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Chapter 1 introduces the background and importance of this thesis. Poly (ethylene terephthalate) (PET) is one of the most important polymer materials for industrial fields because of the good properties caused by its crystallinity, especially, control the kinetics of crystallization is a key technology for the productivity. Therefore, it is very useful to investigate the kinetics and mechanism of PET crystallization in detail. Usually, studies of crystallisation have focused only on the bulk state, but the surface is important in many practical materials, and there is reason to suppose that the mechanisms and kinetics of crystallisation in bulk and surface may be very different. Chapter 2 described the methodologies and theories of the experiments used in this study, that is, the protocol behind making thin PET samples, and the measurements used to study them; ellipsometry, atomic force microscopy, and grazing incidence X-ray scattering. In Chapter 3, how to make good samples, that is, the improvement in the surface roughness of thin PET films, was described in detail. The difficulty of making thin PET film samples was shown by reference to the literature and my original data, and the procedure introduced dealt successfully with these problems by choosing good combinations of solvents and making samples under suitable condition. In Chapter 4, I turn to sample aging, that is, the period after the sample is made, which strongly influences the kinetics or effectiveness of the crystallization, especially in the early stage (the induction time). I hypothesised that this aging effect was caused by a relaxation related to molecule conformations, that is, the relaxation by annealing before crystallization, which should increase the trans conformation. This is similar to the order of the PET molecules in the crystal, so pre-ordering or nucleation should take place more easily after this conformational change. In Chapter 5, the major data of this study, obtained by GI-WAXS, ellipsometry, and AFM, are introduced. Before crystallization starts, there was an intermediate state, which was clearly different from both the amorphous and crystal states in the morphology. The size of this structure was around from 10 to 30 nm. This should be the pre-ordering present in thin PET film. The validity of results of measurements related to the pre-ordering and whether it detects the pre-ordering or not were discussed with the literature in Chapter 6. The length scale of the pre-ordering measured in this study was similar to the literature in which pre-ordering has previously been detected in bulk samples. And the influences of film thickness and annealing temperature were also discussed. Differences of crystallization and pre-ordering between bulk and thin films of PET with detailed data of kinetics were shown in Chapter 7. Basically, induction time and the crystal growth rate of thin films were longer and slower than those in the bulk as measured by ellipsometry. The explanation for this should be from the “thickness effect”. But effects due to the proximity to the free surface would emerge in thinner films, below 50 nm or so, and this could cause some interesting phenomenon because the surface effect is counter to the “thickness effect”.

Problems have been encountered in the manufacture of shoe components from compounds based on Styrene-Butadiene-Styrene (SBS) block copolymers. These have included: adhesion pucker of the surface on bending; poor mar resistance; weld lines on appropriate mouldings; reduction in stiffness on mechanical working; and variable hardness with different processing conditions.

This thesis reports the development of a commercially viable, static dissipative,aerospace matt black polyurethane coating. A sheet resistance of 10 k/sq wasachieved with a loading level of 1.0 wt. % MWNTs, with electrical percolation atapproximately 0.3 wt. %.The characterisation of MWNTs available in commercially quantities above 1 kgis presented with key differences in agglomerate structure identified by scanningelectron microscopy (SEM) related to the synthesis method and the catalyst andcatalyst support used as identified energy dispersive X-ray spectroscopy (EDX). Atightening of the MWNT agglomerates after post processing such as purification,functionalisation and shortening is shown by SEM and confirmed using gas adsorp-tion and pore size distributions (PSDs).A scalable dispersion method based on probe sonication used to create 500 ml batchdispersions of MWNTs in organic solvents currently used in the coatings industryusing commercial high molecular weight dispersants. The required loading level wasdetermined using a stability check and related back to the specific surface area (SSA)obtained using the Brunauer–Emmett–Teller (BET) method. Changes in rheologyof the dispersions during sonication are related to the dispersion process using SEM.The compatibility of the MWNT dispersions when mixed with a commercial coatingresin are presented, and the onset of thixotropic behaviour, used to identify therheological percolation loading level. Standard coating tests confirmed the dry film properties of the coating are not ad-versely affected by the inclusion of the MWNT dispersions. It is shown that MWNTflocculation formed during mixing is broken during spray application but that floccu-lation also occurs during coating curing; un-pigmented systems being more severelyaffected than pigmented systems and higher curing temperatures and shorter timesbetween application and curing limiting the increase in sheet resistance.

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