<p>The thesis deals partly with methodology including construction</p><p>of hardware and new pulse sequences in the field of electrophoretic</p><p>NMR, and partly with practical use of ENMR and</p><p>diffusion NMR in the investigation of charged colloidal systems.</p><p>Several sources of artefacts are investigated, including gas production</p><p>at the electrodes, electroosmosis and Joule heating</p><p>effects that can cause convection. The electrophoretic double</p><p>stimulated-echo pulse sequence is introduced to suppress these</p><p>artefacts and to increase the feasible measuring range to higher</p><p>electric fields and conductivities.</p><p>The interaction between the non-ionic polymer poly(ethylene</p><p>oxide) PEO and differently charged surfactants is investigated</p><p>using the above mentioned methods. The investigated surfactants</p><p>are the anionic sodium dodecyl sulphate (SDS) and</p><p>potassium laurate (KC12), the cationic dodecyltrimethylammonium</p><p>bromide (CTAB) and the non-ionic octyl β-D-glucoside.</p><p>ENMR is also used to investigate two different mixed micelle</p><p>systems, with SDS as the charged surfactant component and</p><p>dodecyl malono-bis-N-methylglucamide (C12BNMG) respectively</p><p>tetra(ethylene oxide) dodecyl ether (C12EO4) as the nonionic</p><p>surfactant component. A method to calculate the degree</p><p>of counter-ion dissociation, αdissociation, as a function of composition</p><p>is demonstrated.</p><p>Finally diffusion NMR is used to compare transport dynamics</p><p>in gel electrolyte systems based on two differently grafted polymers;</p><p>one amphiphilic system containing polymethacrylate</p><p>grafted partly with polyethylene oxide and partly with fluorocarbons</p><p>and the corresponding nonamphiphilic system grafted</p><p>with only polyethylene oxide. Both systems contain the electrolyte</p><p>lithium bis(trifluoromethylsulfonyl) imide salt dissolved in</p><p>γ-butyrolactone. The results show that the system based on the</p><p>amphiphilic polymer has better transport dynamics and therefore</p><p>is more suited as material for battery</p>
| Identifer | oai:union.ndltd.org:UPSALLA/oai:DiVA.org:kth-119 |
| Date | January 2005 |
| Creators | Thyboll Pettersson, Erik |
| Publisher | KTH, Chemistry |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Doctoral thesis, comprehensive summary, text |
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