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[No abstract available] / Science, Faculty of / Chemistry, Department of / Graduate

L’évolution des propriétés d’adhérence dépend de la nature de l’adhésion entre le mortier et son support, mais également des conditions environnementales auxquelles l’ouvrage est exposé. Les mortiers de façade sont intrinsèquement soumis au séchage. Ce phénomène tend a priori à réduire la résistance du lien entre les matériaux par la limitation du développement de l’adhésion et par la création de contraintes de traction et de cisaillement.Ces dernières peuvent conduire à la fissuration voire à la désolidarisation du mortier.L’objectif de cette thèse est de comprendre les phénomènes initiateurs de cette fissuration et d’évaluer son impact sur l’adhérence. Le couplage entre hydratation et séchage, le dosage en éther de cellulose et la rugosité du support sont les principaux paramètres étudiés. Les dispositifs expérimentaux développés au cours de ces travaux mises en place révèlent que ces trois paramètres influencent significativement la fissuration des mortiers. Aucun lien clair n’a cependant pu être mis en évidence entre fissuration et adhérence. / The quality of adherence between a coating mortar and its substrate, such as building front wall, depends on environmental conditions. Especially, the restraint of the drying shrinkage of the mortar by the substrate usually results in tensile stresses. This could lead to cracking or even debonding. The main objective of the present PhD dissertation is to study the cracking phenomenon due to restrained drying shrinkage and its impact on the failure of the mortar/substrate system. The interaction between cement hydration and drying, the content of cellulose ether (used as chemical admixture) and the substrate roughness are the main studied parameters. For this purpose, several original experimental devices were developed. In particular, cracking was investigated with digital image correlation. The three studied parameters appeared to influence significantly the adherence and cracking. However, no clear relation between cracking and adherence could be emphasized.

Les composés polymacrocycliques présentent un grand intérêt grâce à leurs caractéristiques remarquables de coordination. Pour la première fois, l’approche synthétique fonctionnelle aux diverses composés bi- et polycycliques contenant plusieurs fragments d’éthers aza-couronnes, aux cryptands et aux supercryptands à base d’éthers aza-couronnes a été élaborée par Krakowiak et ses collaborateurs au début des années 1990, par l’usage de simples réactions de substitution nucléophile. Actuellement, les composés hétéropolymorphes polymacrocycliques, capables de former des complexes polynucléaires avec différents métaux présentent le plus grand intérêt. Dans la grande majorité des travaux la synthèse de presque toutes les composés polymacrocycliques a été réalisée à l’aide des méthodes non orthodoxes, à l’exception des molécules, composées de plusieurs macrocycles porphyriques (de la diade et de la triade), pour l’obtention desquelles ont été appliquées les réaction de Suzuki, le couplage de Sonogashira et la réaction de Heck. Le laboratoire de synthèse organominérale de la Faculté de chimie de l’Université d’Etat de Moscou a accumulé une riche expérience dans l’utilisation de l’amination pallado-catalysée pour la synthèse de diverses composés macrocycliques et polymacrocycliques, et, actuellement, on étudie activement l’arylation cupro-catalysée des di- et polyamines. À cet égard, l’étude de l’amination cupro-catalysée pour la synthèse de composés polymacrocycliques qui contiennent comme connecteurs des diamines et des polyamines a permis développer des méthodes de catalyse métallique et d’obtenir de nouveaux types de conjugués polytopiques et polymacrocycliques, qui comprennent dans leur composition structurelle des fragments éthers aza-couronnes, porphyrines et calixarènes, étudiés pour leur capacité à détecter des cations des métalliques.Le but de ces recherches est de développer des méthodes catalytiques de synthèse de conjugués polymacrocycliques qui contiennent dans leur composition structurale des fragments éthers aza-couronnes, des porphyrines et des calix[4]arènes et d’étudier leurs capacités à détecter des cations métalliques. Pour atteindre cet objectif, il est nécessaire de résoudre les problèmes suivants: 1) établir la généralité de l’amination catalysée par le Cu(I) des dérivés éthers aza-couronnes et des porphyrines contenant des halogènes et de synthétiser les dérivés aminés; 2) développer des méthodes de la macrocyclisation catalytique pour obtenir des composés macrobicycliques et macrotricycliques qui contiennent dans leur structure des fragments éthers diaza-couronnes, des tétraazamacrocycles ( cyclènes et cyclames) et des calix[4]arènes; 3) modifier les composés macrocycliques et macrobicycliques par des substituants fluorophores, y compris des porphyrines; 4) à l’aide de la spectroscopie UV et de la fluorescence, étudier la liaison cations métalliques-polymacrocycles et identifier les détecteurs potentiels moléculaires fluorescents et colorimétriques. / Polymacrocyclic compounds are of great interest due to their unique coordination properties. The first convenient synthetic approach to various polycyclic compounds containing several azacrown-ether moieties, to cryptands and supercryptands, based on azacrown-ethers, has been developed by Krakowiak and coworkers in the beginning of 1990s using simple nucleophilic substitution reactions. At present time heteropolytopic polymacrocyclic compounds, capable of forming polynuclear complexes with various metals, attract the utmost interest. In the majority of publications dealing with the synthesis of polymacrocyclic compounds non-catalytic approaches were applied, except for several porphyrin dyads and triads, which were obtained using Suzuki, Sonogashira and Heck reactions. The laboratory of organoelement compounds of Chemistry Department of Lomonosov Moscow State University has a great experience of the application of Pd-catalyzed amination reactions for the synthesis of polymacrocyclic compounds, nowadays Cu-catalyzed arylation of di- and polyamines is under investigation. Bearing it in mind we have found the research for Cu-catalyzed amination to be important in synthesis of polymacrocyclic compounds containing di- and polyamine linkers; as well as the synthesis of new types of polytopic polymacrocyclic conjugates, bearing azacrown-ether, porphyrin and calixarene moieties, by means of Pd- and Cu-catalyzed reactions; and studying their properties as metal cations detectors.The aim of the research is to develop catalytic synthetic approaches to polymacrocyclic conjugates, bearing azacrown-ether, porphyrin and calix[4]arene moieties, and to study their abilities as detectors for metal cations. For this purpose it is necessary to carry out the following investigations: 1) to study the regularities of Cu(I)-catalyzed amination of halogen derivatives of azacrown-ethers and porphyrins and to synthesize corresponding amino derivatives; 2) to develop the methods for the catalytic macrocyclization aimed at the synthesis of macrobicyclic and macrotricyclic compounds, containing diazacrown-ether, cyclen, cyclam and calix[4]arene moieties; 3) to introduce fluorophoric fragments (including porphyrins) into macrocyclic and macrobicyclic compounds; 4) to investigate metal cations binding by thus synthesized polymacrocycles using UV and fluorescent spectroscopy, and to find possible fluorescent and colorimetric detectors among them.

Novel cage-functionalized azacrown ethers, i.e. 51, 52, 53, 55, 57, 61 and 62, which have various crown cavity and different number of nitrogen atoms incorporated, have been prepared. X-ray structures of 53, 55 and 57 have been obtained for the study of the crown topological structure. The complexation properties of crown 51, 52, 57, 61 and 62 have been evaluated via alkali metal picrate extraction, silver picrate extraction and ESI-MS study. The novel cage-fuctionalized azacrown ethers generally exhibit high avidity and selectivity towards Ag+ versus alkali metal ions and some transition metals i.e. Cu2+, Mn2+, Zn2+, Ni2+ and Pb2+. Crown 61 displays significant avidity and selectivity toward K+ in alkali metal picrate extraction experiments vis-à-vis the remaining alkali metal picrates. Three types of ditopic ion-exchange receptors for sodium hydroxide extraction study have been designed. All of the crown ether molecules have proper cavity for selective sodium complexation and have weakly acidic ionizable alcohols for sodium-proton exchange under strongly basic conditions. Crown 80 and 81 were synthesized; key intermediates for the synthesis of crown 82, 83 and 84 have been prepared. The preparation of 99 afforded an unexpected crown 103. The preparation of 109 had been attempted, but could not be successfully isolated. Four novel cage-functionalized calix[4]arene crown-5, i.e. 113-116, have been synthesized. The structures of 113 and 116 have been established by X-ray crystal structural analysis and NMR spectral analysis. The complexation properties of the four ionic receptors have been studied via alkali metal picrate extraction experiments. Crown 115 and 116 display more than modest avidity toward alkali metal ions and are most selective toward K+ vis-à-vis 113 and 114.

This work investigates processing-microstructure-property relationships of a model cryogenically mechanically alloyed polymer-polymer system: polycarbonate (PC) and poly (ether ether ketone) (PEEK). Mechanically milled and alloyed powders were characterized using a variety of techniques including microscopy and thermal analysis. Cryogenically mechanically alloyed powders processed for 10 hours were shown to have a sub-micron level two-phase microstructure. These powders were processed into testable coupons using a mini ram-injection molder; microstructure and bulk mechanical properties of the coupons were investigated as a function of mechanical alloying and injection molding parameters. Atomic force microscopy, transmission electron microscopy, and scanning transmission X-ray microscopy revealed that the intimate blending achieved during the mechanical alloying process is not retained upon post-processing using a conventional polymer processing technique. Injection molded coupons were tested in 3-point bend mode via dynamic mechanical and quasi-static mechanical testing. Results demonstrated that no improvement in energy to break, strain at failure, or failure strength was achieved in coupons made from cryogenically mechanically alloyed powders compared to those of coupons made from non-mechanically alloyed samples. / Ph. D.

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At the time this work was begun, there was some confusion about the technique necessary for the successful synthesis of organomagnesium compounds in hydrocarbon solvents and without solvents. It was decided to repeat the work of Bryce-Smith and Zakharkin. Thus began the study of the synthesis of organomagnesium compounds without solvents; the study of the reaction products of these organomagnesium compounds in hydrocarbons plus 2-butanone compared to the reaction products of the corresponding etheral Grignard reagent plus 2-butanone; and a preliminary study of the nature of these organomagnesium compounds in hydrocarbon solvents.

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