The synthesis of polyesters and copolyesters containing the bicycl o[2. 2.2]octane ring and 1,4-cycl ohexanedi acetic acid and 1,4-cyclohexanedimethanol spacers are discussed. The following homopolyesters were synthesized: poly[oxy(2-methyll, 4-phenylene)oxycarbonyl-l,4-bicyclo[2.2.2]octylenecarbonyl] I; and poly[oxy(2-chloro-l,4-phenylene)oxycarbonyl-l,4-bicyclo[2.2.2]octy-1 enecarbonyl] II. The following copolyesters were synthesized: poly[oxy (2-chl oro- 1,4-phenyl ene )oxycarbonyl-l ,4-bi cycl o[2. 2. 2]octyl enecarbonyl-co-oxy- (2-chloro-1,4-phenylene)oxysebacoyl] III; poly[oxy(2-methyl-l,4- phenylene)oxycarbonyl-l,4-bicyclo[2.2.2]octylene-co-oxy(2-methyl-l,4- phenyl ene)oxysebacoyl] IV; poly[oxy(2-methyl-l,4-phenylene)oxyterephthaloyl- co-oxy(2-methyl-l,4-phenylene)oxy-l,4-cyclohexanediacetoyl] V; poly[oxy(2-methyl-1,4-phenylene)oxyterephthaloyl-co-oxymethylene-1,4 cyclohexylenemethyleneoxyterephthaloyl] VI; and poly[oxy(2-chloro-1,4 phenylene)oxyterephthaloyl-co-oxymethylene-1,4 cyclohexylenemethyleneoxyterephthaloyl]VII. The resulting homopolyesters and copolyesters were characterized by proton NMR, DSC, TGA, IR, solution viscosity, and polarizing optical microscopy.

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Depuis plusieurs décennies, les polyesters aliphatiques (polycaprolactone (PCL), polylactide (PLA), polyglycolide (PGA)) et leurs copolymères ont été retenus pour des applications médicales grâce à leur biodégradabilité et leur biocompatibilité. Parmi leurs applications médicales, on s’intéresse ici à la délivrance des médicaments par des copolymères amphiphiles et à l’ingénierie tissulaire. Les polyesters aliphatiques souffrent cependant d’une hydrophobie importante et de l’absence de groupes fonctionnels. Pour pallier ces problèmes, plusieurs stratégies demodifications chimiques ont été proposées dans la littérature parmi lesquelles on cite : l’hydrolyse, la modification par plasma, la post-polymérisation alcyne azoture et la modification photochimique thiol-yne. Ces modifications servent à introduire des polymères hydrophiles (ex. le polyéthylène glycol) ou des groupes fonctionnels qui peuvent améliorer la biocompatibilité de polyesters. Dans ce manuscrit, on s’intéresse à la modification de la PCL et du PLA par voie photochimique thiol-yne qui présente l’avantage d’être rapide, versatile, applicable en solution comme en surface et de ne pas nécessiter l’utilisation d’un catalyseur métallique qui peut être nocif pour les applications médicales. Dans une première partie, la modification de la PCL a été faite en solution et des copolymères amphiphiles PCL-g-PEG ont été synthétisés. La stratégie de greffage « grafting to » en deux étapes a été choisie en partant de polymères commerciaux. Une optimisation des conditions de modification par voie anionique de PCL, suivi d’une photoaddition thiol-yne, nous a permis d’obtenir des copolymères avec des balances hydrophiles/hydrophobes contrôlées. L’impact de l’hydrophilie des copolymères sur la formation de nanoobjets, leurs concentrations d’aggrégation critique et leurs tailles a été étudié. L’encapsulation de curcumine comme agent anticancéreux et la cytotoxicité des nanovecteurs envers des cellules cancéreuses ont été vérifiées. Dans un second temps, ces copolymères ont été décorés par un peptide de ciblage et un peptide clivable enzymatiquement en vue de leur utilisation dans des traitements anticancéreux. L’effet biologique de ces copolymères encapsulant des principes actifs est vérifié in vitro sur des cellules cibles exprimant plus ou moins d’intégrines ou de métalloprotéases. Dans une seconde partie, des fibres PLA ont été modifiées en surface par des nanoparticules inorganiques afin de générer des hybrides covalents d’intérêts pour des applications en ingénierie tissulaire. De manière analogue aux modifications en solution, ces hybrides ont été obtenus en deux étapes par modification par voie anionique de nanofibres de PLA, suivi par un greffage covalent de nanoparticules d’oxyde de fer en suivant une stratégie photochimique thiol-yne. / For decades, aliphatic polyesters (polycaprolactone (PCL), polylactide (PLA), polyglycolide (PGA)) and their copolymers have been selected for medical applications because of their biodegradability and their biocompatibility. Among their medical applications, we are interested in drug delivery system based on amphiphilic copolymers and tissue engineering. However, aliphatic polyesters suffer from significant hydrophobicity and the absence of functional groups. To overcome these drawbacks, several strategies ofchemical modifications have been reported in literature among which we present: hydrolysis, plasma modification, post polymerization modification by copper catalyzed azide alkyne cycloaddition and thiol-yne post polymerization modification. These modifications have been used to introduce hydrophilic polymers (eg. polyethylene glycol) or functional groups on the polyester chains that can enhance the biodegradability of polyesters. In this manuscript, we are interested in modifying PCL and PLA chains by thiol-yne photochemical route. This method is rapid, versatile, applicable in solution as well as on surface and it does not require the use of a metallic catalyst which can be harmful for medical applications. First, PCL modification was done in solution and amphiphilic copolymers PCL-g-PEG were synthesized. The strategy “grafting to” in two steps has been selected starting from commercial polymers. Conditions optimization of anionic activation, followed by thiol-yne photoaddition, allowed us to obtain copolymers with controlled ratios hydrophilic/hydrophobic. The impact of copolymers hydrophilicity on nanoobjets formulation, critical micelle concentration and sizes was studied. Curcumin encapsulation as an anticancer agent and nanocarriers cytotoxicity towards cancer cells were verified. In addition, these copolymers were then decorated with a targeting peptide and an enzymatically cleavable peptide in the aim of using them in cancer treatment. The biological effect of anticancer loaded copolymer was verified in vitro on target cells expressing more or less integrins or metalloproteases. Second, PLA fibers were modified with inorganic nanoparticles and generate covalent hybrids for purposes in tissue engineering of neuronal cells. Analogously to the solution modification, these hybrids were obtained in two steps by anionic activation of PLA fibers, followed by covalent grafting of iron oxide nanoparticles according to a thiol-yne photochemical strategy.

Poly(butylene succinate) (PBSu) and two poly(butylene succinate-co-propylene succinate)s (PBPSu 95/5 and PBPSu 90/10) were synthesized via the direct polycondensation reaction. The copolyesters were characterized as having 7.0 and 11.5 mol% propylene succinate (PS) units, respectively, by 1H NMR. Copolyesters were characterized as random, based on 13C NMR spectra. They were fully investigated during nonisothermal crystallization and thermal degradation through various approaches in this study. A differential scanning calorimeter (DSC) and a polarized light microscope (PLM) adopted to study the nonisothermal crystallization of these polyesters at a cooling rate of 1, 2, 3, 5, 6 and 10 ºC/min. Morphologies and the isothermal growth rates of spherulites under PLM experiments were monitored and obtained by curve-fitting, respectively. These continuous rate data were analyzed with the Lauritzen-Hoffman equation. A transition of regime II ¡÷ III was found at 95.6, 84.4, and 77.3 ºC for PBSu, PBPSu 95/5, and PBPSu 90/10, respectively. DSC exothermic curves show that all of the nonisothermal crystallization occurred in regime III. DSC data were analyzed using modified Avrami, Ozawa, Mo, Friedman and Vyazovkin equations. Ozawa equation does not accurately describe the nonisothermal crystallization kinetics of this polyester because part of the crystallization is secondary crystallization. All the results of PLM and DSC measurements indicate that incorporation of minor PS units into PBSu markedly inhibits the crystallization of the resulting polymer. The melting behavior of nonisothermally crystallized samples presents a continuous melting¡Vrecrystallization¡Vremelting process. Additionally, three absorption bands during the nonisothermal crystallization were identified for PBSu and two PBPSu copolyesters, namely, 916, 955, 1045 cm-1 in the attenuated total reflectance FTIR spectra. Thermogravimetric analysis (TGA)-FTIR was heated at 5 ºC/min under N2 to monitor the degradation products of these three polyesters. FTIR spectra revealed that the major products were anhydrides, which were obtained following two cyclic intramolecular degradation mechanisms by breaking the weak O-CH2 bonds around a succinate group. Thermal stability at heating rates of 1, 3, 5, and 10 ºC/min under N2 was investigated using TGA. The model-free methods of Friedman and Ozawa equations are useful for studying the activation energy of degradation in each period of mass loss. The results reveal that the random incorporation of minor PS units into PBSu did not markedly affect their thermal resistance. Two model-fitting mechanisms were used to determine the loss mass function f(£\), the activation energy and the associated mechanism. The mechanism of autocatalysis nth-order, with f(£\)=£\m(1-£\)n, fitted the experimental data much more closely than did the nth-order mechanism given by f(£\)=(1-£\)n. The obtained activation energy was used to estimate the failure temperature (Tf). The values of Tf for a mass loss of 5% and an endurance time of 60,000 hr are 160.7, 155.5, and 159.3 ºC for PBSu and two the copolyesters, respectively.

Poly(butylene succinate) (PBSu), poly(2-methyl-1,3-propylene succinate) (PMPSu), and their two novel poly(butylene succinate-co-2-methyl-1,3-propylene succinate)s (PBMPSu 95/05 and PBMPSu 90/10) were synthesized by a two-stage esterification reaction. PBMPSu 95/05 and PBMPSu 90/10 were characterized as having 6.5 and 10.8 mol% 2-methyl-1,3-propylene succinate (MPS) units, respectively, by 1H NMR. These copolymers were characterized to be random from the 13C NMR spectra. In this study, the nonisothermal crystallization and thermal degradation behaviors of the polyesters were investigated via different approaches. A differential scanning calorimeter (DSC) and a polarized light microscope (PLM) were employed to investigate the nonisothermal crystallization of these copolyesters and neat PBSu. Morphology and the isothermal growth rates of spherulites under PLM experiments at three cooling rates of 1, 2.5 and 5 ¢XC/min were monitored and obtained by curve-fitting. These continuous rate data were analyzed with the Lauritzen-Hoffman equation. A transition of regime II ¡÷ III was found at 96.2, 83.5, and 77.9 ¢XC for PBSu, PBMPSu 95/05, and PBMPSu 90/10, respectively. DSC exothermic curves at five cooling rates of 1, 2.5, 5, 10 and 20 ¢XC/min show that almost all of the nonisothermal crystallization occurred in regime III. DSC data were analyzed using modified Avrami, Tobin, Ozawa, Mo, Friedman and Vyazovkin equations. All the results of PLM and DSC measurements reveal that incorporation of minor MPS units into PBSu markedly inhibits the crystallization of the resulting polymer. The nonisothermal crystallization behavior of these polyesters was also investigated using a Fourier-transform infrared spectrometer (FTIR) with an attenuated total reflection (ATR). The absorbance peaks of crystals for the £\ form (918, 955, and 1045 cm-1) of PBSu and PBMPSu copolyesters were observed by ATR-FTIR under nonisothermal crystallization. When these semicrystalline polyesters started to be solidified from the melt state, these characteristic absorption bands for PBSu and its copolyesters crystals have been detected. In this study, the thermal degradation mechanisms of PBSu, PMPSu, PBMPSu 95/05, and PBMPSu 90/10 were investigated using a thermogravimetric analyzer combined Fourier-transform infrared spectrometer (TGA-FTIR) and a pyrolysis-gas chromatography¡Vmass spectrometry (Py-GC-MS). The volatile products evolved from the thermal degradation of these two copolyesters were identified to be anhydride, ether, ester, alcohol, alkene, aldehyde, and CO2. FTIR spectra displayed that the main degradation products for these four polymers were anhydrides. Moreover, PBSu-rich PBMPSu copolymers exhibited the same thermal degradation mechanism as that of PBSu at lower thermal degradation temperatures (< 403 ºC) and as that of PMPSu at higher thermal degradation temperatures (> 403 ºC) by the TGA-FTIR analysis. The results of the TGA-FTIR analysis clearly demonstrates that the influence of MPS units on the thermal degradation process is gradually increased as the temperature increases for PBMPSu copolymers. The degradation mechanism of PBMPSu at lower thermal degradation temperatures and PBSu mainly follows the £]-hydrogen bond scission mechanism and the back-biting process from the polymer chains. Moreover, the degradation mechanism of PBMPSu at higher thermal degradation temperatures and PMPSu occurred mainly through the £]-hydrogen bond scission and secondarily through £\-hydrogen bond scission. Finally, the thermal stability and degradation kinetics of these polyesters were investigated using a TGA at heating rates of 1, 3, 5, and 10 ºC/min under dynamic nitrogen. The activation energies of thermal degradation in elective conversions were estimated using the Friedman and Ozawa methods. The results clearly demonstrated that the thermal stabilities of these PBMPSu copolyesters were slightly reduced with the incorporation of minor MPS units into PBSu. Two model-fitting methods of nth-order and autocatalysis nth-order reaction mechanisms were adopted to determine the mass loss function f(£\), the activation energy and the associated degradation parameters. The results revealed that the mechanism of autocatalysis nth-order fitted the experimental data much more closely than did the nth-order mechanism for PBSu, PMPSu and PBMPSu copolymers.

La protection de l’environnement est au cœur de toutes les pressions sociétales. La peinture anti-fouling est un moyen efficace et peu onéreux de protection des carènes immergées. Il est nécessaire de développer de nouveaux revêtements alternatifs aux peintures organnostanniques, plus respectueux de l’environnement. L’objectif de cette thèse est de synthétiser des copolyesters biodégradables à base de -caprolactone et de -valérolactone de masse molaire et de composition contrôlées (polymérisation par ouverture de cycle). Le couple catalytique utilisé est le 2-éthylhexanoate d’étain avec l’octanol. La cristallinité des copolymères a été mesurée. Puis la mouillabilité, l’hydratation et la dégradation de films de polymère en conditions de laboratoire ont permis de déterminer la structure du liant biodégradable respectant les exigences d’un cahier des charges. Ces copolymères sont incorporés dans des formulations érodables de peintures antisalissures marines. Les peintures sont immergées afin de tester leurs propriétés anti-fouling. L’observation du microfouling est réalisée par microscopie confocale à balayage laser tandis que l’adhésion des macro-organismes est évaluée in situ. L’efficacité anti-salissure marine des revêtements a été validée pendant huit mois d’immersion au port de Kernevel (Lorient). Les perspectives de travail concernent la diminution de la quantité de biocides dans les revêtements, tout en maintenant une activité conforme aux restrictions industrielles. / Antifouling paints are currently the most used hulls protection system. New antifouling coatings need to be developed with less environmental impact than organostannic paints. Copolyester of -caprolactone and -valerolactone with controlled molar mass and composition are synthesized by ring opening polymerization with stannous octanoate and octanol. Crystallinity of copolyester are measured. The evolution of water uptake, hydrophobicity properties and hydrolytic degradation of the binders surfaces have been investigated during the immersion in controlled medium. Copolymers are incorporated in an antifouling paint formulation and then immersed in natural conditions. Efficiency was validated during eight months of time immersion in the Kernevel harbour.

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No description available.