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In this study we report a series of partially biobased new (hetero)aromatic copolyesters, namely poly(ethylene-bis(ethyl 2-furoate)-co-ethylene 5-nitroisophthalate)s synthesised via the two-step melt polycondensation process, by combining commercially available dimethyl 5-nitroisophthalate and a biobased bisfuranic diester derivative (DEF), and ethylene glycol. Their expected molecular structure was confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. All copolyesters display excellent thermal stability and a glass transition temperature (Tg) up to 72 °C, decreasing slightly with the increasing amount of the nitro derivative content. Furthermore, these copolyesters revealed to be essentially amorphous materials. The hydrolytic degradation was investigated for all copolyesters at 37 °C and the oxidative degradation only for the copolyester containing theoretically equimolar amount c.a. PEBF50NI50.The oxidative degradation shows well weight loss up to 56wt.% after 15 days of incubation, confirmed by 1H NMR analysis published

The principal aim of this work is the development of a specific experimental device used to identify the intrinsic characteristics of a thread and to characterize the influence of the tapping process. Two turns of thread engagement were only considered. The geometry of the tapping thread was visually inspected on a cross section of thread. Two tests of the screw-nut assembly were carried out. The first one that was used for analyzing the internal shear of thread consists in applying an axial displacement on the screw mounted on a fixed nut. In the second test, a tightening torque was applied on a pressure screw assembly to investigate principally the interface shear behavior of thread. Experiments revealed that the internal shear results in three-step spread over five distinct phases. The interface shear was quantified by the identification of the friction coefficient which was determined from the load-tightening torque relationship. The evolution of the friction coefficient versus the number of cycles of clamping/unclamping was also established. Therefore, the tribological behavior of each specimen was highlighted through thread wear analysis. The results and discussions are presented by comparing the cut and form triangular ISO thread and by studying the effect of the initial tap hole diameter.

A new class of materials based on crosslinked poly (ester-urethane) containing low proportions of ionic liquid were synthesized using biobased sulfonated oligoester diol, trimethylol propane (TMP), 4,4′-methylene bis(cyclohexyleisocyanate) (HMDI) and 1-butyle-3-methylimidazolium acetate (BMIMAc). Sulfonated oligoester with a well-controlled molar mass was first obtained by melt polycondensation catalyzed by Ti(OBu)4. The resulting products were characterized by, 1HNMR, DSC and MALDI-TOF MS techniques. The systems of crosslinked poly (ester-urethane) and ionic liquid were obtained via a one-shot process. FTIR technical was used for a more effective control of crosslinking reaction. The Thermomechanical analysis of the resulting materials were performed by DSC and DMA technique. Furthermore, the hydrolytic and oxidative degradation study revealed that the degradation of systems mainly depends on the content in ionic liquid and the crosslinking degree of networks.

Polymer resins, such as polyester-, polyurethane- and alkyd resins are frequently applied as binder component in paints, printing inks, coatings or materials for additive manufacturing. Besides aliphatic building blocks with different chain lengths, cyclic monomers are used as starting materials, to increase the hardness of the resulting coatings materials. For this, mostly aromatic compounds derived from petrochemical sources, such as phthalic anhydride, isophthalic acid or terephthalic acid are being used. Monomers from renewable resources with similar chemical structures and chemical properties are scarce. In this study, (1R,3S)-(+)-camphoric acid is used as alternative building block for UV-curing polyester resins derived from itaconic acid and 1,6-hexanediol. The properties of both resins and final materials are compared to similar resins derived from isophthalic acid. In both cases, the incorporation of the cyclic monomer led to an increase in glass transition temperature, as well as viscosity of the resins. Thermal as well as mechanical properties of the cured materials were also improved in comparison to a resin without any cyclic building block incorporated.

High-glass transition thermoplastic polymers have dawned much attention in recent years due to their typical stiffness, enhanced thermal properties, and more importantly the emerging need to replace commercial fossil-based products by more sustainable alternatives, derived from renewable resources. In this regard we engineer here for the first time the design of wholly (hetero-)aromatic polyesters based on a key-platform chemical-2,5-furandicarboxylic acid (FDCA) and commercially-available catechol, or hydroquinone, whose structures were characterized by Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR). Both polymers had a high glass transition (Tg up to 167 °C) detected by differential scanning calorimetry (DSC) and has excellent thermal stability according to thermogravimetric analysis (TGA). The para- and ortho- substitution in hydroquinone and catechol, respectively, affected crystallinity, which was typically higher for poly(1,4-phenylene-2,5-furandicarboxylate) (PHQF) favouring a stiffer and close packing structure. Also, the thermal properties were higher for PHQF.

This study is carried out to assess the cardiopreventive effect of (E)-N'-(1-(7-methoxy-2-oxo-2H-chromen-3-yl) ethylidene)-4-methylbenzenesulfonohydrazide or SHC, a novel synthesized coumarin, against myocardial infarction induced by isoproterenol (ISO). The SHC compound was identified and characterized by spectral methods (infrared, 1 H NMR [nuclear magnetic resonance], 13 C NMR, Nuclear Overhauser Effect Spectroscopy, and high-resolution mass spectroscopy). Male Wistar rats were divided into four groups: Control, ISO (rats were injected subcutaneously by 85 mg/kg body weight [BW] of isoproterenol at Days 6 and 7 of the experience), ISO + SHC (150 µg/kg BW, orally for 7 days) and ISO + acenocoumarol (150 µg/kg BW, orally for 7 days). Results showed that ISO induced a remarkable alteration of electrocardiogram (ECG) pattern and increases of plasma cardiac troponin T, creatine kinase-MB, total cholesterol, triglycerides, low-density lipoprotein-cholesterol, lactate dehydrogenase, aspartate transaminase, and malondialdehyde. In addition, ISO reduced the high-density lipoprotein-cholesterol content and the activities of superoxide dismutase and glutathione peroxidase, with the induction of myocardial necrosis. However, SHC administration revealed a significant decrease in cardiac dysfunction markers, restored normal ECG pattern, as well as improving lipids parameters. Moreover, SHC treatment remarkably alleviated the cardiac oxidative stress and the myocardial remodeling process. Overall, the SHC offers good protection from acute myocardial infarction through the antioxidant capacity.

Recently, itaconic acid has drawn considerable attention as a novel radical-curing building block for polyester resins. These bio-based materials have been used in thermal, as well as ultra violet (UV) curing applications, such as printing inks or coatings. Poly(ester amide)s from itaconic acid could be very interesting, as the amide group could alter the properties of the resins as well as cured materials. However, standard polycondensation reactions with diamines are not possible with itaconic acid as the amines preferably react via an aza-Michael addition at the &alpha, &beta, unsaturated double bond. Therefore, alternative and more elaborate synthetic strategies have to be developed. Herein, we present two different synthetic strategies to poly(ester amide)s from itaconic acid that circumvent the addition reaction of the amines. This is in both cases done by a pre-reaction to form stable amide building blocks that are then reacted with itaconic acid or polyesters derived thereof. The structural composition and the properties of the resin are characterized, and the UV-curing reactivity is examined. All properties are compared to corresponding polyesters from itaconic acid.

Furano-Aliphatic copolyesters, such as poly(propylene furanic)-co-(polycaprolactone) (PPF-co-PCL), Poly(propylene furanic)-co-(polylactide) (PPF-co-PLA) and Poly(propylene furanic)-co-(polyglycolid...

The aim of this paper is to investigate the influence of the geometrical arrangement of acoustic pressure measurement sensors on the reconstruction of the unsteady rotating forces acting on the fluid by the fan’s blade. A development based on the tonal noise generated by an axial fan and validated with a directivity experience is used to derive a discretized form of the direct problem and to simulate acoustic pressures at known spatial positions in the radiated field. The inverse problem is usually ill-posed and requires optimization technique to stabilize the solution for small perturbations in the measured acoustic input data. The reconstruction shows that the inverse problem conditioning depends on the aeroacoustic source and the far-field sensor number and geometrical distribution as well as on the studied frequency. Tikhonov regularization can provide an appropriate regularization parameter leading to a satisfactory reconstruction of imposed unsteady rotating forces even in the presence of measurement noise. Simulations are conducted for three geometrical arrangements of microphones: line, arc of a circle and square.

The far-field acoustic pressure emitted by the unsteady rotating force acting by the fan on the fluid is computed using a tonal noise model prediction. Generally, the usefulness of any model depends in part on the accuracy and reliability of its output. Yet, because all models are imperfect abstractions of physical reality, and because precise input data are rarely if ever available, all output values are subject to imprecision. In this paper, the accuracy of the used tonal noise model prediction is easily influenced by the way in which the unsteady rotating force was modeled. To reach a good correlation between the numerical and experimental results, sensitivity and uncertainty analysis are conducted on the used model. The first one consists firstly on assigning to each model input the Sobol index. Then, according to the obtained index value, the most influential input is revealed. The second one leads to the assessment of uncertainties propagation through the model using the Monte Carlo simulation. Finally, the results from both analyses are presented and discussed.

A series of novel-sulfonated furanic polyesteramides have been synthesized by polycondensation in the melt-phase. The copolymers were obtained with reasonable molecular weights and high inherent viscosities between 0.2 and 0.4 dL/g. The hydrolytic degradability of polyesteramides was enhanced by the increasing of amide units in the copolymers backbone.

Novel copolyamide-imides containing furan moieties were prepared from the resulting furanic dihydrazides and pyridinic dihydrazides monomers with various aromatic dianhydrides. Their copolymers were prepared by applying a one sept melt polycondensation method at high temperature. The inherent viscosities of these copolymers are in the range 0.024–0.064 L/g. The copolyimide-imides furano-pyridinic are amorphous with Tg ranging from 95 to 152 °C and their thermal and hydrolysis stabilities are influenced by the presence of the pyridinic function. These copolymers having a good stability in the H2O2/CoCl2 medium.

Biobased aliphatic sulfonated oligoesters with 10 to 30% of sulfonated units were synthesized by melt polycondensation of biobased monomers such as diethyl succinate, z-octadec-9-enedioic acid, dimer fatty acid, sodium (sulfonated dimethyl succinate), and various diols like 1,4-butane diol and isosorbide. Structural characterization of the resulting oligoesters was determined by 1H NMR spectroscopy and MALDI-TOF MS technique. Showing a regular structure, the nature of the different expected species present in the macromolecular structure allowed the detection of etherification and cyclisation side reactions. The study of the thermal properties indicates that the resulting oligoesters are amorphous or semicrystalline that essentially depend on the nature of monomers. Films of oligoesters treated in acidic, basic, and natural media at 37°C indicate that the remaining weight depends essentially on the composition of oligoesters. Finally, sulfonated oligoester was used to prepare a biobased poly(ester-urethane) thermoset, a material having tunable properties.

A suitable process for modifying PVA with nicotinic acid to generate a graft copolymer was developed. The copolymers received as ligand were complexed with MnII and CoII ions. The coordination of this copolymer with the metal ion and the inclusion of nicotinic acid in the PVA copolymer was ascertained by FT-IR and NMR spectroscopy. EPR and UV–vis spectra of complexes indicates that CoII as square planar geometry and MnII as octahedral complexes. The adsorption of IC dye onto CoII/NA-PVA complex was noticeably greater (90%) than MnII/NA-PVA complexes. The DFT quantum chemical calculation was applied against the tested compounds. Optimization geometry and frontier molecular orbitals (FMOs) postulated that the charge transfer occurred from metal to ligands. The calculated NLOs properties for these polymers were higher character than reference material.

A straightforward substitution of non-renewable aromatic aliphatic copolyesters by renewable homologous furanic aliphatic copolyesters was successfully realized by copolymerization of furanic unit, aliphatic and 1,3-propanediol. Different copolyesters were synthesized and characterized by 1H-NMR, 13C-NMR, FTIR, DSC and TGA. For all copolyesters, the degree of randomness, determined by 1H-NMR, was close to 1, reflecting a random distribution of furanic and aliphatic ester units in polymer chains. The hydrolytic degradation of polymers was performed at pH 4.35 at 37°C over a period of four weeks. The hydrolytic degradation proved a mass loss of about 10%.

In order to prepare furanic–aliphatic polyesteramides without the side reactions taking place with furan-2-carboxylic acids or esters, a furan-based diamine, 5,5′-isopropylidenebis(2-furfurylamine), was reacted in the bulk, either with (i) ethanediol and dimethyl adipate or (ii) with the corresponding aliphatic polyester (polyethylene adipate). The polycondensation involves both amine–ester and hydroxy–ester interchanges, with elimination of excess ethanediol. High-molar-mass furanic–aliphatic polyesteramides were easily obtained. Method (ii) was more efficient than method (i), but no side reactions were observed with both methods. These polyesteramides behave as amorphous random copolymers.

The furan-maleimide Diels-Alder (DA) reaction was used to synthesize thermally reversible and biodegradable networks based on functionalized polyglycolic acid precursors. Hydroxyl-telechelic polyglycolic acid (PGA) with a well-controlled molar mass was first obtained by ring-opening polymerization (ROP) of glycolide catalyzed by Sn(Oct) 2 and using 1,4-butanediol as initiator. Functional furan polyglycolic acids with different functionalities were prepared by the isocyanate-alcohol condensation reaction from multi-alcohols such as glycerol and pentaerythritol, H 12 MDI, PGA-diol and furfuryl alcohol. For a more effective control of the DA reaction conversion and before approaching the synthesis of the networks, a Diels-Alder adduct and a coupling agent bearing maleimide functions on its extremities were synthesized separately. At different stages, the obtained products were characterized by FTIR, NMR, DSC and SEC techniques. The thermoreversible networks were then obtained via two different methods: first, one in which the Diels-Alder adduct gives rise to the networks (method 1) and then via a one-shot process where the alcoholysis reaction of the coupling agent is responsible for the crosslinking (method 2). Thermomechanical analyses were used to verify the thermal reversible character of PGA-based networks. Furthermore, biodegradability studies such as in vitro degradation as well as aerobic biodegradability revealed that an increase in the polymer crosslinking density and a decrease in glycolide content typically lead to a slower degradation.

The aim of this paper is to investigate an inverse method used to evaluate the unsteady rotating forces acting on the fluid by the fan’s blade. A simple model based on the tonal noise produced by an axial fan and validated with a directivity experience is used to derive a discretized form of the direct problem and to simulate acoustic pressures at known spatial positions in the radiated field. The inversion of this direct problem is ill-conditioned and requires a regularization technique to stabilize the solution for small perturbations in the measured acoustic pressures. The reconstruction reveals that the conditioning of the inverse problem depends on the aeroacoustic source and the far-field microphones number as well as on the studied frequency. Tikhonov regularization can provide an appropriate regularization parameter leading to an accurate reconstruction of imposed unsteady rotating forces even with the presence of measurement noise.

International audience; A series of furanic sulfonated copolyesters containing 20 mol.% of sodium sulfoisophthalate units were synthesized via a two-step melt polycondensation process from (5,5'-isopropylidene-bis(ethyl 2-furoate)) and (dimethyl 5-sodiosulfoisophthalate) with different diols: alkyl (1,2-ethanediol, 1,4-butanediol, 1,6-hexanediol) or ether (diethylene glycol and triethylene glycol). Structural characterization of copolyesters was deeply investigated by H-1 and C-13 (1D and 2D) NMR spectroscopy and by SEC. The results showed that the final structures not only depend on the initial monomers composition but also on the process which can induce at high temperature etherification and decarboxylation side reactions. For the alkyldiols series low molecular weights were obtained when side reactions occurred and when the monomer excess was difficult to remove from the reaction medium. Finally, it has been displayed that the modulation of dials composition allows for tuning copolyesters properties. Thus the copolyesters are amorphous with T-g ranging from 19 to 66 degrees C whereas their liquid water sorption and hydrolytic degradation resistance are in relation with the flexibility of the chain and their water accessibility to the ester linkages.

Solution polycondensation of furanic dihydrazides with different bridging groups, in conjunction with terephthaldehyde or isophthaldehyde, gave high yields of a novel series of furanic polyacylhydrazones with high molecular weights. The polymers were characterized by solubility tests, viscosity measurements, 1H and 13C NMR, FTIR spectroscopies and thermogravimetric analysis. The polyacylhydrazones obtained had inherent viscosities in the range of 0.52-1.21 dL/g, and were easily dissolved in common polar solvents. The glass-transition temperatures of these polymers were recorded between 201 and 232°C. Decomposition temperature for 10% weight loss all occurred above 352°C in nitrogen atmosphere.

International audience; New dialkynyl monomers containing furan and ester or amide units were prepared via three step reactions from ethyl furan-2-carboxylate. Their click polymerization with either poly(ethylene glycol) diazide or poly(tetrahydrofuran) diazide catalyzed by Cu(I) led to corresponding amorphous poly(ester triazole) and poly(amide triazole) with molecular weights in the range of (7-11) x 10(3) and with glass transition temperatures in the range of -35 and -19 degrees C. The temperature at 5% wt loss (T-10), determined from TGA of polyazomethines were in the range 345-365 degrees C indicating their good thermal stability.

Polyesteramides based on diethyl 5,5′-(propane-2,2-diyl)-bis(furan-2-carboxylate), a biobased diester, are synthesized by high temperature bulk polycondensation with mixtures of hexane-1,6-diamine and ethane-1,2-diol. The ester/amide ratio in final copolymers is governed by the initial diester/diamine ratio, any diol excess being eliminated during the synthesis via a series of interchange reactions. The copolyesteramides are thermally stable, amorphous compounds. Their structural characterization shows the existence of minor side reactions: diol etherification, and two reactions, specific to furan-2-carboxylate structure, the formation of nonreactive 2-furyl end groups and chain branching resulting from amidine formation by amide–amine condensation.

A series of new polyazomethines containing furan moieties was synthesized by polycondensation of bifuranic diamine monomers with commercially available aromatic dialdehydes viz., terephthaldehyde (TPA), isophthaldehyde (IPA). Inherent viscosities and number average molecular weights of polyazomethines were in the range 0.90–1.56 dL/g and 10460–17850 (SEC, polystyrene standard), respectively indicating formation of medium to reasonably high molecular weight polymers. The resulting polyazomethines were characterized by solubility tests, viscosity measurements, FTIR, NMR, UV spectroscopy, differential scanning calorimetric (DSC), and thermogravimetric analysis (TGA). These furan-based polyazomethines were essentially amorphous and exhibited glass transition temperatures (Tg) in the 150–190°C range. The temperature at 10% wt loss (T10), determined from TGA of polyazomethines were in the range 300–380°C, indicating their good thermal stability.

International audience; Polymers from renewable resources are of high interest since it could be possible to valorize the biomass and in parallel to tune their macromolecular structures in relation with their properties. Here novel bisfuranic-pyridinic copolyesters, namely poly (ethylene furoate-co-ethylene pyridinate) (PEBF-co-PEPy) were prepared by applying a two-stage melt polycondensation method at high temperature, in a presence of titanium derivatives as catalyst. Molecular weights of resulting copolyesters are in the range 24000-45200 g mol(-1) and their chemical microstructures statistical as shown by NMR. These furanopyridinic copolyesters are amorphous with Tg ranging from 62 to 67 degrees C and their thermal and hydrolysis stabilities are influenced by presence of the pyridinic dyads Py-ED-Py. Finally the oxidative degradation in H2O2/CoCl2 cannot be effective because of the chelating properties of pyridinic moieties.

Poly(e-caprolactone) (PCL)-based thermoreversible networks with self-healing properties were prepared through Diels- Alder (DA) and retro-DA reactions. Bis- or Tris-maleimide compounds and a series of copolymer(caprolactone-diene) PCLXFY (X: degree of polymerization and Y: furan-average functionality) with Y between 2.4 and 4.9 were used. The successive sequences of for- mation and dissociation of polycaprolactone networks via DA and retro-DA reactions were observed repeatedly by dynamic mechani- cal analyses (DMA) and their gel-temperatures determined. The cross-linking densities, thermal properties, and thermal reversibility of the PCLXFY/multimaleimide polymers have been modulated by the structure and functionalities of the used diene and dienophile moieties. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 000: 000-000, 2012

The current techniques for monitoring and diagnostics of rotating machines to their conditional predictive maintenance mainly are based on vibration monitoring. In this research, experimental and theoretical methods to predict the tonal noise of a faulty fan are developed and validated. These methods can be used on identifying defects of an axial fan based on an acoustic monitoring in situations where it is necessary to operate remotely due to the inaccessibility of the areas of event defects.

5,5'-Isopropylidene-bis(ethyl 2-furoate), a monomer prepared from bio-based ethyl 2-furoate, was reacted with dimethyl terephthalate and ethan-1,2-diol (ED) by melt polycondensation in order to obtain copolyesters containing both terephthalate and furoate units. The conventional two-step method involving (i) the formation of a hydroxyethyl-terminated oligomer by reaction of starting diester mixture with excess ED and (ii) a polycondensation step with elimination of ED was used to obtain high molar mass copolyesters. Copolymers of various compositions were synthesized and characterized by 1 H NMR, DSC, and TGA. For all compositions, the degree of randomness, determined by 1 H NMR, was close to 1, reflecting a random distribution of terephthalic and furanic ester units in polymer chains. The resulting materials are amorphous polymers (Tg = 70-80 °C) with good thermal stability.

2-Furamide was treated with an excess of paraformaldehyde in an acidic medium to promote both its oxymethylation and the subsequent polycondensation of the reaction product involving the C5 position of the heterocycle. The molecular weight of ensuing 2,5-furanmethylene polyamide was optimised by examining the role of the synthetic procedure, the catalyst and medium used and the reaction temperature.

A two-step transesterification procedure was applied to combinations of difuranic diesters and both aliphatic and furanic diols. The reaction parameters (including the nature of the catalyst) were varied in both phases of the process and the results compared with those published for similar systems based on aromatic diesters. The best results related to the first phase of the synthesis were obtained using Zn(AcO) 2 , Pb(AcO) 2 or Ti(OBu) 4 at 200°C with a large excess of diol. The second phase, which led to the actual polymer at 200-240°C, called upon the catalytic action of SnC 2 O 4 , Sb 2 O 3 and Ti(OBu) 4 and was prolonged until the viscosity of the media ceased to increase. Specific problems, related to some fragile moieties, limited the success of these polymerizations to a number of combinations which gave polyesters bearing regular structures and molecular weights in the tens of thousands.

The research conducted in this thesis was achieved in the context of vegetal biomass valorization. It aims to develop a new family of aliphatic oligoesters from biobased monomers and incorporating into their structure sulfonated groups. This choice is justified by the following three considerations. (i) This is a contribution to the valorization of vegetal biomass. (ii) The presence of sulfonated units in the structure of this type of polymers gives them specific physicochemical properties favoring their use in various industrial sectors. (iii) These oligoesters can be subsequently used for the preparation of poly (ester-urethane) networks and ionic liquid-based composites with potentially interesting thermomechanical properties and a great tendency towards hydrolytic degradation., La transformation de la biomasse végétale en composés simples pouvant servir comme monomères pour l’élaboration de nouveaux matériaux polymères susceptibles de se substituer à leurs homologues d’origine pétrochimique a été l’un des thèmes de recherche développés au cours des deux dernières décennies. c’est dans ce vaste contexte que s’inscrivent les travaux rapportés dans ce mémoire dont l’objectif était d’élaborer une nouvelle famille d’oligoesters aliphatiques en partant de monomères biosourcés et en intégrant dans leur structure des groupes sulfonés. Cette orientation est justifié par les trois considérations suivantes (i) cela constitue une contribution à la valorisation de la biomasse végétale (ii) la présence des unités sulfonés dans leur structure leur confère des propriétés physico-chimiques particulières favorisant leur utilisation dans divers secteurs industriels. (iii) Ces oligoesters peuvent être par la suite utilisés pour la préparation des composites à base de réseaux de poly (ester-uréthane) et de liquide ionique ayant des propriétés thermomécaniques potentiellement intéressantes et une grande tendance à la dégradation hydrolytique.

The research conducted in this thesis was achieved in the context of vegetal biomass valorization. It aims to develop a new family of aliphatic oligoesters from biobased monomers and incorporating into their structure sulfonated groups. This choice is justified by the following three considerations. (i) This is a contribution to the valorization of vegetal biomass. (ii) The presence of sulfonated units in the structure of this type of polymers gives them specific physicochemical properties favoring their use in various industrial sectors. (iii) These oligoesters can be subsequently used for the preparation of poly (ester-urethane) networks and ionic liquid-based composites with potentially interesting thermomechanical properties and a great tendency towards hydrolytic degradation.; La transformation de la biomasse végétale en composés simples pouvant servir comme monomères pour l’élaboration de nouveaux matériaux polymères susceptibles de se substituer à leurs homologues d’origine pétrochimique a été l’un des thèmes de recherche développés au cours des deux dernières décennies. c’est dans ce vaste contexte que s’inscrivent les travaux rapportés dans ce mémoire dont l’objectif était d’élaborer une nouvelle famille d’oligoesters aliphatiques en partant de monomères biosourcés et en intégrant dans leur structure des groupes sulfonés. Cette orientation est justifié par les trois considérations suivantes (i) cela constitue une contribution à la valorisation de la biomasse végétale (ii) la présence des unités sulfonés dans leur structure leur confère des propriétés physico-chimiques particulières favorisant leur utilisation dans divers secteurs industriels. (iii) Ces oligoesters peuvent être par la suite utilisés pour la préparation des composites à base de réseaux de poly (ester-uréthane) et de liquide ionique ayant des propriétés thermomécaniques potentiellement intéressantes et une grande tendance à la dégradation hydrolytique.

The research conducted for the preparation of this thesis aims to develop new thermoreversible and biodegradable polyglycolic-acid (PGA) based networks and polylactic-acid (PLA) based hydrogels, from polymers chemically modified by means of furanic, and maleimide cycle. The cross-linking of PGA to develop thermoreversible and biodegradable networks via the Diels-Alder reaction has been done by following two strategies and was the first part of this work. The aim was, among other things, to enhance the PGA by leading to reticulated structures with required mechanical properties while improving its stability properties. Hybrid networks of PLA / PEG and PLA / PHEMA were then synthesized in the melt by adopting the Diels-Alder reaction as a crosslinking mechanism. Once obtained, their contact with water leads to the formation of hydrogels. NMR structural analyzes confirmed the formation of expected structures. The thermoreversibility of the obtained networks has been shown by rheological analyzes. The morphology of the gels before and after swelling was analyzed by Scanning Electron Microscopy. The degradability of prepared networks was examined in two modes: hydrolytic and aerobic by microorganisms.; Les travaux de recherche réalisés, dans le cadre de la préparation de cette thèse ont pour objectif l’élaboration de nouveaux réseaux thermoréversibles biodégradables à base de polyglycolide (PGA) et d’hydrogels à base de polylactide (PLA) modifiés chimiquement au moyen du noyau furanique et du cycle maléimide. La réticulation du PGA, en suivant deux stratégies, en vue d’élaborer des réseaux thermoréversibles et biodégradables via la réaction de Diels-Alder a fait l’objet de la première partie de ce travail. Le but était entre autres de valoriser le PGA en conduisant à des structures réticulées avec des propriétés mécaniques requises tout en améliorant ses propriétés de stabilité. Des réseaux hybrides de PLA/PEG et PLA/PHEMA ont été ensuite synthétisés en phase fondu en adoptant la réaction de Diels-Alder comme mécanisme de réticulation. Une fois obtenus, leur mise au contact de l’eau conduit à la formation d’hydrogels. Les analyses structurales menées par RMN ont permis de confirmer la formation des structures attendues. La thermoréversibilité des réseaux obtenus a été montrée par des analyses rhéologiques. La morphologie des gels avant et après gonflement a été analysée par Microscopie Electronique à balayage. La dégradabilité des réseaux préparés a été examinée selon deux modes : hydrolytique et par les microorganismes en milieu aérobie.

The research conducted for the preparation of this thesis aims to develop new thermoreversible and biodegradable polyglycolic-acid (PGA) based networks and polylactic-acid (PLA) based hydrogels, from polymers chemically modified by means of furanic, and maleimide cycle. The cross-linking of PGA to develop thermoreversible and biodegradable networks via the Diels-Alder reaction has been done by following two strategies and was the first part of this work. The aim was, among other things, to enhance the PGA by leading to reticulated structures with required mechanical properties while improving its stability properties. Hybrid networks of PLA / PEG and PLA / PHEMA were then synthesized in the melt by adopting the Diels-Alder reaction as a crosslinking mechanism. Once obtained, their contact with water leads to the formation of hydrogels. NMR structural analyzes confirmed the formation of expected structures. The thermoreversibility of the obtained networks has been shown by rheological analyzes. The morphology of the gels before and after swelling was analyzed by Scanning Electron Microscopy. The degradability of prepared networks was examined in two modes: hydrolytic and aerobic by microorganisms., Les travaux de recherche réalisés, dans le cadre de la préparation de cette thèse ont pour objectif l’élaboration de nouveaux réseaux thermoréversibles biodégradables à base de polyglycolide (PGA) et d’hydrogels à base de polylactide (PLA) modifiés chimiquement au moyen du noyau furanique et du cycle maléimide. La réticulation du PGA, en suivant deux stratégies, en vue d’élaborer des réseaux thermoréversibles et biodégradables via la réaction de Diels-Alder a fait l’objet de la première partie de ce travail. Le but était entre autres de valoriser le PGA en conduisant à des structures réticulées avec des propriétés mécaniques requises tout en améliorant ses propriétés de stabilité. Des réseaux hybrides de PLA/PEG et PLA/PHEMA ont été ensuite synthétisés en phase fondu en adoptant la réaction de Diels-Alder comme mécanisme de réticulation. Une fois obtenus, leur mise au contact de l’eau conduit à la formation d’hydrogels. Les analyses structurales menées par RMN ont permis de confirmer la formation des structures attendues. La thermoréversibilité des réseaux obtenus a été montrée par des analyses rhéologiques. La morphologie des gels avant et après gonflement a été analysée par Microscopie Electronique à balayage. La dégradabilité des réseaux préparés a été examinée selon deux modes : hydrolytique et par les microorganismes en milieu aérobie.