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Visar resultat 1 - 5 av 13 avhandlingar som matchar ovanstående sökkriterier.
1. Mixed Block Copolymer Solutions: Self-Assembly and Interactions
Sammanfattning : This thesis incorporates studies on the aqueous systems of two types of thermoresponsive amphiphilic block copolymers; a series of nonionic triblock copolymers comprising blocks of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) denoted as PEO-PPO-PEO block copolymers, and a series of ionic diblock copolymers consisting of one charged block and one block of poly(N-isopropylacrylamide) (PNIPAAM). Various techniques, such as dynamic and static light scattering (DLS and SLS), small angle X-ray and neutron scattering (SAXS and SANS), high sensitivity differential scanning calorimetry (HSDSC), turbidimetry, electrophoretic mobility measurements, and two-dimensional proton NMR nuclear Overhauser effect spectroscopy (2D 1H NMR NOESY), were applied to study these block copolymer systems. LÄS MER
2. Molecular Association Studied by NMR Spectroscopy
Sammanfattning : This Thesis presents studies of molecular association in aqueous solution and at the liquid/solid interface. The investigated molecular systems range from self-aggregating surfactants to hydration water in contact with micelles or individual molecules. In most studies, combinations of various NMR methods were applied. LÄS MER
3. Biodegradable Surfactants Containing Hydrolyzable Bonds
Sammanfattning : Surfactants with built-in weak bonds, so-called cleavable surfactants, are interesting candidates in the search for more environmentally friendly alternatives to traditional surfactants. The objective of this thesis was to perform a systematic study in which cleavable surfactants with different hydrolyzable bonds were compared with regard to physicochemical properties, and chemical and biological stability. LÄS MER
4. 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
5. Catanionic Surfactant Mixtures and Binary Systems of Modified Fatty Acid Surfactants. Phase Equilibria and Structure
Sammanfattning : Surfactant self-assembly is an important phenomenon that occurs in a number of processes in our everyday life. It is important to understand the forces and parameters that control and influence the self-assembly, as this knowledge can be used both in order to design surfactant systems with desired properties and for creating model systems, for example for biological processes. LÄS MER