer-surfactant association.
1. Association Phenomena in Aqueous Solutions of Surfactants and Hydrophobically Modified Polymers
Sammanfattning : Interactions between ionic surfactants (sodium dodecyl sulfate and dodecyltrimethylammonium chloride) and nonionic polymers ((hydroxyethyl)cellulose, ethyl(hydroxyethyl)cellulose and their hydrophobically modified analogous) have been studied by means of rheology, pulsed field gradient nuclear magnetic resonance (PFG NMR), time-resolved fluorescence quenching (TRFQ), dynamic light scattering (DLS) and cryo-transmission electron microscopy (cryo-TEM). In all experiments surfactants have been added in various amounts to polymer solutions at fixed concentrations. LÄS MER
2. Phase Behavior and Solution Properties of Aqueous Polyion-Surfactant Ion Systems
Sammanfattning : Polyelectrolytes and oppositely charged surfactants interact through attractive electrostatic forces, which in many cases lead to phase separation already at low total concentrations. During the past 10-15 years investigations of these systems have been simplified through the use of complex salts that consist of surfactants with polymeric counterions in a 1:1 charge stoichiometry (no excess simple counterions present). LÄS MER
3. Association Phenomena Involving Hydrophobically Modified Polymers. Electrostatic and Hydrophobic Contributions
Sammanfattning : The electrostatic and hydrophobic interactions in aqueous solutions of hydrophobically-modified water-soluble non-ionic or ionic polymers, their mixtures with a second polymer, nonionic or of opposite charge, and their mixtures with surfactants of opposite charge have been investigated. The relative strength of the electrostatic and hydrophobic contributions has been modulated by a variation of the polymer charge density and the solution pH, and by a variation in the degree and strength of the hydrophobic modifications, respectively. LÄS MER
4. Surfactant Responsive Cross-Linked Polymer Hydrogels
Sammanfattning : The focus of the thesis is on chemically cross-linked hydrogels which drastically change their volume when immersed in solutions of different ionic surfactants (with or without added salt). The two main questions addressed are: (1) How useful are simple gel swelling experiments to the study of polymer-surfactant interactions?, and (2) How does the volume of a cross-linked polymer gel change when it is immersed in a surfactant solution, both with respect to the equilibrium swelling and with respect to transient volume changes? Most of the gels studied were prepared by cross-linking linear polymers, which were well studied derivatives of hydroxyethyl cellulose (HEC). LÄS MER
5. Associative Multicomponent Polymers in Bulk and at Interfaces
Sammanfattning : The solution and interfacial properties of an associative water-soluble cellulose derivative, ethyl(hydroxyethyl)cellulose (EHEC) have been investigated. Main themes have been to study the effect of hydrophobic modification of the polymer (HM-EHEC) and the interactions with surfactants, both in bulk and at interfaces. LÄS MER
