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Thin films of fluorocarbon-based polymers can be deposited by plasma assisted polymerisation of various perfluorocarbons. The chemical natures of plasma polymers of hexafluoropropene and perfluorohexane were examined as a function of power, flow rate and position in reactor. Polymerised hexafluoropropene displayed increased fluorine contents at high powers; this is at odds with perfluorohexane which demonstrated lower fluorine contents. Differing reaction mechanisms between saturated and unsaturated perfluorocarbons were proposed to explain this. Both perfluorocarbons were found to give increased CF(_2) contents out of the plasma glow region. This was demonstrated to be a function of distance from the monomer inlet, and was ascribed to the production of long lived polymer forming species in the gas phase. Plasma oxidation of low density polyethylene, polystyrene and poly (ether ether ketone) with oxygen and carbon dioxide was modelled by corresponding photooxidation reactions. Correlations between the structure of the polymer, the treatment used, and the final products were drawn. Aliphatic components tended to give carbon-oxygen single bonds, phenyl rings were oxidised to carbonyl and acid groups, and carbonyl groups to acids. Metal-containing polymeric thin films were produced from plasmas of zinc acetylacetonate and aluminium tri-sec -butoxide. The products from each monomer were different, with the zinc compound resulting in a high proportion of zinc carboxylate and the aluminium compound giving the oxide or hydroxide. Incorporation of these compounds into a perfluorohexane plasma resulted in the formation of metal fluoride containing thin films.

The development of sample introduction techniques for solid materials is a desirable goal in analytical atomic spectrometry. Traditional techniques have involved the introduction of samples as liquids by processes such as nebulisation. However some solid materials are not readily amenable to dissolution procedures and for the determination of elements at the ultra-trace level the reagents used for dissolution may produce undesired contamination. An additional problem for such determinations is that the dissolution process- may dilute the sample below the level which can be measured by the selected technique. The relative merits of three techniques for the introduction of solids for inductively coupled plasma optical emission spectroscopy (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) have been evaluated in this thesis. The techniques studied were a laser ablation system based on a Nd:YAG laser, slurry nebulisation and an electrothermal vaporisation (ETV) system. The parameters which affect the performance of these techniques have been discussed. The application of each technique to the analysis of some geochemical samples has been described. Results are presented for the determination of various elements in fly ash and standard rock samples. The results obtained for each technique are compared. A value of merit has been defined to allow comparison of the results in this thesis with results published in the literature. A comparison of the plasma source in the presence and in the absence of water has been included in this thesis. Ionisation temperature and electron number density measurements were made usinq traditional nebulisation and compared to those obtained using laser ablation.

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