Most ceramic articles are produced by first dispersing powders in a suitable liquid, forming the dispersion (by casting, molding, extrusion, etc.), drying and then firing the body to its final sintered state. It has been recognized that dispersion characteristics strongly affect the green body which in turn determines properties of fired ceramic, and recently, dispersion science has become quite important in the development of ceramics processes. In this thesis research, colloidal size alumina powder was dispersed in secondary butyl alcohol with a phosphate ester dispersant. Dispersions were produced in an attrition mill and evaluated by viscometry and sedimentation. These dispersions were "optimized" by adjusting surfactant concentration and milling time. Zeta potential measurements indicated stabilization was not purely electrostatic. It was noted that a small amount of water added to the dispersions dramatically affected dispersion rheology. With slight water addition high solids content slurries (40 vol. percent) could be produced with rheological characteristics desirable for casting. Solution conductivity measurements were made to provide insight into the possible mechanism by which water affects dispersion stability.

A method for the synthesis of submicron copper coated polystyrene particles by electroless deposition has been developed. In this technique, the carboxylated and sulfated polystyrene latex particles of 0.1 μm and 0.24 μm diameter, are first activated by conditioning in a solution of tetraammine palladium (II) chloride monohydrate and then plated in an electroless bath containing cupric sulfate, EDTA-disodium salt, some stabilizers and basic formaldehyde at 72 ± 1°C. The interaction between carboxylic acid groups and Pd(NH₃)₄Cl₂.H₂O has been studied using uv spectroscopy. Copper coated carboxylated polystyrene particles with a mean diameter of 0.4 μm and a standard deviation of 9% of the mean diameter have been synthesized. The size, shape and purity of these particles have been determined by SEM, EDX, and ESCA analysis. The microcrystallinity of the particles has been determined by XRD technique.

Phase separation in glass systems has been studied since the turn of the century, and has developed commercial interest with the VYCOR process and recent interest in glass-ceramics. Phase separation has been studied in the lead borate glass system because it is known to separate across a fairly wide compositional range, and has been shown to undergo both stable and metastable phase separation. To further understand immiscibility in the lead borate system, an investigation has been performed to determine the immiscibility gap under nearly equilibrium conditions. Small-angle x-ray scattering (SAXS) has also been used in an attempt to characterize the kinetics of phase separation of a high-lead composition in the metastable region, using novel sample preparation methods.

Copper aluminosilicate (composition Cu₂O·Al₂O₃·6SiO₂) glass was melted in an alumina crucible at 1500°C and air cooled in situ. A layer of cupric oxide was grown on the polished glass surface and its thickness measured using a scanning electron microscope (SEM). The thickness of the oxide layer was found to increase parabolically with time, with a temperature dependency that was compatible with the diffusion of copper through the layer. The cupric oxide layer was reduced to copper on roughened and polished glass surfaces using a gas mixture of 3% H₂ and 97% N₂, resulting in a glass substrate coated by copper. Adherence of the copper layer to the polished glass substrate was found to be poor. However, adherence was found to increase by roughening the surface before oxidation. Additions of NiO and CaO to the base glass were not detrimental to the production of the copper film.

Various coolant chemicals are known to have enhancing and suppressing effects on wear and the quality of finish, but little has been understood about the nature of these effects. Studies were performed to examine the effects of pH and surface bias on wear, subsurface damage, and the various theories of chemical interaction with the wear process. Results of this examination of wear suggest that chemical adsorbates can play a significant role in wear fracturing. Previous observations of plastic mechanisms in brittle wear have lead tribologists to suggest that chemically induced changes in plasticity are the cause of these effects. Instead, this thesis contends occurrence of plastic effects to be by-product of localized hydrostatic compression and insufficient stress intensity to cause fracture. Crack rates and stress intensities required for fracture to occur are known to vary with adsorption.

In this work a new wet-chemical method of preparing tungsten oxide thin films is described. This involves the dissolution of tungsten metal in aqueous hydrogen peroxide and reaction with acetic acid to form an alcohol-soluble precursor. All synthesis stages of this new precursor, termed peroxotungstic ethoxide, are characterized to determine possible reactions. The chemical and microstructural evolution of films is described as a function of firing temperature, utilizing infrared spectroscopy, diffraction and other optical data. A novel method of increasing the crack-free thickness of the films is given: a combination of oxalic acid dihydrate as a solution additive and film firing under controlled humidity. With this combination, fired crack-free films up to one micron in thickness were prepared. Oxalic acid dihydrate roughened and also caused crystallization of these films at lower temperatures (250°C) than expected. These rougher films exhibited an improved electrochromic response, as measured by optical and electrochemical characterizations.

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Multilayer polymer systems are a focus of increasing research effort motivated by the possibility to realize compact and flexible energy storage and energy harvesting devices. However, the performance and stability of these polymer systems are highly dependent on temperature. In this study the structure of monolayer ferroelectric polyvinylidene fluoride (PVDF) thin films and the relaxation dynamics as a function of temperature are characterized using XRD, FTIR and second harmonic generation (SHG). Multilayered ferroelectric polyvinylidene fluoride (PVDF) systems are fabricated using enabling technology in co-extrusion for increased energy storage and energy harvesting efficiency as well as increased stability at elevated temperatures. To understand the physics of why these multilayered systems perform better than single layer PVDF characterization techniques using second harmonic generation (SHG), electric field induced second harmonic (EFISH) and Raman laser spectroscopy are developed. Results show that the combination of Raman and SHG is a very sensitive, non-destructive and versatile technique that can be used to study the ferroelectric and structural properties of these systems. The addition of the EFISH technique allows the interrogation of structural and dielectric properties within individual layers and at the interfaces.

An Ion Selective Conductimetic Microsensor (ISCOM) for the detection of cesium ions was devleoped. The operating principle of an ISCOM is based on the concentration dependant change in the bulk conductivity of an ion selective membrane. Changes in conductivity are achieved by salt extraction of the target ion into the bulk of the membrane that is formed on top of a planar interdigitated electrode, thus allowing the monitoring of the membrane conductivity. Characterisation of the planar interdigitated electrode was undertaken using numerous techniques. This that that there was considerable inter-diffusion of the elemental layers comprising the subsurface structure of the electrode and allowed the identification of chromium as a contaminant. This was reported back to the electrode manufacturers and subsequently removed. Thermodynamic analsysis indicated that the elements of the surface of the electrode would not present any problems (background signal etc) during the normal operation of the ISCOM device. A method for the deposition of the ion selective membrane onto the electrode was developed. Initially the membrane was formed in a well on the electrode surface that was created by the lamination of additional layers onto the device structure. This method was abandoned due to the high failure rates of these devices caused by solution seepage under the laminated layer resulting in it peeling away from the electrode structure. The second method used was the forming of a membrane by direct drop coating i.e. application of a drop of the membrane on to the electrode. This work indicated that greater sensitivity could be obtained with thinner membranes. The final method to be used was the spin coating of the ion selective membrane onto the electrode surface. This work demonstrated that the greatest sensitivity, and response times of less than 15 seconds, were achieved when spin coating was conducted at speed of 1000 rpm or grater. In addition to this the response of the ISCOMs was found to linearly related to the square root of the target ion concentration. An analysis of the eeffect on device sensitivity of the composition of the ion selective membrane in terms of the relative level of membrane components was undertaken usign the experimental design software MODDE 6.0. This showed that the optimal membrane composition was 10% ionophore, 20% polymer and 70% pasticiser. Such membrances have a limit of detection of 4.95 x 10 M cesium. The selectivity of the cesium ISCOM was analysed using a semi-empirical method develoepd for this sensor from data generated using a method based on teh Fixed Inference Method (FIM) for the determination of ISE selectivity. It was found that the selectivity of the cesium ISCOM was comparable to that reported for ISEs. Particularly the interference by rubidium in the ISCOM system is the lowest of any sensor system reported to date with logks value of -2.22. The results for preliminary investigations into the device lifetime are also presented.