Amine bis(phenolate) ligands synthesis can be easily prepared by the reaction of a substituted 2-(bromomethyl)phenol, a substituted phenol, potassium carbonate, triethylamine and the appropriate amine to form the desired compounds in high yields and purities. A series of amine bis(phenolate) ligand precursors with group 4 metals and aluminum complexes have been prepared, characterized by single-crystal X-ray diffraction, and tested for ring opening polymerisation of £`-caprolactone. Group 4 metals complexes which are shown to be active catalysts for the ROP of £`-caprolactone with excellent conversions and polydispersities. All aluminum compounds as four-coordinate aluminum methyl complexes show excellent catalytic activity toward the ring opening polymerization of £`-caprolactone in the presence of benzyl alcohol. And amine bis(phenolate)s ligand ([tert-ButylONO]2-) bond cleavage with zirconium and hafnium complexes that have been prepared, characterized by single-crystal X-ray diffraction. Another zirconium complexes of dianionic amine bis(phenolate) ligands have been synthesized, their X-ray structures solved, and their activity as 1-hexene polymerization catalysts study. Upon treatment with B(C6F5)3, a series of pentacoordinate [ONO]Zr(CH2Ph)2 complex, having no extra donor group, shows only poor activity as a polymerization catalyst. Final reaction of diamine-bis(phenol) ligands containing a mixture of [i-PropylONO]Ti(OiPr)2 in dry THF under RT without exclusion of air and moisture gives {[i-PropylONO]TiO}3 (characterised by X-ray crystallography) is hydrolysed with H2O.

ABSTRACT BIOSENSOR BASED ON INTERPENETRATED POLYMER NETWORK OF ALGINIC ACID AND POLY (1-VINYLIMIDAZOLE) Kartal, M&uuml / jgan M.S., Department of Chemistry Supervisor : Prof. Dr. Levent Toppare January 2008, 63 pages A new proton conductor polymer was prepared using alginic acid (AA) and poly (1-vinylimidazole) (PVI). The polymer network was obtained by mixing AA and PVI at various stoichiometric ratios, x (molar ratio of the monomer repeat units). The AA/PVI network was characterized by elemental analysis (EA) and FT-IR spectroscopy. Potential use of this network in enzyme immobilization was studied. Enzyme entrapped polymer networks (EEPN) were produced by immobilizing invertase and tyrosinase (PPO) in the AA/PVI network. Additionally, the maximum reaction rate (Vmax) and Michaelis-Menten constant (Km) were investigated for the immobilized invertase and enzymes. Also, temperature and pH optimization, operational stability and shelf life of the polymer network were examined.

Cette thèse porte sur l'inter relation entre la superstructure moléculaire, les propriétés et la dégradabilité du poly butène isotactique. L'évolution la plus importante est une transformation de phase particulière de la forme cristalline II à la forme cristalline I après cristallisation du polymère à partir de l'état fondu. Cette transformation a été caractérisée par calorimétrie, par diffraction des rayons X aux grands angles et par l'analyse des propriétés mécaniques en fonction des conditions de thermique de recuit. L'effet de la mise en forme sur la superstructure résultante a été mis en évidence sur des échantillons obtenus par injection ou par extrusion en utilisation les propriétés mécaniques en traction. Du fait de la très grande sensibilité du PB-1 vis-à-vis de la photodégradation des effets significatifs sur les propriétés thermiques et sur la transformation de phase ont été observés. Une caractérisation multi-échelle en photodégradation a été réalisée à partir d'analyses calorimétriques, d'analyse en spectroscopie infrarouge, de la diffraction des rayons X et des propriétés mécaniques en traction et ceci tant en photovieillissement en conditions accélérées qu'en conditions d'exposition naturelle.

Langmuir-monolayer formation at the air/water interface (A/W) can be achieved by spreading amphiphilic molecules on a liquid subphase and compressing them into an ordered arrangement. The use of the Langmuir-Blodgett technique (LB) to prepare ultra thin films on solid surfaces from monolayers at A/W has considerable utility for studying surface interactions. In particular, the phase behavior of polyhedral oligomeric silsesquioxanes (POSS) was examined using a combination of LB and Brewster angle microscopy (BAM).Polymer fillers have been shown to reduce the cost and often improve the properties of high performance polymer composites. The utility of POSS as a potential nanofiller in blends with polymers such as poly(dimethylsiloxane) (PDMS) and poly(vinylacetate) (PVAc) was explored using surface pressure-area per monomer isotherms (P-A) and BAM. Substantial morphological differences are seen between polymer blends with heptasubstituted trisilanol-POSS and fully condensed octasubstituted-POSS due to differences in subphase affinity.Several poly(1-alkene-alt-maleic anhydride) (PXcMA) polymers were studied at both the gas/liquid interface as Langmuir films and at the gas/solid interface as Langmuir-Blodgett thin films on silicon substrates. A 0.01 M HCl solution (pH~2) was used during film deposition to ensure the carboxylic acids were fully protonated. The PXcMA polymers included X=1-hexene, 1-octene, 1-decene, and 1-octadecene (represented as PHcMA, POcMA, PDcMA, and PODcMA respectively). The P-A isotherms of these polymers were consistent with those obtained previously.1Tensiometry was used to determine the critical micelle concentrations (c.m.c.) of variable molar mass poly(dimethylsiloxane-b-(3-cyanopropyl)methylsiloxane-b-dimethylsiloxane) (PDMS-PCPMS-PDMS) triblock copolymers and a poly(dimethylsiloxane-b-2-ethyl-2-oxazoline) diblock copolymer. Dynamic light scattering (DLS) corroborated interfacial tension results. The polymers exhibited well-defined temperature-independent c.m.c.'s. These measurements ensured that the synthesis of cobalt nanoparticles for biocompatible magnetic fluids occurred above the c.m.c. / Master of Science

This dissertation discusses the polymorphism, crystallization and melting behavior of propylene-ethylene random copolymers. It also discusses the results of studies of the miscibility and the competitive liquid-liquid demixing and crystallization processes in blends of poly(propylene) and poly(1-butene). In the first part of this study, polymorphism of propylene-ethylene copolymers is studied by wide angle X-ray diffraction. By comparing the a and y crystal phase contents in samples with different ethylene content as well as samples isothermally crystallized at different temperatures, it was shown that increasing ethylene content as well as increasing crystallization temperature promotes the formation of the y-phase. Comparison of the results from fractionated samples and unfractionated samples with similar ethylene contents reveals that in propylene-ethylene copolymers with similar micro-structure, the polymorphism, crystallization and melting behavior are mainly determined by their ethylene content. The issue of co-unit inclusion and its effect on crystallization and melting behavior are also discussed. In the second part of this dissertation, the miscibility behavior of atactic - poly(propylene) (at-PP) and atactic poly(1-butene) (ai-P1B) with different molecular weights is investigated by differential scanning calorimetry. The phase diagram of at-PP and at-P1B blend of molecular weight (87K/48.5K) shows a upper critical solution temperature (UCST) behavior. The UCST behavior is consistent with predictions by the group contribution method. Miscibility behavior of high molecular weight isotactic poly(propylene) (it-PP) and isotactic poly(1-butene) (it-P1B) blend is investigated by a combination of optical microscopy and scanning electron microscopy, differential scanning calorimetry and dynamic mechanical analysis. These studies reveal that for the molecular weights investigated, it-PP and it-P1B form blends that are partially miscible in the liquid state. Liquid-liquid demixing is observed by optical microscopy at temperatures above the melting temperature of the it-PP component and is also inferred from scanning electron micrographs of the freeze fracture surface of quenched blends after extraction of the it- P1B component with cyclohexane. It-PP spherulites grow through both liquid phases at relative rates that depend markedly on the crystallization temperature. The complex multiple-melting behavior of the it-PP component in the blend is explained in terms of a bimodal distribution of it-PP lamellar crystals which result from crystal growth in the phase-separated liquid. Finally, the dynamic mechanical analysis data are explained in terms of a liquid-liquid demixing process that results in a significant degree of phase mixing. / Ph. D.

Synthetic and degradable polymers are an attractive choicein many areas, since it is possible to control the way in whichthey are manufactured; more specifically, pathways tomanipulate the architecture, the mechanical properties and thedegradation times have been identified. In this work,L-lactide, 1,5-dioxepan-2-one and ε-caprolactone were usedas monomers to synthesize polymers with different architecturesby ring-opening polymerization. By using novel initiators,triblock copolymers, functionalized linear macromonomers andstar-shaped aliphatic polyesters with well-defined structureshave been synthesized. To synthesize triblock copolymers,cyclic germanium initiators were studied. The polymerizationproceeded in a controlled manner although the reaction rateswere low. To introduce functionality into the polymer backbone,functionalized cyclic tin alkoxides were prepared and used asinitiators. During the insertion-coordination polymerization,the initiator fragment consisting mainly of a double bond wasincorporated into the polymer backbone. The double bond wasalso successfully epoxidized and this gave unique possibilitiesof synthesizing graft polymers with precise spacing. Themacromonomer technique is a very effective method for producingwell-defined graft polymers. Spirocyclic tin initiators weresynthesized and used to construct star-shaped polymers. Thestar-shaped polymers were subsequently crosslinked in apolycondensation reaction. These crosslinked structures swelledin water, and swelling tests showed that by changing thestructure of the hydrogel network, the degree of swelling canbe altered. A first evaluation of the surface characteristicsof the linear triblock copolymers was also performed. AFManalysis of the heat-treated surfaces revealed nanometer-scalefibers and tests showed that keratinocytes were able to growand proliferate on these surfaces. / QC 20100602

Conductive polymers are also known as "organic metals" due to their semiconducting properties. They are found in a wide range of applications in the field of organic electronics. However, the growing number of experimental works is not widely supported with theoretical calculations. Hence, the field of conductive polymers is experiencing lack of understanding of mechanisms occurring in the polymers. In this PhD thesis, the aim is to increase understanding of conductive polymers by performing theoretical calculations.        The polymers poly(3,4-ethylenedioxythiophene) (PEDOT) together with its selenium (PEDOS) and tellurium (PEDOTe) derivatives, poly(p-phenylene) (PPP) and naphthobischalcogenadiazoles (NXz) were studied. Several computational methods were applied for analysis of mentioned structures, including density functional theory (DFT), tight-binding modelling (TB), and Car-Parrinello molecular dynamics (CPMD) calculations. The combination of CPMD and DFT calculations was applied to investigate the PEDOT, PEDOS and PEDOTe. The polymers were studied using four different functionals in order to investigate the full picture of structural changes, electronic and optical properties. Temperature effects were studied using molecular dynamics simulations. Wide statistics for structural and molecular orbitals analysis were collected.         The TB method was employed for PPP. The formation and motion of the excitations, polarons and bipolarons, along the polymer backbone was investigated in presence of electric and magnetic fields. The influence of non-magnetic and magnetic impurities was determined.        The extended π-conjugated structures of NXz were computed using B3LYP and ωB97XD functionals in combination with the 6-31+G(d) basis set. Here, the structural changes caused by polaron formation were analyzed. The combined analysis of densities of states and absorption spectra was used for understanding of the charge transition. / <p>QC 20170928</p>