Electrolytes of poly(trimethylene carbonate-co-ε-caprolactone), poly(TMC-co-CL), and LiTFSI have been prepared and characterised. The copolymers were analysed with GPC and NMR, which showed that random high molecular weight copolymers of desired compositions had been obtained. The electrolytes with varied salt concentration were examined with TGA, DSC, FTIR and impedance spectroscopy. The highest ionic conductivities were measured for the copolymer of 60:40 ratio of TMC:CL and for the homopolymer poly(ε-caprolactone), PCL, both electrolytes with 28 wt% LiTFSI. The ionic conductivity was measured to of the order of 10−3 S cm−1 for the PCL electrolyte and 10−4 S cm−1 for the 60:40 copolymer at 50 °C.

Thèse - Faculté des sciences de Paris.

Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 110-114).

In traditional theories for electrolyte solutions the solvent is treated only as a dielectric continuum. A more complete theoretical picture of electrolyte solutions can be obtained by including the solvent as a true molecular species. In this thesis we report results for the structural, thermodynamic, and dielectric properties of model electrolyte solutions which explicitly include a water-like molecular solvent. The ions are modelled simply as charged hard spheres and only univalent ions are considered. The water-like solvent is also treated as a hard sphere into which the low-order multipole moments and polarizability tensor of water are included. The reference hypernetted-chain theory is used to study the model systems. The formalism of Kirkwood and Buff is employed to obtain general expressions relating the microscopic correlation functions and the thermodynamic properties of electrolyte solutions without restricting the nature of the solvent. The low concentration limiting behaviour of these expressions is examined and compared with the macroscopic results determined through Debye-Hückel theory. The influence of solvent polarizability is examined at two theoretical levels. The more detailed approach, the R-dependent mean field theory, allows us to consider the average local electric field experienced by a solvent particle as a function of its separation from an ion and is shown to have an effect upon the limiting laws of some thermodynamic properties. Model systems for liquid water are investigated over a large range of temperatures and pressures and are found to have dielectric constants which agree reasonably well with experiment. Model aqueous electrolyte solutions are studied both at infinite dilution and at finite concentration, but only at 25°C. The equilibrium dielectric constants of these solutions are qualitatively consistent with those of experiment. A remarkable diversity of behaviour is obtained for our model solutions by simply varying the hard-sphere diameters of the ions. In many cases the behaviour observed for thermodynamic quantities is in accord with experiment. The ion-ion, ion-solvent and solvent-solvent correlation functions of the solutions are examined in detail, revealing a wealth of structural information. Ionic solvation is generally found to be very sensitive to the details of the interactions within the system. / Science, Faculty of / Chemistry, Department of / Graduate

1. Two aspects of long-term salt and water excretion were measured in Glaucous-winged Gulls, Larus glaucescens. Total body water volume and turnover rate were measured in birds drinking fresh water and drinking sea water by THO disappearance rate. Na+, K+, and CI- excretions over 24 hours were measured by continuous collection of cloacal and salt gland excretions from birds fed fish, fish plus a salt load, or a salt load only. 2. Total body water volume was found to be 79% of body weight on both fresh water and sea water drinking regimes. TBW volume is large compared to other birds. 3. Mean total body water turnover rate was the same for both drinking regimes (0.064 ml/g-day); this value is the same as the predicted rate based on data from other birds. 4. There were no significant differences between the fish and fish salt fed birds in the pattern or amounts of ion excretion. 5. Sodium and chloride were excreted in approximately equal amounts from the salt gland and cloaca. Most potassium was excreted via the cloaca. Thirty-eight percent of the total sodium, 6% of the total potassium and 58% of the total chloride excreted were contained in the salt gland secretion of both the fish and fish + salt groups of gulls. 6. The fluid and solid portions of the cloacal excretion were analyzed for ions. Cations were divided between the two portions. In the fish and fish + salt fed birds, 51.8 + 7.8% of the cloacal Na+ and 61.8 + 4.5% of the cloacal K+ was found in the solid portion of the cloacal excreta. Chloride was detected in the fluid portion only. 7. The two birds given only a salt load had lower rates of evaporative water loss and smaller amounts of cloacal solids compared to the fed birds. 8. The large TBW volume may be advantageous to marine birds as a buffer against excess salt ingestion. The constancy of TBW turnover rate suggests that the gulls are specifically adapted to their environment where salt, but not water, is a stress. 9. The results suggest that the salt gland, cloacal fluids and especially the cloacal solids are important routes for ion excretion for fed birds and that osmoregulatory processes for fed and unfed birds may be different. 10. These data imply that although the salt gland is the primary adaptation of marine birds to salt stress, the entire process of salt and water metabolism also involves other more subtle mechanisms. / Science, Faculty of / Zoology, Department of / Graduate

<p>The polyelectrolyte titration method has been developed overthe years in order to determine the surface charge ofcellulosic fibers. The conditions have been varied depending onthe author. This work has been aimed at resolving theappropriate conditions for measuring the charge, such aselectrolyte concentration and molecular mass of thepolyelectrolyte. The charge ratio of variously treated pulpswas also investigated.</p><p>The polyelectrolyte titration technique is based on a 1:1adsorption stoichiometry between fiber and polyelectrolytecharges. Adsorption of polydiallyldimethylammonium chloride(poly-DADMAC) was first performed at various electrolyteconcentrations and then with various molecular masses. ESCA(Electron Spectroscopy for Chemical Analysis) was used toindependently validate the polyelectrolyte titrationmethod.</p><p>Results showed that stoichiometry prevailsat lowelectrolyte concentrations. Increasing the electrolyteconcentration screens the fiber charges, initially enhancingthe adsorption and causing a deviation from stoichiometry.Further increases in electrolyte concentration eventuallydecrease the adsorption. Deviation from stoichiometry occurredat higher electrolyte concentrations for higher charge densitypulps. ESCA-measurements showed that high and low molecularmass cationic polyelectrolyte adsorb to the same extent on thefiber surface, confirming stoichiometry. There was a goodagreement between the two techniques, hence, thepolyelectrolyte titration technique is a good method to measuresurface charges. Comparing the charge ratio between differentkind of pulps and treatments, it was found that mechanicalpulps have a higher surface charge than chemical pulps. Thecharge ratio of chemical pulps was, however, practicallyunchanged when comparing different types of wood and bleachingsequences.</p><p><b>KEYWORDS:</b>Adsorption, electrolyte, polyelectrolyte,polyelectrolyte titration, charge stoichiometry, charge ratio,diffuse electric double layer, Debye length, poly-DADMAC,cellulosic fibers, ESCA.</p>

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