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The aim of this Thesis work was to address the issue of microbial contamination inside fuel tanks. Microorganisms induce the chemical corrosion of airplane tank walls due to their production of organic acids. Biocide compounds are typically used to inhibit these microorganisms, either in the form of organic small molecules, or most commonly as chromium-based coatings on the walls to hinder chemical corrosion. Organic biocides need to be replenished regularly, while chromium is a particularly dangerous compound targeted by the European Registration, Evaluation and Authorization of Chemicals (REACh) legislation due to its carcinogenic nature. A replacement approach selected for this project was the development of a smart system of multifunctional polymeric particles synthesized by dispersion ROMP, which can deliver a biocide following an acidic trigger due to the presence of microorganisms. The polymerization utilized a linear α-norbornenyl-polyglycidol macromonomer as a reactive surfactant. The hydroxyl-rich polyglycidol backbone of the macromonomer was beneficial for the conjugation of dodecylamine through a pH-sensitive imine bond and permitted the preparation of highly functionalized bioactive particles. A proof of concept for the pH sensitivity of the system was provided and the antifungal efficacy of the biocide-functionalized macromonomer and particles was verified. The particles were also integrated in a coating formulation to simulate their application on tank walls. The qualities of the original coating were preserved even after prolonged exposure to corrosive conditions, making this system viable for its foreseen application., Ce travail de thèse consiste à combattre le développement microbien des réservoirs de carburant aéronautiques dont le métabolisme entraine la production d’acides organiques susceptibles de corroder les parois métalliques des réservoirs. Des substances biocides sont habituellement utilisées pour éliminer les populations microbiennes. Ces substances peuvent être des composés organiques ou bien de manière plus courante du chrome (VI) sous forme de revêtement à la surface des parois afin de créer une couche passive et d’empêcher la corrosion chimique. Cependant, le chrome appartient à la catégorie des substances cancérogènes, mutagènes et reprotoxiques et se trouve maintenant soumis à restriction par la réglementation européenne Registration, Evaluation and Authorization of Chemicals (REACh). Pour remplacer les systèmes en place, le choix s’est porté sur la préparation de particules polymères pH-sensibles capables de libérer une molécule biocide en présence de microorganismes. De telles particules sont obtenues par copolymérisation par métathèse de cyclo-oléfines (ROMP) de norbornène avec un macromonomère linéaire de polyglycidol α-norbornenyl. Ce dernier permet d’une part la stabilisation des particules et d’autre part la multifonctionnalisation de l’objet par des molécules de biocide. Celles-ci sont introduites sur la chaîne de polyglycidol via un lien imine pH-sensible par substitution des fonctions hydroxyle par des entités dodécylamine. La libération du biocide à un pH inférieur à 7 a été validée ainsi que les capacités de ces particules à lutter contre des microorganismes tel que Hormoconis resinae souche identifiée comme se développant dans les réservoirs d’avions. Dans une dernière étape, les particules fonctionnalisées dodécylamine ont été incorporées dans un revêtement usuel en aéronautique et la capacité des particules à ne pas altérer la résistance du revêtement de base à des conditions de corrosion extrêmes a permis de vérifier leur applicabilité dans ce domaine.

International audience; Dispersion Ring-Opening Metathesis Polymerization (ROMP) of norbornene (Nb) in the presence of a hydrophilic alpha-norbornenyl-polyglycidol macromonomer is a powerful method to obtain stabilized polymeric core-shell nanoparticles (NPs). Thanks to their high hydroxyl functionality content, one for every structural unit along the chain, the polyglycidol-based NPs can be viewed as plurifunctional platforms for the attachment of active molecules. The synthesis of polyglycidol macromonomers by anionic polymerization and their copolymerization with norbornene to give the NPs is described in the first part of this paper. In the second part, we take advantage of the presence of the hydroxyl groups to synthesize NPs with a high functionalization capacity. Dodecylamine, a primary amine known for its biocidal properties was selected as a model molecule and conjugated to the polyglycidol chains using a pH-sensitive imine bond. (C) 2016 Elsevier B.V. All rights reserved.

The aim of this work was to proceed to the design of new hyperbranched structures through the synthesis of glycidol-based polymers which can be used in the development of biodegradable copolymers, functional macromonomers and biocompatible magnetic nanocomposites. The first part of this work was the synthesis of hyperbranched macromonomer initiated by hydroxyethyl methacrylate (HEMA), hydroxyethyl acrylate (HEA) and polyethylene glycol methacrylate (PEGMA), through the study of the synthesis of polyglycerol (PG) by anionic, anionic coordinated and cationic polymerization of glycidol. Synthesis of poly (ε-caprolactone) macromonomers in the presence of various catalyst systems and initiators was also investigated. This part ends by the synthesis of dendrigrafts derived from the copolymerization of the macromonomers, by free radical polymerization or by controlled radical polymerization. The 2nd part of this work has been devoted to the synthesis of hyperbranched biocompatible copolymers obtained by random copolymerization of glycidol with ε-caprolactone in order to obtain hydrolyzable copolymers. The impact of the structure of the copolymers on their physico-chemical properties was then investigated. The biodegradable behavior of these polymers was then investigated through different enzymatic degradation tests. Finally, this work was focused on the development of biocompatible magnetic nanocomposites by the synthesis of magnetic nanoparticles and the immobilization of linear or hyperbranched polymers on their surface by different chemical grafting methods.; L’objectif de ce travail a été de procéder au design de nouvelles structures hyperramifiées en procédant à la synthèse de polymères à base de glycidol utilisables dans l’élaboration de copolymères biodégradables, de macromonomères fonctionnels et de nanocomposites magnétiques biocompatibles. Une première partie de ces travaux s’est intéressée, à la synthèse de macromonomères hyperramifiés amorcés par l’hydroxyéthyle méthacrylate (HEMA), l’hydroxyéthyle acrylate (HEA) et le polyéthylène glycol méthacrylate (PEGMA), par polymérisation anionique, anionique coordinée ou cationique du glycidol. La synthèse de macromonomères poly(ε-caprolactone) en présence de différents systèmes catalytiques et amorceurs a également été investiguée. Cette partie se termine par la synthèse de dendrigrafts issus de la polymérisation de ces macromonomères, par voie radicalaire classique ou contrôlée (RAFT/ATRP). La seconde partie de ce travail a été consacrée à la synthèse de copolymères hyperramifiés biocompatibles obtenus par copolymérisation statistique du glycidol en présence d’ε-caprolactone, en vu de l’obtention de copolymères hydrolysables. L’impact de la structure sur les propriétés physico-chimiques des copolymères obtenus a été étudié. Enfin, le caractère biodégradable de ces polymères a été investigué à travers différents tests de dégradation enzymatique. Enfin, ce travail s’est focalisé sur l’élaboration de nanocomposites magnétiques biocompatibles par la synthèse de nanoparticules magnétiques, puis l’immobilisation de polymères linéaires ou hyperramifiés à leur surface selon différentes méthodes de greffage chimique.

In contrast to their (oxa)norbornenyl counterparts, cyclobutenyl derivatives have remained relatively unexplored in ring-opening metathesis polymerization (ROMP), despite ROMP of cyclobutene derivatives yields unsaturated polymers based on a strictly 1,4-polybutadiene backbone that is not easily attainable by other routes. This article summarizes work done in our group in the field of cyclobutenyl-capped macromonomers that are convenient building blocks for the synthesis of graft (bottle-brush) copolymers by ROMP via the so-called macromonomer (or grafting-through) route. Synthetic strategies employing orthogonal chemistries such as reversible deactivation radical polymerization techniques (atom transfer radical polymerization – ATRP, and reversible addition-fragmentation chain transfert (RAFT) polymerization) and recent developments using copper-catalyzed azide–alkyne cycloaddition click chemistry are highlighted. Furthermore, ROMP of the so-obtained macromonomers, including preliminary novel results regarding ROMP of cyclobutenyl-capped macromonomers prepared through RAFT polymerization and click chemistry are reported and discussed.

International audience; The synthesis and characterization of novel poly (CTFE-g-oligoEO) graft copolymers chlorotrifluoroethylene (CTFE) and ethylene oxide (EO)] are presented. First, vinyl ether monomers bearing oligo(EO) were prepared by transetherification of x-hydroxyoligo(EO) with ethyl vinyl ether catalyzed by a palladium complex in 70-84% yields. Two vinyl ethers of different molecular weights (three and 10 EO units) were thus obtained. Then, radical copolymerization of the above vinyl ethers with CTFE led to alternating poly(CTFE-alt- VE) copolymers that bore oligo(OE) side chains in satisfactory yields (65%). These original poly(CTFE-g-oligoEO) graft copolymers were characterized by 1H, 19F, and 13C NMR spectroscopy. Their molecular weights reached 19,000 g mol 1, and their thermal properties were investigated while their glass transition temperatures ranged between 42 and 36 C. Their thermogravimetric analyses under air showed decomposition temperatures of 270 C with 10% weight loss (Td,10%). These novel copolymers are of potential interest as polymer electrolytes in lithium ion batteries, showing room temperature conductivities ranging from 4.49 10 7 to 1.45 10 6 S cm 1 for unplasticized material.

International audience; The radical telomerization of vinylidene fluoride (VDF) with various chain transfer agents (methanol, dialkyl phosphonates, 1-iodoperfluoroalkanes) is presented. ) First, telomerization 1 involves a telogen or a transfer agent (X-Y), and one or more (n) molecules of a polymerizable compound M (called taxogen or monomer), under radical polymerization conditions, leading to X-(M)n-Y telomers, as follows: Various examples of telomerization of vinylidene fluoride, VDF (H2C=CF2) involving different X-Y transfer agents (hydroxylated, phosphonated, halogenated have been investigated. The kinetics of telomerization enabled us to assess the transfer constants to the telogens and an increasing series regarding the efficiency of these transfer agents is supplied, correlated with the bond dissociation energy of the cleavable bond of the telogens: CF3CH2OH

International audience; This review summarizes nearly 400 references (since 1990) intended to highlight directions on the synthesis of telechelic oligomers and macromonomers by radical techniques. This review first takes into account the recent developments in further conventional radical polymerizations, such as dead-end polymerization and also telomerization reactions. Among all the conventional radical polymerizations, addition–fragmentation transfer (AFT) polymerization realized a real breakthrough for the synthesis of telechelic oligomers and especially for macromonomers by coupling AFT with catalytic chain transfer. Then, surveys concerning telechelic oligomers and macromonomers prepared by living radical polymerizations are mentioned. Atom transfer radical polymerization, nitroxide-mediated polymerization, reversible addition–fragmentation chain transfer polymerization and also iodine transfer polymerization allow for accurate control of chain-end functionality, either a functional group or a double bond. Novel reactions like radical coupling of oligomers previously obtained by living radical polymerizations are enhanced.

The present work discusses first the homopolymerization of ω-allyl, ω-undecenyl or ω-vinylbenzyl polystyrene (PS) macromonomers in the presence of selected early or late transition metal catalysts. Homopolymerization degrees were found to depend on the type of catalyst, the terminal double bond, the polymerization temperature and the concentration of the various species. Higher molar masses were reached at low temperatures and low catalyst and cocatalyst concentrations. Best results were obtained with the constrained geometry catalyst (CGC)-Ti. The same PS macromonomers were copolymerized with ethylene in the presence of the VERSIPOLTM catalyst to design a new type of poly(ethylene) based graft copolymer. The macromonomer weight percent content decreases with increasing ethylene pressure whereas the molar mass of the copolymer increases with ethylene pressure. The PS macromonomer content as well as the molar mass of the copolymer can be still increased by using α,ω-difunctional PS macromonomers. The dilute solution and solid-state behavior of these copolymers were examined and compared to those of poly(ethylenes) prepared under the same conditions. Copyright © 2006 John Wiley & Sons, Ltd.