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This thesis is concerned with the dynamics and mechanical relaxation properties of three types of anisotropic rubbers. The main part of the work concentrates on Liquid Crystalline Elastomers (LCE). The first type of elastomer is a monodomain LCE synthesised from a route established by Finkelmann <i>et al.</i> The second elastomer is a polydomain LCE. Finally an elastomeric block copolymer is included in the work. A range of mechanical measurements were made to explore the physical properties of the materials over a wide range of temperatures. Stress/Strain, dynamic mechanical data and thermal expansion data are presented for certain materials. In addition, X-ray order parameter data is measured. Key findings from the work include the experimental observations of a reduction in shear modulus of the monodomain LCE at the nematic-isotropic transition and the result was found to be consistent with previously published theoretical modelling. In addition, thermal expansions changes at the nematic-isotropic transition were correlated with X-ray order parameter data and theoretical model. The effect of chain stiffness was systematically explored. Anisotropic elastic properties were established and time-temperature superpositions were explored for all materials. Some of the results presented in this thesis have appeared as publications.

This thesis documents the results of a structural and compositional study of selected mixed metal oxides possessing novel structures based upon 'ribbons' of corner sharing metal-oxygen octahedra. The techniques employed to characterise the specimens of interest have included Powder X-ray Diffraction (PXRD). High Resolution Transmission Electron Microscopy (HRTEM) and Energy Dispersive X-ray Spectroscopy (EDS). Compositional analysis of specimens containing strontium, lanthanum and titanium has been achieved to a high degree of accuracy using EDS analysis in the electron microscope. A mathematical technique based upon the intensity ratios of the X-ray emission lines has been developed to overcome the problem of overlapping lanthanum L and titanium K peaks in the X-ray emission specimen. The viability of the new technique has been proven using well characterised test specimens containing all three elements. An in-depth study of two compounds in the SrO-La₂O₃-TiO₂ system, Sr₃La₂Ti₂O₁₀ and Sr₈La₄Ti₅O₂₄ has been performed. Evidence from high resolution imaging and electron diffraction has confirmed that threes phases possess composite layer structures based upon corner sharing ribbons of TiO₆ octahedra. Their status as the n=4 and n=5 members of a homologous series Sr_2n-2La₄Ti_nO_4n+4, where the parameter n represents the number of TiO₆ octahedra in the ribbons, has also been established using EDS. However, results also suggest that these compounds may be metastable. The effect of niobium substitution on the structure of the n=1 Aurivillius phase, Bi₂WO₆, has also been investigated. Results from HRTEM have shown up to 25% of the tungsten can be substituted by niobium without any observable effect on the Aurivillius structure. Upon 50% niobium substitution, it appears that a structural modification takes place, as high resolution imaging and electron diffraction reveal a superstructure on the (012) or (013) planes of a Bi₂WO₆ sub-cell, which can be attributed to the presence of steps in the Aurivillius matrix at regular intervals.

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The physical processes occurring during nanotube deposition were investigated, and a nanotube growth model explained. A mass spectrometer was used to investigate the plasma chemistry. The role of NH₃ in suppressing C₂H₂decomposition and encouraging nanotube formation was demonstrated, and an optimum condition for clean nanotube production determined to be at a gas ratio of approximately 20% C₂H₂: 80% NH₃. The ability to selectively deposit nanotubes and nanofibres at pre-defined locations on a flat silicon substrate was demonstrated, and shaping of the silicon substrate using anisotropic wet chemical etching identified as a way to improve the field amplification factor of a nanotube device. Using a self-aligning process, individual nanofibres were successfully deposited on the tips of etched silicon pyramids. The importance of removing any molecular adsorbates from carbon nanofibres before commencing field emission measurements was shown. Following conditioning to remove adsorbates, an array of nanofibres on a flat substrate was measured to have a field amplification factor of approximately 400, and an array of nanofibres on a shaped substrate was measured to have a field amplification factor of approximately 1400. High voltage experiments resulted in irreversible field evaporation of atoms from the tips of the carbon nanofibres, causing a reduction in the field amplification factor. The vertical growth rate of carbon nanofibres during nanofibre deposition was shown to be proportional to the electric field in the plasma close to the tip of the growing nanofibre. An observed tailing-off of the vertical growth rate of isolated carbon nanofibres was attributed to the changing morphology of the catalyst particle resulting in the precipitation of amorphous carbon, which covers the particle and prevents further growth.

Synthesis of controlled quality and quantity of nanostructured materials form the basis of future nanotechnology building blocks. The understanding of fundamental properties, creation of complex hierarchical nanostructured materials and development of nanotechnologies are research areas which follow closely after the synthesis of nanomaterials. First and foremost, the key growth parameters of vapour-phase synthesis were identified so as to control the growth of nanomaterials with desired physical dimensions and chemical compositions. The synthesized nanomaterials were characterised using various chemical and structural analysis techniques in a complementary fashion. In addition, various self-assembly growth techniques were used to engineer the growth of complex nanostructures. The use of lithography; photolithography and ion beam lithography to generate micro to nano dimension catalyst patterns proved to be a valuable guide for selective growth of nanowires, whilst the use of zinc oxide polyhedron crystals and grain-boundary textured Cu templates have successfully produced a variety of interesting hierarchical nanostructures. Essentially, the templates act as a structure directing medium to intercede the growth in a confined manner. Success in the growth of one-dimensional single-crystal nanowires is the focus of interest since they offer the potential to answer fundamental questions about the effect of dimensionality on physical properties and are expected to play a central role in applications ranging from molecular electronics to scanning microscopy probes. Finally, with the availability of nanostructures in desirable crystal structures and chemical compositions, studies on their physical properties and phenomena were performed. Interesting properties such as the wettability and electrical properties were investigated. In particular, silicon carbide nanowire flowers show remarkable surface hydrophobicity and elasticity attributed to the unconventional multi-directional assembly of nanowires. The zinc oxide nanowires, on the other hand, exhibit superior electrical conductivity due to their clean surfaces and perfect crystallinity nature.

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