This work details the properties of a copolymer system comprising the ethylenedioxythiophene (EDOT) and bithiophene (BT) monomers. By applying a number of characterisation techniques to various aspects of the copolymer system an insight into its behaviour during redox cycling has been gained. If a copolymer is grown from a feed solution containing two different monomers, the mole fraction of monomers in the resulting copolymer will be determined by the composition of the feed solution and the relative reactivities of the two monomers. Only a small range of feed solutions yield copolymers containing substantial amounts of both components, except for pairs of monomers having very similar reactivities X-ray Photoelectron Spectroscopy (XPS) was introduced as a technique to determine the mole fraction of monomers within a copolymer film and compared with the mole fraction of the feed solution.

Particles containing 55% divinylbenzene (DVB) have been prepared using dispersion polymerisation. The steric stabilisers that have been utilised are partially hydrolysed poly(vinyl acetate)s, poly(ethylene oxide) and a poly(ethylene oxide) macromonomer in methanolic media. The concentrations of stabiliser, monomer and initiator have been varied to investigate the influence that they have on the particle size and the particle size distribution. The particles have been characterised by scanning electron microscopy (SEM) for a visual impression of the particles in addition to laser diffraction particle size analysis and hydrodynamic chromatography (HDC) for particle size.

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The syntheses of aromatic oxazolyl functionalized chain end polystyrene and poly(methyl methacrylate) using an oxazolyl functionalized initiator in atom transfer radical polymerization were effected by the following methods: The synthesis of 2-[(4-bromomethyl)phenyl]-4,5-dihydro-4,4-dimethyloxazole from α-bromo-р-toluic acid. The preparation of well defined α-oxazolyl functionalized polymers using 2-[(4-bromomethyl)phenyl]-4,5-dihydro-4,4-dimethyloxazole as an oxazolyl functionalized initiator for the atom transfer radical polymerization of styrene and methyl methacrylate in the presence of copper(I)bromide /2,2'-bipyridine or copper (I) bromide/N,N,N',N",N"-pentamethyldiethylenetriamine catalyst system at temperature ranging between 90 °C-110 °C. / Chemistry / Ph.D. (Chemistry)

Les technologies en perpétuelle évolution exigent des matériaux nouveaux, performants et plus spécialisés avec des fonctions hautement spécialisées. De tels matériaux ne sont plus des systèmes a un seul composant. Les systèmes qui font l’objet de l’investigation, les copolymères chimiquement réticulés de type "isobornyl acrylate-co-isobutyl acrylate" (IBOA-co-IsoBA), ont été préparés par photopolymérisation/réticulation sous rayonnement UV-visible des deux monomères IBOA et IsoBA en présence d'un agent de réticulation di-fonctionnel et d'un photoamorceur. Dans ce travail les propriétés thermiques et mécaniques ont été étudiées par calorimétrie différentielle à balayage (DSC), analyse mécanique dynamique (DMA) et analyse thermogravimétrique (ATG). Nous avons constaté par l’analyse calorimétrique (DSC) que la modification de la concentration d’agent réticulant, la quantité des monomères, et la vitesse de la rampe de chauffage influent notamment sur la température de transition vitreuse Tg : Une augmentation de ces paramètres provoque une augmentation de la température de transition vitreuse du copolymère. L’analyse thermogravimétrique par ATG montre que la dégradation du copolymère se fait en deux étapes, et que l’augmentation de la quantité de l’IsoBA diminue la température de dégradation du copolymère. L’étude des copolymères de type (IBA-co-IsoBA) par DMA a été entreprise en fonction de la fréquence et de la température, afin d’évaluer les modules d’élasticité (E’) et de perte (E’’). Une courbe maitresse (master curve) a été obtenue à l’aide du principe de superposition temps-température. Des modélisations des relaxations mécaniques ont été effectuées en appliquant les modèles d’Arrhenius, Cole-Cole, WLF et de VFT (Vogel Fulcher Tamman). / Ever-changing technologies require new, high-performance and more specialized materials with highly specialized functions. Such materials are no longer one-component systems. The systems which are the subject of the investigation, the chemically crosslinked copolymers of the "isobornyl acrylate-co-isobutyl acrylate" type (IBOA-co-IsoBA), were prepared by photopolymerization / crosslinking under UV-visible radiation of the two monomers. IBOA and IsoBA in the presence of a di-functional crosslinking agent and a photoinitiator. In this work the thermal and mechanical properties were studied by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA).We have found by calorimetric analysis (DSC) that the modification of the concentration of crosslinking agent, the amount of monomers, and the speed of the heating ramp affect, in particular, the glass transition temperature Tg: an increase of these parameters causes an increase in the glass transition temperature of the copolymer. Thermogravimetric analysis by (TGA) shows that the degradation of the copolymer occurs in two stages, and that the increase of the amount of IsoBA decreases the degradation temperature of the copolymer. The study of copolymers of type (IBA-co-IsoBA) by DMA was undertaken according to the frequency and the temperature, in order to evaluate the modulus of elasticity (E') and of loss (E''). A master curve has been obtained using the time-temperature superposition principle. Modeling of the mechanical relaxations was carried out by applying the models of Arrhenius, Cole-Cole, WLF and VFT (Vogel Fulcher Tamman).

The syntheses of aromatic oxazolyl functionalized chain end polystyrene and poly(methyl methacrylate) using an oxazolyl functionalized initiator in atom transfer radical polymerization were effected by the following methods: The synthesis of 2-[(4-bromomethyl)phenyl]-4,5-dihydro-4,4-dimethyloxazole from α-bromo-р-toluic acid. The preparation of well defined α-oxazolyl functionalized polymers using 2-[(4-bromomethyl)phenyl]-4,5-dihydro-4,4-dimethyloxazole as an oxazolyl functionalized initiator for the atom transfer radical polymerization of styrene and methyl methacrylate in the presence of copper(I)bromide /2,2'-bipyridine or copper (I) bromide/N,N,N',N",N"-pentamethyldiethylenetriamine catalyst system at temperature ranging between 90 °C-110 °C. / Chemistry / Ph.D. (Chemistry)

Several copolymers of linear polystyrene were prepared for evaluation as soluble polymeric supports for organic synthesis. These polymers were utilized for the synthesis of ?2-isoxazoline compounds. The target compounds were synthesized via 1,3-dipolar cycloaddition reactions between polymer bound alkenes and nitrile oxides generated in situ from their corresponding aldoximes. The cleaved ?2-isoxazoline compounds were tested for biological activity against Mycobacterium fortuitum. To compare the success of these linear polystyrene copolymers, some of the ?2-isoxazoline compounds synthesized on soluble polymeric supports were also prepared via traditional crosslinked polymer supports. The polymer-bound ?2-isoxazolines were also tested for antimicrobial activity. In addition attempts were made to prepare polymers containing the ?2-isoxazolines but anchored by non-hydrolysable bonds. Although the copolymers of polystyrene gave good loading capacity in mmol/g, and being soluble in chlorinated solvents it was possible to monitor the reactions by 1H NMR spectroscopy, the cleavage of the polymer bound products proved to be quite troublesome. Product purification was not as straightforward as it was anticipated. Isolation of the cleaved target compounds proved to be time consuming and laborious when compared to the traditional organic synthesis and solid phase organic synthesis (SPOS). Polymer-bound ?2-isoxazolines close to the polymer backbone exhibited some biological activity against Staphylococcus aureus. Polymers with substitution at the para-position of the aryl substituent at position 3 of isoxazoline ring showed antimicrobial activity.

L’athérosclérose est une maladie vasculaire dont les complications sont la première cause de mortalité dans les pays développés. Pour soigner cette pathologie, une des méthodes les plus employées est l’angioplastie couplée au stenting. Ce geste occasionne cependant de forts risques de complications postopératoires, dont la plus répandue est la resténose. Pour refreiner ce phénomène, différentes stratégie peuvent être exploitées, l’une d’elle consiste à immobilisé sur la surface du stent des composés bioactifs pour en faciliter l’acceptation par l’organisme. C’est dans ce contexte que s’inscrit cette étude. L’idée première est de fonctionnaliser le titane, métal couramment dans le domaine médical, par des polymères pouvant être modifiés en quantité désirée par des molécules bioactives.Pour atteindre cet objectif, nous avons employé la polymérisation radicalaire contrôlée. Cet outil de choix permet d’obtenir des polymères parfaitement définis comportant une fonctionnalité en extrémité de chaîne. Dans notre cas, nous avons choisi d’y fixer une ancre catéchol, molécule naturelle ayant une forte affinité avec le titane. Différents polymères ont été conçus et, après caractérisation, ont été immobilisés sur le titane pour former des brosses. Les surfaces ainsi obtenues ont été caractérisée en termes de composition et de densité de fonctionnalisation. Enfin nous avons employé une molécule test, la glucosamine, pour modifier en différentes quantités une plateforme polymère, puis d’évaluer biologiquement ces polymères en solution et immobilisés sur le titane pour en étudier l’influence sur différentes lignées de cellules. / Atherosclerosis is a vascular disease, whose complications are the first cause of death in developed countries. In order to cure this pathology, angioplasty, coordinated with stenting, is nowadays one of the most used treatment. However, postsurgical complications can often occur with this surgery technique. The frequency of restenosis, the most common complication, could be decreased thanks to different strategies. One of these strategies is to graft on stent surface bioactive molecules that enhance biocompatibility.In this context with have endeavored to functionalize titanium, commonly used in medical applications, with polymers that can bear bioactive molecules. In order to reach this goal, we used controlled radical polymerization, which can provide end-functionalized, well-defined polymers. In our case, we have chosen to craft polymers with a catechol at the chain end, a natural anchor which have good affinity with titanium. During this study, different kind of polymers have been built and analyzed. Then, they were grafted to titanium substrates to create polymer brushes. Grafting densities and surfaces compositions were characterized thanks to different techniques. Finally, we tried to modify a polymeric platform with different quantities of glucosamine, a test molecule. These polymers were then biologically evaluated alone and grafted to titanium with different cell lines.

La synthèse et l’étude de nouveaux oligoesters amphiphiles agro-sourcés et branchés à base d’acide succinique bio-sourcé, de glycérol, d’acides gras et d’autres synthons agro-sourcés ont été envisagées pour des applications tensioactives dans des domaines variés en remplacement des tensioactifs pétro-sourcés. La stratégie mise en place s’inscrit dans une démarche d'éco-conception visant à obtenir des propriétés organoleptiques acceptables ainsi que des propriétés physico-chimiques et fonctionnelles comparables à celles de composés de référence. Dans un premier temps, l’impact de la succinylation sur les propriétés physico-chimiques et fonctionnelles de tensioactifs non-ioniques a été étudié. Puis, des oligomères hydrophiles de poly(glycérol-acide succinique), PGS, non-toxiques et biodégradables, ont été synthétisés sans solvant ni catalyseur et caractérisés dans le but de développer de nouvelles têtes polaires bio-sourcées de tensioactifs. Des modèles mathématiques ont été développés à partir des données obtenues par RMN 13C quantitative afin d’extraire des informations structurales telles que le degré de polymérisation moyen en nombre.Dans un troisième temps, des oligomères d’acyles PGS ont également été préparés et étudiés. Il a ainsi été montré que les dérivés lauroyles forment des mousses abondantes et stables, présentent un large éventail de temps de mouillage et d'excellentes propriétés de solubilisation micellaire. Enfin, afin d’améliorer les propriétés physico-chimiques et fonctionnelles des lauroyles PGS obtenus par synthèses catalysées en augmentant l’homogénéité des mélanges réactionnels, des comonomères servant de solvants copolymérisables ont été utilisés. Dans le contexte d’une législation de plus en plus stricte, ce type de macromolécules biodégradables et bio-sourcées constitue une plate-forme prometteuse ouvrant la voie à d'autres modifications chimiques dans le but de cibler d'autres applications potentielles. / The synthesis and the study of new crop-sourced and branched amphiphilic oligoesters based on bio-sourced succinic acid, glycerol, fatty acids and other crop-sourced building blocks have considered for surfactive applications in various fields as substitutes for petrochemicals. The implemented strategy is part of an eco-design approach to obtain acceptable organoleptic, physico-chemical and functional properties comparable to those of benchmarks. At first, the impact of succinylation on the physico-chemical and functional properties of non-ionic surfactants derived from ethoxylated fatty alcohols, glycerol monolaurate and alkyl polyxylosides has been studied. In a second step, non-toxic and biodegradable poly(glycerol-succinic acid) oligomers, PGSs, were synthesized without solvent nor catalyst and characterized with the intention of developing new bio-sourced polar heads of surfactants. Mathematical models have been developed so as to extract the widest range of structural information such as the number-average degree of polymerization, DPn from the quantitative 13C NMR data. In the third phase, acyl poly(glycerol-succinic acid) oligomers or acyl PGSs were synthesized and studied. It has been shown that lauroyl derivatives form abundant and stable foams, exhibit a wide range of wetting powers and display excellent properties of micellar solubilization. Finally, to improve the physico-chemical and functional properties of the lauroyl PGSs obtained by catalyzed synthesis by increasing the homogeneity of the reaction mixtures, comonomers were used as copolymerizable solvents. Within the context of a tightening legislation, this type of bio-sourced macromolecules constitutes a promising platform paving the way for further chemical modifications and various grafting to target other potential applications.

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