Cette étude s’intéresse aux procédés d’ignifugation d’un élastomère, le copolymère d’éthylène acétate de vinyle (EVM) vulcanisé, et plus particulièrement à l’ajout en masse de retardateurs de flamme commerciaux. L’objectif de ce travail consiste à mettre au point une formulation à base EVM destinée aux domaines de la câblerie et des transports, ignifugée et à haute tenue mécanique, ainsi qu’à comprendre les phénomènes d’ignifugation mis en jeu. L’évaluation de différents types d’additifs, sur le plan mécanique et retard au feu, a permis de dégager une combinaison innovante associant le trihydroxyde d’aluminium (ATH) et le diéthylphosphinate d’aluminium (OP1230). Le mode d’action de l’ATH dans l’EVM, généralement attribué à sa déshydratation endothermique, a été revisité à l’aide d’une approche cinétique de la dégradation du système EVM/ATH. Ces résultats ont été corrélés à l’étude de l’évolution du matériau soumis à des conditions incendie. Il a été montré que l’endothermicité de la réaction n’a qu’un rôle secondaire, l’additif agissant principalement en formant au sein du matériau une structure protectrice d’alumine jouant le rôle de barrière thermique et ralentissant ainsi le transfert de masse lors de la combustion. Pour la formulation complète (EVM/ATH/OP1230), les interactions chimiques entre additifs et polymère et les mécanismes d’action de l’OP1230 et de la combinaison ATH/OP1230 ont été étudiés. L’effet de synergie observé entre les deux additifs est attribué à la formation d’une couche protectrice vitreuse résistante à la surface du matériau pendant la combustion, couplée à la libération d’espèces phosphorées agissant en phase gaz comme inhibiteurs de flamme. / This study is dedicated to the formulation of an innovative flame retardant material based on elastomeric vulcanized ethylene-vinyl acetate copolymer (EVM) used in the fields of cable and transportation, and to the comprehension of the flame retardant phenomena. The screening of various additives, evaluated in EVM in terms of mechanical and fire retardant properties, allowed the determination of an innovative combination, made of aluminium trihydroxide (ATH) and aluminium diethyl phosphinate (OP1230). The ATH mode of action, generally assumed to be a cooling effect, was revisited by a kinetic approach of the thermal degradation of the EVM/ATH formulation in oxidative and pyrolytic conditions, associated with the investigation of the evolution of the material in simulated fire conditions. It was found that the cooling effect occurs, but the main protective effect of ATH consists in the formation during combustion of an alumina layer, diminishing the mass and heat transfer and thus the flame feeding. In the complete formulation (EVM/ATH/OP1230), the chemical interactions between ATH, OP1230 and the polymer were investigated, revealing that the synergistic effect provided by the two additives results from the creation during combustion of a resistant glassy layer. Moreover phosphorous species are evolved in the gas phase during combustion, acting as flame inhibitors.

No description available.

Cette étude s’intéresse aux procédés d’ignifugation de deux thermoplastiques techniques, le poly téréphtalate de butylène (PBT) et le polyamide 6 (PA6), à application dans le domaine électrique et électrotechnique. Plus précisément, l’accent est mis sur l’ajout en masse de retardateurs de flammes à base d’azote et de phosphore. L’objectif de ce projet consiste à préparer de nouveaux retardateurs de flamme par voie de synthèse organique. Dans un premier temps, cinq phosphinates d’aluminium ont été préparés par amidification de l’acide hydroxyphenylphosphoryl propanoïque et réaction avec un promoteur d’aluminium. Ces sels ont été incorporés au PBT et au PA6, seuls ou en combinaison avec des co-additifs, puis testés à l’UL-94, test témoin de la propagation verticale de la flamme, très utilisé dans l’industrie électrique et électrotechnique. Parmi les cinq sels, seul le phenylamide de l’acide hydroxyphenylphosphoryl propanoïque (PAS) s’est avéré être un retardateur de flammes efficace. D’autres tests ont été réalisés pour approfondir les résultats. Une instrumentation du test UL-94 a également été développée pour établir les bases de la compréhension du mécanisme d’action de la formulation, approfondies ensuite dans une série de microanalyses. Il a été démontré que le PAS se décompose en entraînant la scission des chaînes de PBT et le refroidissement du matériau. La libération de composés phosphorés en phase gaz, bien que moins efficace que pour d’autres composés commerciaux, suffit à donner à la formulation sa propriété d’auto-extinction. / This study deals with the flame retardancy of two engineering plastics, the poly(butylene terephthalate) (PBT) and the polyamide 6 (PA6), widely used in the electrical and electronic equipment (EEE). The focus is made on the incorporation of phosphorus- and nitrogen-containing flame retardant (FR) additives. The main goal of this project was to prepare novel FR through organic synthesis. Five aluminum phosphinates were prepared by reaction of amines on hydroxyphenylphosphnyl propanoic acid and an aluminum promoter. The salts were incorporated to PBT and PA6, with or without co-additives, and the materials were tested in the UL-94, test investigating the vertical propagation of the flame and widely used in the EEE industry. Among the five salts, only the aluminum salt of phenyl amide of hydroxyphenylphosphnyl propanoic acid showed outstanding properties as FR. Other tests were carried out, among which an instrumentation of the UL-94 test, to build a way to the comprehension of mechanisms. First observations were completed by various microanalyses. It has been shown that the decomposition of PAS enhances that of PBT in parallel to its cooling. The liberation of phosphorus-containing species in the gas-phase, despite les efficient than in the case of other commercial FR, gives the formulation its auto-extinguishing character.

Les textiles jouent un rôle important dans notre vie quotidienne. La plupart des fibres textiles et des tissus sont fabriqués à partir de polymères à base de pétrole, des matériaux inflammables et potentiellement dangereux. Afin de conférer le caractère ignifuge aux fibres textiles; entre autres, les composés halogénés sont plus efficaces et largement utilisés pour améliorer le comportement ignifuge des matières textiles. Cependant, en raison de la toxicité des composés halogénés et de l'épuisement progressif des ressources pétrolières, les communautés scientifiques et industrielles sont obligées de trouver des solutions alternatives. Par conséquent, on s’intéresse de plus en plus aux ressources durables, en particulier au développement de systèmes ignifugeants fabriqués à partir de ressources biologiques et respectueux de l’environnement non halogénés. Dans le contexte de l’utilisation de ressources biologiques, une attention particulière a été appelée pour la biomasse. Après la cellulose, la lignine est le deuxième polymère de biomasse le plus abondant et le principal à base d'unités aromatiques. En particulier, la lignine est avantageuse car c’est un coproduit des industries de la pâte à papier et de la fabrication du papier et non une ressource qui nécessite une production spécifique. En fait, sa structure chimique hautement aromatique permet d’améliorer différentes propriétés fonctionnelles telles que la résistance aux UV, l’antioxydant et l’ignifugation des polymères. Récemment, la lignine a fait l’objet d’une grande attention en tant qu’additif retardateur de flamme d'origine biologique en raison de son aptitude élevée à la formation de carbone après la décomposition thermique. Cette capacité de formation de carbone de la lignine en fait un candidat de choix comme source de carbone pour un système intumescent avec un autre additif ignifuge. Lors du chauffage, les matériaux intumescents ignifuges (FR) forment une couche carbonisée cellulaire expansée; agissant comme une barrière physique contre le transfert de chaleur et de masse, qui protège le matériau sous-jacent de l'action du flux de chaleur et de la flamme.Au meilleur de nos connaissances, aucune étude n'a été publiée concernant l'introduction de la lignine en tant que source de carbone dans les structures textiles pour leur conférer des propriétés ignifugeantes. Par conséquent, dans cette étude, la lignine a été introduite dans la structure textile lors de la composition. Cette thèse porte sur le développement de la structure textile ignifuge entièrement biosourcée. Pour atteindre cet objectif, l'approche en plusieurs étapes est adoptée. Dans une première étape, la matrice polymère biosourcée a été sélectionnée pour produire la structure textile et la méthode d’incorporation de la lignine a été étudiée et optimisée. Ensuite, les propriétés ignifuges apportées par la lignine ont été caractérisées et améliorées en ajoutant un additif ignifuge dans les formulations (par exemple, utilisation de sources acides pour développer un système intumescent pouvant améliorer la résistance des textiles au feu). Dans la deuxième phase du projet, la lignine a été combinée à la source d'acide d'origine biologique pour développer une nouvelle génération de structures durables (100% biosourcées) destinées aux marchés du textile. La principale avancée technologique consiste à utiliser et à combiner différents composants biosourcés utilisés dans d'autres industries, telles que l'industrie du plastique, afin de développer des solutions textiles. / It has been chosen to study valorization of low-cost industrial lignin as additive in designing the flame retardant (FR) system for polyamide 11 (PA) to develop biobased textile structure. The main focus of this thesis work is to consider lignin as carbon source and introduce in a textile structure in combination with phosphinate salt (FR agent). In the primary study, chemically different industrial lignins were incorporated in PA by extrusion to investigate the charring and fire retardant behaviour of the prepared binary blends. In addition, the introduction of sulphonated lignins significantly reduced the peak of the heat release rate (PHRR) and of the total heat release (THR), and a noticeable increase of the char residue was observed after forced combustion test. In the next approach, lignin was exploited as carbon source in combination with commercially available phosphinate FR (i.e., ZnP and AlP). To achieve this objective, a preliminary study carried out with laboratory grade lignin (LS) combined with ZnP to investigate the thermal stability and fire performance as well as the possible synergy between lignin and ZnP and with the polymer matrix. The results obtained in this study permitted to continue further, the practical implementation of lignin and multifilament production. In the next step, flame retarded blends were developed with direct addition of low-cost industrial lignins (LL and DL) with phosphinate FR. For the systematic understanding, various FR formulations were developed by varying the lignin and FR loading and characterized. Thermal decomposition analysis showed that the presence of lignin decreases the initial decomposition temperature (T5%) due to the decomposition of lignin which starts at a lower temperature region with the evolution of less thermally stable compounds and the maximum decomposition temperature (Tmax) shifts to higher temperature region, at this stage the formation of phenolic, carbonyls, hydrocarbons and CO2 along with phosphinate compounds occurs. Meanwhile, in the condensed phase thermally stable aromatic charred layer is formed because of lignin decomposition and phosphate compounds formation due to the presence of phosphinate metal salt. A higher amount of char residue is obtained when LL combined with ZnP/AlP as compared to the DL and ZnP/AlP blends. It is assumed that, during decomposition of LL, the sulfonate compounds release SO2 and transformed into thermally stable Na2SO4, hence giving rise to the stable char residue. The fire properties were assessed by cone calorimeter tests revealed the combination of lignin and phosphinate FR significantly reduced the PHRR and other fire-related parameters due to the formation of a protective char layer. The presence of lignin not only improve fire retardancy but also reduced the evolution of carbon monoxide (CO). More enhanced fire retardant properties were obtained with LL and ZnP/AlP combination reaches to 10 wt% in ternary blends, which not only promotes char formation but also confer the stability to char in the condensed phase. Furthermore, the most enhanced forced combustion results were obtained with LL and AlP (in particular, PA80-LL10-AlP10). Multifilament yarns were successfully produced for PA-DL-ZnP and PA-LL-ZnP combinations. However, the blends of AlP with lignin were not spinnable because of low compatibility and dispersion level of AlP in the polymer. Optical microscopy and tensile tests were performed to study the physical properties of multifilaments. A double layer (interlock structure) knitted fabrics were developed to evaluate fire behaviour analysis on fabric samples.

De par leur grande diversité chimique et leur implication dans de nombreux mécanismes biologiques, les molécules phosphorées font l'objet de nombreuses recherches scientifiques. Depuis près de 30 ans, plusieurs composés phosphorés ont été développés et utilisés pour leurs propriétés médicinales ou phytosanitaires. Les dérivés de type phosphinates ou phosphonates se sont révélés être des composés de choix, grâce à leur grande stabilité chimique et enzymatique. Par ailleurs, les sucres et leurs analogues ont largement démontré leur potentiel biologique en raison de leur implication dans de nombreux processus biologiques. Dans ce contexte, il a été envisagé de développer des analogues de sucres phosphorés possédant un atome de phosphore endocyclique. Il s'agit de structures totalement inédites obtenues à partir de précurseurs phosphorés simples et par des réactions de type : P-alkylation, Pudovik, ouverture d'époxyde, cyclisation par transacétalisation ou transestérification. Grâce à des synthèses en 4 à 7 étapes, deux familles de phosphinosucres ont été préparées ainsi qu'une famille de phosphonosucres en tant qu'analogues de sucre. En parallèle, la synthèse d'analogues de nucléosides phosphorés a également été étudiée par introduction de nucléobases sur les analogues de sucres phosphorés précédemment cités. Ces travaux ont mis en jeu des réactions issues à la fois de la chimie de nucléosides mais également de la chimie du phosphore, permettant d'accéder à des analogues de nucléosides totalement inédits dont l'activité antivirale a pu être évaluée. Enfin, une nouvelle famille de phosphonates nucléosidiques acycliques a été synthétisée en 6 ou 7 étapes en série pyrimidique. Deux prodrogues dérivées de la cytosine et de l'uracile ont également été préparées avec des groupements enzymolabiles de type Bis-(S-acyl-2-thioéthyle). L'ensemble des analogues de nucléotides synthétisés ont été évalués pour leurs propriétés antivirales contre les virus de l'hépatite C et du SIDA. Ainsi, à travers ce projet, trois grandes familles de nouvelles molécules phosphorées ont été développées : les hétérocycles phosphorés oxygénés en tant qu'analogues de sucres, des analogues de nucléosides phosphorés, une nouvelle classe de phosphonates nucléosidiques acycliques. / According to their wide chemical diversity and their implication in many biological processes, phosphorus compounds are intensively studied by organic chemists. Since 30 years, many phosphorus molecules have been developed and used for their biological properties in medicine or agrochemistry. Chemically and enzymatically stable compounds, phosphonates and phosphoninates are potential derivatives for drug design. Besides, sugars are an important biological family involved in numerous biological pathways which have widely revealed a high therapeutic potential. In this context, the first objective of these works was to develop sugar analogues with an endocyclic phosphorus atom (phosphasugars) to synthesize unpublished families of phosphinosugars and phosphonosugars. Their synthesis were carried out in 4 to 7 steps, using as key reactions : P-alkylation, Pudovik, epoxyde ring-opening reaction, cyclisation by transacetalisation or transesterification. Moreover, these phosphasugars were extended to the synthesis of new nucleoside analogues by introducing nucleobase on phosphasugar moiety. The antiviral activity of these new compounds was evaluated. Finally, a new class of acyclic nucleoside phosphonates was prepared in pyrimidinyl series. Different nucleotide analogues and prodrugs were synthesized in 6-7 steps with uracil, thymine and cytosine and evaluated against HCV and HIV.

Two linear aminodiphosphinates (H3L1 , H5L2 ) and one cyclic aminodiphosphinate (H2L3 ) were prepared and studied. Newly prepared compounds were characterized by NMR, MS and EA (elemental analysis). Acid-base and coordination properties of ligands were studied. Protonation constants and stability constants of complexes with Zn2+ , Ni2+ and Cu2+ metal ions were determined by potentiometry. Keywords Ligands, dissociation constants, potentiometry, phosphinates, complexes.

The Diploma Thesis deals with preparation of one phoshonate and two phospinate derivatives of dipicolylamine. Dissociation constants of prepared ligands were determined by potentiometric and NMR titration. Coordination properties of the compounds were studied by combination of potentiometry and UV-VIS spectrophotometry. Stability constants of complexes with selected transition metal ions (Cu2+ , Ni2+ a Zn2+ ) and alkali-earth metals ions (Ca2+ , Mg2+ ) were calculated. Acid-base and coordination properties in the solid state were studied by X-ray diffraction on single-crystals.

Perfluoroalkyl carboxylates (PFCAs) and perfluoroalkane sulfonates (PFSAs)are anthropogenic fluorinated surfactants that have been detected in almost every environmental compartment studied, yet their production and applications are far outweighed by those of other higher molecular weight fluorinated surfactants used in commerce. These fluorinated surfactants are widely incorporated in commercial products, yet their post-application fate has not been extensively studied. This thesis examines various biological and environmental processes involved in the fate of these surfactants upon consumer disposal. Specific focus was directed towards the environmental chemistry of polyfluoroalkyl phosphate esters (PAPs), perfluoroalkyl phosphonates (PFPAs), and perfluoroalkyl phosphinates (PFPiAs), and their potential roles as sources of perfluoroalkyl acids (PFAAs) in the environment. PAPs are established biological precursors of PFCAs, while PFPAs and PFPiAs are newly discovered PFAAs in the environment. Incubation with wastewater treatment plant (WWTP) microbes demonstrated the ability of PAPs to yield both fluorotelomer alcohols (FTOHs), which are established precursors of PFCAs, and the corresponding PFCAs themselves. WWTP biosolids-applied soil-plant microcosms revealed that PAPs can significantly accumulate in plants along with their degradation metabolites. This has implications for potential wildlife and human exposure through the consumption of plants grown and/or livestock raised on farmlands that have been amended with contaminated biosolids. A number of compound-and environmental-specific factors were observed to significantly influence the partitioning of PFPAs and PFPiAs between aqueous media and soil, as well as, aquatic biota during sorption and bioaccumulation experiments respectively. In both processes, PFPAs were primarily observed in the aqueous phase, while PFPiAs predominated in soil and biological tissues, consistent with the few environmental observations of these chemicals made to date. Detection of the PAP diesters (diPAPs), PFPiAs, and fluorotelomer sulfonates (FTSAs),all of which are used commercially, in human sera is evidence of human exposure to commercial fluorinated products, but the pathways by which this exposure occurs remain widely debated. Overall, this work presents novel findings on the environmental fate of commercial fluorinated surfactants and each of the process studied shows a clear link between the use of commercial products and the fluorochemical burden currently observed in the environment.

Perfluoroalkyl carboxylates (PFCAs) and perfluoroalkane sulfonates (PFSAs)are anthropogenic fluorinated surfactants that have been detected in almost every environmental compartment studied, yet their production and applications are far outweighed by those of other higher molecular weight fluorinated surfactants used in commerce. These fluorinated surfactants are widely incorporated in commercial products, yet their post-application fate has not been extensively studied. This thesis examines various biological and environmental processes involved in the fate of these surfactants upon consumer disposal. Specific focus was directed towards the environmental chemistry of polyfluoroalkyl phosphate esters (PAPs), perfluoroalkyl phosphonates (PFPAs), and perfluoroalkyl phosphinates (PFPiAs), and their potential roles as sources of perfluoroalkyl acids (PFAAs) in the environment. PAPs are established biological precursors of PFCAs, while PFPAs and PFPiAs are newly discovered PFAAs in the environment. Incubation with wastewater treatment plant (WWTP) microbes demonstrated the ability of PAPs to yield both fluorotelomer alcohols (FTOHs), which are established precursors of PFCAs, and the corresponding PFCAs themselves. WWTP biosolids-applied soil-plant microcosms revealed that PAPs can significantly accumulate in plants along with their degradation metabolites. This has implications for potential wildlife and human exposure through the consumption of plants grown and/or livestock raised on farmlands that have been amended with contaminated biosolids. A number of compound-and environmental-specific factors were observed to significantly influence the partitioning of PFPAs and PFPiAs between aqueous media and soil, as well as, aquatic biota during sorption and bioaccumulation experiments respectively. In both processes, PFPAs were primarily observed in the aqueous phase, while PFPiAs predominated in soil and biological tissues, consistent with the few environmental observations of these chemicals made to date. Detection of the PAP diesters (diPAPs), PFPiAs, and fluorotelomer sulfonates (FTSAs),all of which are used commercially, in human sera is evidence of human exposure to commercial fluorinated products, but the pathways by which this exposure occurs remain widely debated. Overall, this work presents novel findings on the environmental fate of commercial fluorinated surfactants and each of the process studied shows a clear link between the use of commercial products and the fluorochemical burden currently observed in the environment.

Asymmetric hydrogenation has emerged as a versatile methodology to obtain a wide range of chiral precursors. This thesis focused on the synthesis of new chiral ligands and the expansion of the substrate scope of asymmetric hydrogenations. Paper I described the synthesis and evaluation of N,P-ligands for the Ir-catalyzed hydrogenations of unfunctionalized olefins. The substrate scope of Ir-catalyzed asymmetric hydrogenations is limited to a narrow range of “test” olefins. The foremost focus of this thesis was to expand the substrate scope of Ir-catalyzed asymmetric hydrogenations. Papers II and III disclosed the potential of the N,P-ligated Ir complexes in hydrogenation of the enol phosphinates. This substrate class is attractive because the hydrogenated products are chiral alkylphosphinates that can be transformed into chiral alcohols and chiral phosphines without sacrificing enantiopurity. A wide range of enol phosphinates were hydrogenated to excellent conversions and enatioselectivities. The hydrogenation of purely alkyl-substituted enol phosphinates in very high conversions and ee values was emphasized in these studies. Paper IV described the investigation of unfunctionalized enamines as substrates in Ir-catalyzed hydrogenation studies. The hydrogenation results and structural limitations of the substrates are presented. Paper V described the asymmetric hydrogenation of diphenylvinylphosphine oxides, di- and trisubstituted vinyl phosphonates. The hydrogenation of diphenylvinylphosphine oxides gives direct access to protected chiral phosphines. The hydrogenated products of vinylphosphonates are highly synthetically useful in pharmaceutical and material chemistry. Hydrogenation of E/Z mixtures of carboxyethyl vinylphosphonates with perfect enantioselectivities was striking in these studies. In paper VI, we have reported the development of a new, highly enantioselective synthetic route to building blocks with CF3 at the chiral center. Several functionalized and unfunctionalized CF3-substituted olefins were hydrogenated with varied degree of success. This methedilogy is useful in the formation of chiral fluorine-containing molecules for a wide range of applications. Paper VII described the hydrogenation of imines using the phosphine-free Cp*Ru/diamine complexes. Chiral version of this reaction was also examined. Despite the modest results, this is the first study to use phosphine-free Cp*Ru/diamine complexes as catalysts for the reduction of C=N double bonds.