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A detailed study of the effect of polyester resin structural parameters on the mechanical properties of sheet moulding compounds has been carried out. The investigation involved the synthesis and mechanical testing of a series of unsaturated polyester resins and the incorporation of these resins into sheet moulding compounds (SMC) with their subsequent testing. Two main structural parameters were varied, firstly the degree of unsaturation of the resin (i.e. maleic:phthalic ratio), and secondly the amount of diol excess added to the reaction vessel during the resin synthesis thereby varying the hydroxyl value of the resin. It was found that the properties of the resins, both structural and mechanical, were interdependent. Altering the maleic:phthalic ratio was found to effect the hydroxyl value, notch sensitivity, shrinkage, and modulus of the resin. Low resin hydroxyl values were found to give SMC with low tensile strength and low fracture toughness. Unusually high hydroxyl values enhanced the toughness but the SMC did not show the expected increase in tensile strength. Surprisingly the toughness of SMC appears insensitive to the notch sensitivity of the resins despite the relatively wide range of resins used and their range of notch sensitivities. It was concluded that debonding was the predominant mechanism by which failure occurred in these composites and that the bond strength was enhanced by the use of a matrix resin with a suitably high hydroxyl value. A high hydroxyl value being dependent on the dial excess and the maleic:phthalic ratio of the resin.

The aim of this thesis was to develop and process viable rubber-thermoplastics blends from ground tyre rubber (GTR) and waste polypropylene (WPP). The use of WPP with waste rubber in blends is novel, although limited studies have been carried out on virgin polypropylene (PP)-waste rubber blends. The Delink pretreatment for the GTR is also a novel technique used for property enhancement. To achieve the aim, a number of GTR/WPP blends were prepared, in different blend compositions (from 0 to 100 wt% of each polymer), at different processing parameters, and with two compatibilizing systems. One system called dimaleimide contained N-N' meta-phenylene dimaleimide (HVA-2) as the compatibilizer and either di(tert-butylperoxyisopropyl) benzene (DTBPIB) or 2-2'-dithiobenzothiazole (MBTS) as an activator. The other system contained phenolic resin compatibilizer (SP 1045H resin) and stannous chloride (SnCl2) activator in two forms: anhydrous and dihydrated. The compatibilizer level varied from 0 to 5 pphp, while the activator level varied from 0 to 1 pphp.

The aim of this thesis is to study the effect of precipitated calcium carbonate (pcc) on the processing behaviour, morphology and mechanical properties of both rigid and cellular PVC. To do this, a number of different grades of pcc have been examined and the effects explained with respect to the particle size, shape and surface coating of the different grades. An important part of the novelty of this work has been the study of pcc grades in PVC stabilised with more environmentally friendly mixed metal (calcium/zinc) stabilizers. They are becoming increasingly important because the PVC industry in Western Europe is committed to phase out lead stabilizers by the year 2015.

The overall aim of this research is to develop unique conducting polyaniline (PANI) membranes that can be electrically tuned to achieve different fluxes and selectivity. The target application is in a tuneable membrane reactor, where these membranes allow the fouling layer to be pushed off/through membranes by application of external potential. To achieve this, several different types of PANI membranes were examined. The permeation properties of HCl-doped PANI membranes can be modified electrically to produce in-situ tuneable separations. However, acid dopant leaching and membrane brittleness limit the further application of these membranes. Polymer acid doped PANI membranes using poly(2-acrylamido-2-methyl-1-propanesulfonic acid) or PAMPSA were investigated as a solution. These PAMPSA doped PANI membranes displayed improved mechanical strength and filtration stability. However, the membranes showed decreased electrical conductivity, leading to a limited tuneable permeance and selectivity under applied potential. To overcome this new challenge, expanded graphite and a large acid (dodecylbenzene sulfonic acid or DBSA) were incorporated into the PAMPSA doped PANI membranes to increase the conductivity. Despite increasing both conductivity and electrical tuneability, the resulting membranes were more porous with looser molecular weight cut-off (outside of the desired NF/low UF MWCO range) than without modification. Efforts to tighten PAMPSA doped membranes to the same MWCO as HCl doped membranes using volatile co-solvents (THF and acetone) were unsuccessful: porosity was due to the large acid dopants. Membranes were examined for their potential for in-situ fouling removal of model foulant bovine serum albumin under applied voltage. This was successful and defouling extent was found to be closely related to membranes with higher conductivity and greater acid stability. Overall, it has been demonstrated that the conducting polyaniline composite membranes can be made to be stable to acid leaching and be more mechanically robust, whilst also being externally electrically tuned to different molecular selectivities with the potential for in-situ fouling control.

A study of creep at temperatures within the rubbery plateau region is presented. Creep and stress-relaxation are reviewed and such relevant factors as crystallisation and surface cracking during creep are considered. Creep is determined by both physical (viscoelastic) and chemical mechanisms. "physical creep" is manifested by semi-logarithmic, creep log (time), or log-log kinetics whereas ''chemical creep" follovrs a generally linear law, creep time. These relationships are examined in terms of their relevance to data extrapolation beyond the experimental time scale. The semi-logarithmic relationship implies that the apparent activation energy for creep increases in proportion to creep strain and a tentative explanation of why this may be so is suggested. It is considered that such creep kinetics may be attributed to the slow breakdown and re-organisation of regions of short range order in the rubber. This activation energy approach is used to interelate creep data with tensile stress-strain data at different strain rates. The physical creep of carbon black filled vulcan-izates did not follow semi-logarithmic kinetics except at short times.

Chemically modified polyaniline (CMP) self doped derivatives were synthesised by the diazotisation of polyaniline, copolyanilines and polyaniline-Ti02 nanoparticle composites with diazonium salts and polymerising aniline diazo anilic or anthranilic dyes. Oxidative chemical polymerisation in strong acidic aqueous media with the help of (NH4)2S20a was employed to polymerise monomers or comonomers. The diazotisation of polyanilines was proved to be the most promising and efficient to incorporate sulphonic phenyl groups in polyanilines structure to form self doped CMPs. The highest degree of self doping! suiphonation was achieved when polyaniline- Ti02 composites were coupled with diazonium ion. CMPs were investigated with the help of analytical techniques such as UVVis, FT-IR, FT-NMR, fluorescence and elemental analysis. The spectroscopic and physical data confirm the introduction of chemically linked sulphonic phenyl groups and formation of triphenyl amine like fluorophores structures in them. They have the fundamental polyaniline properties as they are green in acidic and blue in basic media, pH sensitive, have reversible electrochromic and redox behaviour in different environments. They are highly fluorescent, soluble in polar solvents (H20, R-OH, NMP, DMSO, DMF) and optical metals ion sensor. Their solutions have persistent fluorescence even after several months without significant changes in their spectra. They can be immobilised directly and in the form of composites with other reagents such as PMMA, PVA, nafion and sol gel on glass and polymeric substrates. Their composite films are stable in ambient conditions and luminescent even after a period of one year. Their solubility, fluorescence and optical metals ion sensing are directly related to their degree of sulphonation! self doping. Consequently, SPPATi02 has better solubility, higher fluorescence intensity, stable optical pH response and lower limit of detection for Cu2+ ion compared to that of SPPA and SPCPA. Their UV-Vis absorption and emission spectra are pH sensitive with a linear and quick optical response in the range of pH 5-8. They have excitations at 256-258 and 292-300 nm in acidic and basic media respectively while emissions at 423- 428nm. They have broad optimum pH ranges (pH 6-10) for their emission and metal ions sensing. They can be used as pH sensor for a broad range of pH 3-8, out of which the optical sensitivity of pH 3-6 is based on hypo! hyper chromic effects in their fluorescence while of pH 5-8 in their UV-Vis absorption spectra. They are optical metals ions sensors for higher concentrations (> 10-4M) of heavy metals ion but are selective and sensitive to Cu2+ ion «10-4 M) lower concentrations. The optimum pH ranges for their optical Cu2+ ion sensing are broad (pH 6-10). Their LOO and LOa for Cu2+ ion on the basis of fluorescence quenching are in the ranges 3.96 x 10-7 - 4.5 x 10-7 and 1.3 x 10-6 - 1.5 x 10-6M respectively.

This thesis describes the preparation of the polymer of intrinsic microporosity PIM-7 by heterogeneous polymerisation and explores its application in the fields of electro less copper deposition and inkjet technology. The effect of polymerisation conditions (such as the concentration and ratio of the monomers, the presence of base and co-catalyst and the duration of polymerisation) on polymer molar mass was explored. The results were compared with the respective ones in the case of PIM-l. Further, the possibility of using PIMs, loaded with Pd2+, as catalysts of electroless copper deposition was examined. The efficiency of the type of PIM used, type and concentration of palladium salt, duration of palladium loading, reduction step, and duration of metallization were examined, aiming at achieving a nice copper deposit in the minimum time. The rheology of PIMs was briefly explored in order to determine their intrinsic viscosity and response to shear strain. Both experiments showed that PIMs behave differently from most polymers due to their stiff and bended chain structure and its inability to change conformations. Finally, solutions of PIMs in a non-volatile solvent were used as inks for inkjet printing. The effect of molar mass and concentration of the polymer, as well as the effect of the pulse voltage and frequency on the drop formation, ligament length and ligament lifetime were determined.