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There is no abstract available for this thesis.

This creative project was undertaken to determine the effectiveness and possible usefulness of a small, laboratory sized plastic blow molder. The design of this machine was similar to those units used in industry but fabricated on a much smaller scale.The blow molder was of the vertical extrusion type. It was actuated by a hydraulic cylinder, and the plastic was melted by means of electric heating bands.The extruded plastic parison was formed by two matching mold halves, and air introduced through a needle valve to expand the hot plastic to the shape of the mold cavity.

This creative project has investigated the engineering principles relative to the design and fabrication of both a blown tubular film extrusion die and an air ring. The study has also made a careful analysis of the equipment necessary to construct a blown tubular film extrusion line.In addition, the creative project has discussed the origins of film extrusion, alternate methods of producing polyolefin films, and troubleshooting suggestions which can provide valuable assistance in the production of quality blown tubular film.

This creative project involved an in-depth study of the transfer molding process and the engineering and fabrication procedures related to the development of a hand transfer mold. The investigator made a study of and constructed the equipment required for transfer molding a knife handle.The creative project outlines the compression molding process, describes the variations of the transfer molding process, and lists and compares the advantages and disadvantages of the compression and transfer molding processes. The creative project also suggests a series of operating instructions that may be used with the transfer mold.

This creative project involved the design and construction of a plastics blow molding machine for educational use. Many industrial machines were found which performed plastics blow molding but studies revealed that no equipment had been designed particularly for school use.This project covered all elements of the design of a plastics blow molding machine concluding with the construction of a working model. In this process a complete set of working drawings was developed as illustrated in this paper.The operation of the machine proved successful but with evidence that improvements could be made.

No description available.

This work combines two technologically important areas of polymer science, namely polymer blends and fluoropolymers. New fluoroalkyl methacrylate polymers have been synthesised making use of the telomerisation of trifluoroethylene, to give a partially fluorinated sidechain on a methacrylate backbone. After characterisation, these materials were mixed with poly(methyl methacrylate), and the bulk phase behaviour and surface properties of these blends was investigated. Using differential scanning calorimetry and small angle neutron scattering, it has been established that these materials are in a state of incipient phase separation. Surface energetics of films of these blends have been investigated using contact angle measurements, and the near surface depth profile has been studied using neutron reflectivity and Rutherford backscattering spectrometry

This thesis describes the experimental investigations of the structural properties of the conductive polymer, poly aniline. These studies have been performed on free-standing film samples, solution cast using the solvent N- methyl-2-pyrrolidinone (NMP). Such specimens have enabled a wealth of detailed information about polyaniline to be derived. The polymer itself was synthesised in the emeraldine base form using a chemical route optimised at Durham. The product was then assessed for its chemical structure and molecular weight using (^13)c NMR, elemental analysis and gel permeation chromatography. The process of fabricating the polymer into free-standing films is discussed and assessed. It has been shown that such films may be oriented by the application of uniaxial stress at elevated temperatures and this procedure has been described and analysed in detail. This stretching process aligns the polymer chains on a molecular level and hence produces changes in the physical properties of films. In particular, upon doping to the conducting emeraldine salt form by protonation in aqueous HCl, stretch oriented films display a remarkable increase in conductivity (parallel to the stretch direction) over their unstretched, doped counterparts. Various thermal analysis techniques, including dynamic mechanical thermal analysis, dielectric thermal analysis, thermomechanical analysis and infrared spectroscopy have been used to probe the physical properties of polyaniline films. Using these techniques a number of important thermal transitions have been observed and furthermore the stretch alignment process has been rationalised. Infrared orientational analysis has revealed detailed information about the molecular orientation produced during macroscopic stretching of a film. The type and degree of chain orientation has been analysed as well as the geometrical structure of a single chain. X-ray diffraction has probed the crystalline fraction of polyaniline films. Various aspects concerning the crystalline fraction of film samples has been derived along with an orientational analysis which has been contrasted with the infrared results. An even greater amount of structural information has been revealed by neutron diffraction and this technique has enabled a detailed examination of the structure of the crystalline phases of polyaniline to be made.