This thesis reports an experimental investigation of the structural, dynamical and glass formation properties of model polymer-nanoparticle mixtures, focusing in particular on polystyrene (PS)-fullerene (C60) nanocomposites, both in the bulk and in thin films. We show that the addition of C60 alters the glass formation and dynamics of PS in a non-trivial manner. Combining present differential scanning calorimetry (DSC), dielectric spectroscopy (DS) and previous inelastic neutron scattering (INS) experiments, we find that C60 slows down the chain segmental ( α) relaxation of PS, causing an increase of the glass transition temperature (Tg), dynamic fragility (m), and α relaxation time (Tα ), while also increasing the amplitude of atomic vibrations in deep glassy state, as seen by an increase in mean-square displacement of hydrogen motion. These findings are interpreted as disruption to molecular packing and an increase of free volume in the glass state. General trends in dynamics and glass formation induced by different classes of nanoparticles are compiled and critically interpreted. Specifically, changes to Tg and fragility appear to result from the interplay between the bulk molecular packing state of the nanocomposite glass and both the polymer-nanoparticle interaction strength and interfacial area. Nanoparticle size and dispersion are therefore of paramount importance and a systematic C60 aggregation study using small angle neutron scattering (SANS) and wide angle X-ray scattering (WAXS) was thus carried out. Conditions and limits for miscibility of PS-C60 nanocomposites, at relevant processing steps, were investigated and relevant miscibility and dispersibility thresholds established. The C60 fullerenes are found to associate into fractal-like objects in bulk nanocomposite mixtures, upon annealing above the miscibility concentration and temperature, following asymptotic kinetics. In thin films, however, C60 association is bound by 2D film confinement and the resulting nanocomposite thin film structure changes qualitatively. At low nanoparticle loading, we observe sparse C60 nucleation, accompanied by crystallisation, which is well described by Avrami relation. At increasing C60 concentration, up to the dispersibility limit, a novel nanoparticle self-association mechanism is observed, coined "spinodal clustering". This process yields remarkably regular spinodal-like morphologies of C60 clusters with tuneable characteristic spatial frequency and amplitude, which coarsen with time following well-defined scaling laws, analogous to those of 2D phase separation of binary mixtures. Mapping of this self-assembly process in thin films utilised a combination of optical microscopy (OM), atomic force microscopy (AFM) and neutron reflectivity (NR) techniques. Unexpectedly, photo-illumination is found to affect thin film stability and morphology network. Combined, these allow further tuneability of nanocomposite thin film morphology and yield ultrathin films with unprecedented mechanical integrity and stability at elevated temperatures. Coupling the fundamental processes presented in this thesis, namely the photo-chemical transformation of C60, the spinodal clustering and thin film dewetting of nanocomposite thin films, we introduce a novel self assembly photopatterning approach which is both cheap and procedurally simple. Various technological applications are envisaged in the fields of organic photovoltaics (bulk heterojunctions morphology), rapid pattern assembly (fabrication of polymer-based plastic electronics) and functional hierarchical coatings (ultrathin stable lms). A prototype "circuit" device has been fabricated as a proof of principle and is shown on the cover image.

'Structured liquid' detergent products have received much attention as a means of providing liquid detergent compositions with special rheological and other properties. These include the ability to suspend particles and storage stability at ambient temperatures. The challenge is to prevent separation of the product into two or more layers (which requires a high viscosity) while controlling the rheology to allow a sufficient ease of pouring acceptable to the consumer. Liquid laundry detergent compositions are generally formulated with a variety of active ingredients, typically one or more anionic surfactants, often in combination with a nonionic surfactant and detergent builder materials such as electrolytes. The microstructure of these 'liquids' (determined by the product formulation, process conditions and procedures) strongly influences the macroscopic properties such as rheology. In this work, the microstructure, rheology and aging of a range of model structured liquid have been studied. The model systems are complex aqueous mixtures of sodium alkylbenzene sulphate (LAS), sodium alkyl ether sulphate (SLES) and primary alcohol ethoxylate (NEODOL 25-7). The dependence of the phase microstructure on sample composition was investigated by added different amount of electrolyte (tri-sodium citrate, TSC) in the model system. The physical appearance of these systems varied from transparent to milky depending on the concentration of the electrolyte. All were viscous 'gels'. Optical microscopy and SAXS have been used to elucidate the basic microstructure, its variation with electrolyte concentration and temperature on the angstrom to micrometer length scale. Deuterium nuclear magnetic resonance (2H NMR) spectroscopy on 2H2O-enriched samples has been used to provide information about the phase behaviour of the liquid crystalline systems. Changes in spectral line shape and water quadrupole splittings are presented and discussed as a function of sample composition, temperature and aging process. The shear-alignment process of the lamellar microstructure has been examined including Linkam optical shear cell, AR 2000 rheometer and 2H Rheo-NMR. A variety of rheological patterns including simple stress sweeps and oscillatory rheology have been investigated and provided information about the effect of shear, shear time and nature of deformation of the model structured liquids. In this context, the relaxation kinetics of the shear-induced structures has been investigated using 2H Rheo-NMR spectroscopy.

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A range of dense polycrystalline liquid phase aluminas was prepared by hot-pressing . and pressureless sintering methods with calcium silicate additions of 0.5, I, 5 and 10% by weight. The CaO:Si02 ratio varied betWeen 1:10 and 10:1. The microstructures wer~ systematically studied using analytical scanning electron microscopy (SEM) and' transmission electron microscopy (TEM) combined with energy dispersive X-ray (EDX) spectrometry and electron energy loss spectrometry (EELS). These techniques . allowed the direct imaging of' secondary· crystalline phases and amorphous films at grain boundaries and at triple pockets as well as both a qualitative and semiquantitative determination of their composition and chemistry. The, specific composition of the glassy phase ([Ca]:[Si]:[AI] atom ratios) was found to vary from grain boundary to triple pocket and also with the exact additive composition. Wet erosive wear rates, Vickers hardness and impedance spectroscopy measurements were investigated along with residual stress measurements caused by thermal expansion coefficient mismatches between alumina grains, glassy and secondary and crystallised phases observed in the microstructures. Silica rich samples were found to exhibit greater wear resistances, and residual stresses. The varying wear resistance obs'erved between specimens may also be attributed to dislocation arrays, strain and microcracks observed within the microstructure along with the intergranular film composition and additive chemistry. Grain size was also found to be a controlling factor of wear rate and hardness. Silica phases also acted to increase the resistance and capacitance of the grain boundaries as measured by, impedance spectroscopy.

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