Дисертації з теми "Mousses polyuréthane"
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Boukrim, Amale. "Mousses de polyuréthane à l’eau." Thesis, Pau, 2011. http://www.theses.fr/2011PAUU3033/document.
Повний текст джерелаBecause of their properties (low density, insulation, impact resistance. . . ), polymer foams are widely used. This work focused on polyurethane foams aims at : replacing physical blowing agents (CFCs, HFCs) by the carbon dioxide formed by the reaction of isocyanate and water & trapping a catalyst in the polyurethane network. The formation of water-blown polyurethane foams involves two reactions. The polymerization (or gelling) reaction which creates the polyurethane network. And the blowing reaction which generates carbon dioxide. A proper balance is required between the two reaction rates to obtain a foam with atisfactory properties. The kinetics of each reaction considered separately was studied. Thus, on one hand IRFT and rheology were used to study the kinetic of the polyurethane formation. Both linear and crosslinked polyurethane were studied. We showed the interest of using utanediol to control the structure of the linear polyurethane. The effect of temperature and nature and concentration of catalyst on the kinetics of polymersation was showed. Moreover, triethanolamine which contains amine groups ( catalyst) and hydroxyl groups (crosslinkingagent) was tested. One the other hand, an appartus was made to study the kinetic of the blowing reaction. We show that the following parameters : temperature, weight of the diisocyanate, nature and concentration of catalyst, have a relatively limited influence on the kinetics of release of carbon dioxide. A study of polyurethane foams based on a commercial fomulation showed that it is possible to replace the physical blowing agents by water
Saint-Michel, Fabrice. "De l'élaboration aux propriétés mécaniques de mousses polyuréthane composites." Grenoble INPG, 2004. http://www.theses.fr/2004INPG0026.
Повний текст джерелаPaget, Baptiste. "Étude du renforcement de mousses syntactiques à matrice polyuréthane." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1202.
Повний текст джерелаSyntactic foams synthesized from an elastomeric matrix and soft-shell microspheres have shown interesting acoustical properties. They open new perspectives for the manufacturing of stealthy submarines or ships, but the industrialization of such material is held back by their great compressibility: hydrostatic pressure tends to crush the microspheres, which leads to a loss of the damping properties. We are therefore interested in studying the reinforcement of syntactic foams with polyurethane matrix. Scientific literature being scarce on this subject, a reference syntactic foam has been synthesized in the laboratory to allow a better characterization of this material and its components. In particular, an innovative test of hydrostatic compression has been developed to characterize the behavior under pressure of the microspheres and foam. A model of the literature simulating the compression of syntactic foams has been used thanks to the material parameters collected; it allowed us to test the influence of various parameters on this compression. This model could also predict the characteristics of the components of a foam whose compressibility would meet a set of specifications. These different analyses have shown that the main parameter governing the compression of syntactic foams is the Young's modulus of the matrix. In addition, a compression reinforcement can only be obtained using a chemical reinforcement of the matrix; the presence of fillers (fibers, MWCNTs) does not bring significant changes
Talal, Cheikhalard. "Synthèse de polyuréthane macroazoamorceurs (PUMAI) et leur utilisation pour préparer des copolymères à blocs polyuréthane-b-polyvinyle : applications dans le domaine des adhésifs et matériaux composites." Lyon, INSA, 1997. http://www.theses.fr/1997ISALO111.
Повний текст джерелаIn this work, the synthesis of polyurethane macroazo initiators (PUMAI) based on 2,2' azobis (2-cyanopropanol) (ACP) was investigated for the synthesis of thermoplastic and thermoset block copolymers. The study of the structure and reactivity (radical initiation ability and condensation with Isocyanates) of ACP showed that this molecule is very useful for the elaboration of PUMAI. Before block copolymers elaboration, we have studied the two stages of PUMAI synthesis. This synthesis was possible in solution with stannous catalyst at low temperature. From PUMAI, poly(urethane-b-styrene) and poly(urethane-b-methyl methacrylate) were elaborated, fractwnated and characterized in both structural and mechanical point of view. PUMAIs were also used for cross linking of unsaturated polyesters/styrene resins. They are able to Imitate radical polymerization and to reduce shrinkage (in order to be used instead of some. Low shrink or low profile additives as polyvinyl acetate and some polyurethanes). They are linked by covalent bond to the poly( ester/styrene) ma tri x after cross linking with or without fillers (glass fibers). Ali analyses realized on block copolymers and composites "poly(ester/styrene/urethane)/glass fibers" have shown that the block efficiency of PUMAIs is about 50% and proved their interest m the block copolymers synthesis
Sabbahi, Abdelaziz. "Transfert de l'eau dans la mousse de polyuréthane à 80 et 100°C : modélisation et expérimentation." Saint-Etienne, 1993. http://www.theses.fr/1993STET4019.
Повний текст джерелаPellizzi, Eleonora. "Etude du vieillissement des mousses de polyuréthane ester et consolidation par les aminoalkylalkoxysilanes." Thesis, Evry-Val d'Essonne, 2012. http://www.theses.fr/2012EVRY0034/document.
Повний текст джерелаMuseum artifacts made of polyurethane foam are frequently affected by conservation issues mainly related to the loss of their mechanical properties. While effective polyurethane ether foam treatments already exist, no convenient consolidationtreatment exists for polyurethane ester foams. The possibility of a reinforcement effect expected to prevent the mechanical properties loss of new foams and the structure collapse of degraded foams has been evaluated. Two aminoalkylalcoxysilanes (AAAS), the 3-Aminopropylmethyldiethoxysilane and the N-(2-Aminoethyl)-3-aminopropylmethyldimethoxysilane, which gave promising results for consolidation of paper, have been tested on modern industrial flexible polyurethane ester foam samples. The behaviour of the reference polyuréthane foam to artificial aging hasbeen monitored and compared to naturally aged polyuréthane foams. Then, AAAS solutions at different concentrations have been applied, by immersion, on unaged and artificially aged polyurethane ester foam samples. Mechanical properties havebeen studied by Compression Force Deflection Test, which shows that after AAAS treatment the resistance of the foam to compression improves. The AAAS distribution in the thickness of the samples has been investigated by Fourier TransformInfrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Magic angle spinning nuclear magnetic resonance (MAS NMR) has been used to confirm AAAS polymerization and to evaluate its average polymer chain length. The promising results obtained suggest that AAAS could be an efficient solution for the consolidation of polyurethane ester foam for both a preventive treatment and a restoration treatment
Thoinon, dit Boisson Catherine. "Mise au point de formulations hybrides polyester polyuréthane répondant aux spécifications actuelles du procédé SMC." Lyon, INSA, 1990. http://www.theses.fr/1990ISAL0039.
Повний текст джерела[The interest of these SMC formulations concerned the thickening reaction involving a hydroxyl terminated polyester resin and a diisocyanate. The results demonstrated the feasibility of isocyanate thickening of polyester resins : the viscosity rise was better controlled, reproducible and faster. The use of a short diol which is known to be a chain extender, with polyester resin and diisocyanate produced hard-segment sequences of various lengths. The average length depended on the polymerization conditions and the ratio of diol. It influenced the properties of the final material : in particular using a hight ratio of diol, good impact and profile surface results were obtained for industrial moulded parts. In order to understand the mechanisms of reaction during the viscosity rise, we have studied formulations using model resins. We demonstrated that the critical phenomena we observed, is the result of gellation. We suggested that gellation is due to a hydrogen bonding-type association of the polymer chains. At the early stage of gellation, phase separation by spinodal decomposition could take place occurring at a critical length of hard-segment sequences. Then gellation by percolation through hydrogen bonding followed in the polymer-rich region]
Le, Bail Jean-Baptiste. "Modélisation du comportement mécanique sous chargement d’une butée d’amortisseur en mousse de polyuréthane : vers une démarche de dimensionnement en fatigue." Electronic Thesis or Diss., Brest, École nationale supérieure de techniques avancées Bretagne, 2022. http://www.theses.fr/2022ENTA0003.
Повний текст джерелаPolyurethane foam jounce bumpers are widely used in the automotive industry. Their main function is to absorb vertical shocks to the wheels and contribute to the integrity of the vehicle suspension. The mechanical response of this type of parts implies to take into account different mechanisms, from the buckling of the walls of the part to the self-contact through the geometrical non-linearities. The current characterization of these polyurethane foam jounce bumpers in fatigue is currently limited to the customer’s specifications and to the tests predefined by him. The objective of this thesis is to carry out a complete experimental characterization of the mechanical behavior in order to identify an Hyperfoam type behavior law. This characterization is also based on imaging techniques, SEM and tomographic, in order to characterize the link between the microstructure and the mechanical behavior of the jounce bumper. This study should allow to define a global approach for the fatigue design of polyurethane foam jounce bumper
Duboeuf, Olivier. "Contribution à l'optimisation du confort dynamique de sièges automobiles par la compréhension des mousses de polyuréthane." Thesis, Mulhouse, 2017. http://www.theses.fr/2017MULH9758.
Повний текст джерелаThe improvement of comfort in the automotive industry is a major challenge for car manufacturers and suppliers. At the heart of these concerns is the base seat system, major interface between the occupant and the vehicle vibration environment. This dissertation deals with the study of the main car seat sub-component: polyurethane foam.A wide range of polyurethane foam samples have been molded for a design of experiments according to selected process parameters. Several experimental protocols were employed to determine their physical properties, mechanical quasi-static and dynamic characteristics. A new protocol and an innovative device have been designed to characterize the foam sample submitted to vibrations. Statistical and principal components analysis helped to highlight existing correlations between those properties.A rheological model, adapted to the application in an industrial context, was carried out. For this purpose, a comparative study of the performance of different models applied to various polyurethane foam samples was conducted.To extrapolate the results on foam samples to a complete seat, additional tests have been performed with different formulations in both quasi-static and dynamic studies.The analysis of process parameters, physical properties and quasi-static and dynamic behaviors allowed highlighting of the links between these different features. Thus, it becomes possible to design a foam pad with predicted properties and minimize the time to design a car seat
Gossiaux, Alexandre. "Comportement au feu de mousses polyuréthanes rigides : Approches systématiques." Electronic Thesis or Diss., Centrale Lille Institut, 2021. http://www.theses.fr/2021CLIL0021.
Повний текст джерелаA common awareness of environmental factors and more particularly of global warming makes it urgent to better control energy consumption. One solution is to reduce energy loss in building using new and efficient thermal insulation materials such as polymeric foams. Polyurethane (PUR) and polyisocyanurate (PIR) foams are very effective and competitive materials due to their low cost. However, these materials are extremely flammable due to their organic nature. Researchers and manufacturers add molecules called flame retardants (FRs) to their composition in order to prevent the outbreak of a fire or reduce the intensity of combustion when a fire breaks out. The objective of this PhD work is to study by systematic approaches the fire behavior of PUR and PIR foams. The aim is to propose a scientific approach allowing a quicker and more efficient development of new formulations. This systematic study was also coupled with a multi-scale study of the fire behavior of the foams, as a laboratory-scale fire test was developed (M-SBI), which allowed a quick and efficient examination of the formulations. The FRs studied in this work are phosphorus organic FRs which are currently promoted to replace some halogenated FRs which could be dangerous for the environment and health. The mechanisms of degradation of virgin and flame retarded foams were elucidated using various analytical tools. Thus, in the case of phosphorus FRs, we were able to demonstrate that their mode of action varied according to the phosphorus oxidation degree as well as according to their point of decomposition. Moreover, the efficiency of the FRs also varies according to the foam used (PUR or PIR). All these results can thus advantageously be exploited to propose future efficient flame retardants for specific systems to reduce the combustion intensity of the foams
Sfaoui, Abdelkader. "Mesure des paramètres viscoélastiques de la mousse de polyuréthane dans le cadre de l'étude de la propagation acoustique." Lille 1, 1993. http://www.theses.fr/1993LIL10074.
Повний текст джерелаLefebvre, Louis. "Développement et caractérisation de mousses cellulaires élastomères pour l’intensification des procédés." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1028/document.
Повний текст джерелаSolid foams, made with polyurethane, are well known for their interesting transport properties such as low pressure drop or high specific surface area. However, there are not used as catalytic support due to actual deposition method which causes an alteration of their mechanical properties. First, we used a new deposition method using polydopamine (PDA), a polymer with interesting adhesive and reducing properties. The PDA layer will cover homogenously our support then will act as intermediary for active phase deposition, whether they are commercially available or synthetized in-situ. Afterward, our supports were tested for several catalytic reactions, whether monophasic (liquid phase) or biphasic (gas/liquid) to show the active phase efficiency and stability. Furthermore, we successfully deposited a good active phase (cobalt) for hydrogen production. Kinetic study at low temperature were done and shown promising results for sustainable energy production. Finally, the last part was devoted to the use of our soft structured catalytic support within a new reactor, allowing to use its mechanical properties to improve mass transfer
Ju, Minglei. "Contribution à la modélisation du comportement visco-hyper-élastique de mousses de polyuréthane : Validation expérimentale en quasi-statique." Thesis, Mulhouse, 2014. http://www.theses.fr/2014MULH8865/document.
Повний текст джерелаFlexible polyurethane foam is widely used in numerous applications such as acoustic, thermal and building due to its low density and its ability to absorb thermal and acoustic energy. It is also used for the comfort of the seats such as the vehicle, train, plane due to its low stiffness and its ability to absorb deformation energy. In order to optimize the comfort of the car seat, it is necessary to model the behavior of seat system, particularly the flexible component - polyurethane foam. The main objective of this study is to identify and model the quasi-static behavior of polyurethane foam under different test conditions in large deformations. Compression / decompression uniaxial unicycle and multicycle tests were carried out on three types of polyurethane foam at different strain rates, which allows us to understand the behavior of the material. The results of the tests indicate that the polyurethane foams exhibit a hyperelastic behavior and a viscoelastic behavior under large deformations. They also showed that the polyurethane foams have a stress softening phenomenon which is called 'Mullins effect' during the compression / decompression multicycle tests. In other words, the stress in first cycle is lower than the stresses in the subsequent cycles in the same deformation. ‘Mullins effect’ for the polyurethane foam is also an important study in this dissertation. Based on the experimental results and the goal of modeling quasi-static behavior of the polyurethane foam, three visco-hyperelastic models were developed. These models consist in two elements: hyperelastic models, which is normally used for description the behavior of rubber materials, and entire memory model which takes into account the history and describing the viscoelastic behavior. Model parameters were identified using appropriate identification and optimization methods. The results of modeling the mechanical behavior of the foam on the unicycle and multicycle tests were compared with experimental results. The models showed a very good competence to simulate the first cycle and the following cycles during the charge / discharge tests. Our models have proven its ability to model Mullins effect on flexible polyurethane foams. These models have been validated on three types of foam in order to present a comparative study of their effectiveness and their representativeness
Lefebvre, Jérôme. "Modélisation et simulation de la dégradation thermique de mousses de polyuréthane : application à la compréhension de leur comportement au feu." Lille 1, 2003. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2003/50376-2003-161.pdf.
Повний текст джерелаTejeda-Ricardez, Jesús Alberto. "Etude de la liquéfaction de déchets de l'industrie de l'huile d'olive en vue d'une application dans le domaine des résines phénoliques et des mousses de polyuréthane." Toulouse, INPT, 2004. http://www.theses.fr/2004INPT001G.
Повний текст джерелаChen, Xinyi. "Polyuréthanes à base de tannins et de glucides sans isocyanate (NIPU) pour adhésifs, mousses et finitions." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0286.
Повний текст джерелаThis research was focus on bioresources, including tannin, lignin, soybean protein, humins, to prepare bio-based wood adhesives and foams. There are four main parts, including two kinds of wood adhesives preparation by using bio-resources, i.e., bio-sourced NIPU wood adhesives and bio-based (tannin, SPI, and lignin) wood adhesives without toxic formaldehyde; two kinds of tannin-foam products, i.e., typical tannin-furanic foam and non-isocyanate polyurethane foams. (1) Commercial humins, soybean protein isolation (SPI), and mimosa tannin have been utilized to prepare wood adhesives, based on the formulation of non-isocyanate polyurethanes (NIPU). The basic properties of the adhesives were determined. Techniques such as MALDI-ToF and FTIR were used to detect the products obtained and for analyzing the reaction mechanisms involved. Thermomechanical analysis (TMA) was utilized to investigate the thermal behavior of the adhesives. Finally, the laboratory plywood or particleboard were prepared for evaluating the bonding performances of adhesives. (2) A novel biomass-based wood adhesive was prepared with commercial mimosa tannin extract and glycerol diglycidyl ether (GOE) by convenient mechanical mixing. GOE served as the crosslinker of the tannin without any aldehyde addition yielding hardened threedimensional networks. Oifferent weight ratios of tannin/GOE were investigated by several techniques to determine their influence on final properties. Two kinds of lignin-based adhesives were prepared, i.e., ( i ) glyoxal modified lignin and dialdehyde starch cross-linked by urea; ( ii ) periodate oxidation by two-steps. The molecular species formed and the reactions mechanism involved were determined by FT-IR, 13C NMR and MALDI-ToF mass spectrometry. The adhesives based on this reaction were tested by bonding laboratory plywood or particleboard, by differential scanning calorimetry (DSC), and thermomechanical analysis (TMA). (3) A tannin-based non-isocyanate polyurethane (NIPU) rigid foam was obtained. Citric acid and glutaraldehyde mixture served as a blowing and crosslinker agent used to provide foaming energy and cross-link the tannin-based resin to prepare the NIPU foams. The reaction mechanism of the tannin-based NIPU foams were investigated by FT-IR, MALDI-TOF, and 13C NMR. Additionally, tannin was also used as a natural tire-retardant to improve the final properties of glucose-based NIPU foams, including fire retardancy and compression strength. (4) A biorefinery waste, humins, and soybean protein insolate (SPI) were selected as formaldehyde substitute bio-sourced crosslinkers for two kinds of tannin-based foam formulations. As expected, the properties were improved by using these bio-sourced crosslinkers. The basic properties of series tannin foams were investigated. The morphology and structure characteristics were observed by scanning electron microscopy (SEM). Additionally, the crosslinking reaction mechanisms between tannin with the two bio-sourced crosslinkers, i.e., humins and SPI, were determined by MALDE-ToF and FTIR spectrometry. Finally, the thermal stability, mechanical properties, fire retardancy and formaldehyde emission were evaluated by the relevant techniques
Thébault, Marion. "Développement de trois différents types de matériaux innovants à base de tannins." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0202/document.
Повний текст джерелаTannins are chemical extracts which represent a natural alternative to chemicals as phenol or resorcinol which are from oil resources. They are already used industrially for the synthesis of adhesives used for the manufacture of wood-based products such as particleboards and plywood, but generally always used with formaldehyde as a hardener to improve their mechanical strengths. The first products developed in this thesis are adhesive resins for the manufacture of particleboards, synthesized from Radiata Pine tannins and less hazardous aldehydes obtained by reacting sunflower oil with ozone then with a reducing agent. The study has focus first on the conditions of the ozonolysis, whose parameters are numerous, and the analysis of the oils obtained, then on the synthesis of resins with solutions of tannins. Some of these resins have been used to manufacture particleboards that have been tested in dry internal bond strength. Then the subject has been oriented toward the development of rigid tannin/furanic-based foams as part of an industrial multi-material project. Several formulations have been tested to achieve the objectives of a specification, whose first purpose is to obtain foam panels homogeneous, low in density and with good mechanical properties. The innovation has been to make these foams in a particleboard press. Finally, a new route to manufacture tannin-based polyurethane polymers has been tested by using less hazardous chemicals in replacement of isocyanates, conventionally used in the industry. The synthesis is made by a first carbonatation step of tannins hydroxyl groups and then by a reaction with hexamethylenediamine. Spectrometric analyzes have shown that the products obtained do have urethane linkages. The study led to the exploration of the use of tannins reacted with ammonia to replace hexamethylenediamine to obtain new "non isocynates" polyurethanes with more bio-based and environment-friendly chemicals
Barbara, Imane. "Synthèse de polymères macroporeux par polymérisation par étape en émulsion concentrée." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0045/document.
Повний текст джерелаPolyHIPEs are cellular materials obtained by polymerization within HIPEs « High Internal Phase Emulsions ». The polymerization occurs in the continuous phase of the emulsion allowing the creation of a solid matrix. The dispersed phase induces the porosity. PolyHIPEs are generally obtained by free-radical polymerization which restricts the choice of monomers. The majority of high performance polymers are obtained by polycondensation therefore it will be a great interest to enhance the variety of polyHIPEs available by using this technique. The objective of this work consists to synthetize polyHIPEs using polycondensation or polyaddition. Performing a step-growth polymerization within emulsion is a great challenge because this kind of reaction requires conditions generally incompatible with the stability of HIPEs. In the context of this work, we focused on the synthesis of polyurethane and polyester polyHIPEs. The homogeneity of the morphology of the materials was studied by varying several parameters, such: the nature of the emulsion (aqueous or non-aqueous, stabilized by surfactants or particles), the nature of the catalysts and the polymerization techniques. This work opens the access for the first time to polyurethane and polyester polyHIPEs. The results obtained are a starting point for further development in this field
Wronski, Maciej. "Couplage du contact et du frottement avec la mécanique non linéaire des solides en grandes déformations : application à l'étude des blocs de mousse en polyuréthane." Compiègne, 1994. http://www.theses.fr/1994COMPD712.
Повний текст джерелаRattanapan, Suwat. "Preparation and Properties of Bio-Based Polyurethane Foam Prepared from Modified Natural Rubber and Poly(ε-caprolactone)". Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1036/document.
Повний текст джерелаThe aim of this research was to prepare a bio-based polyurethane foam (PUF) containing hydroxyl telechelic oligomers from natural rubber (HTNR) and waste tire crumbs (HTWT) and polycaprolactone diol (PCL) as soft segments. The studied parameters included type of polyols and molar ratio between HTNR/PCL and HTWT/PCL. The molecular weight of HTNR and HTWT derived from 1H-NMR spectra were 1,800 and 1,400 g/mol, respectively. The molecular weight of PCL diol was 2000 g/mol. The effect of HTNR/PCL and HTWT/PCL molar ratio (1/0, 1/0.5, 1/1 and 0.5/1) on the foam formation rate and physical and chemical properties of the resulting PUF was investigated. The chemical structure of HTNR, HTWT and PUF were confirmed by FTIR and 1H-NMR. PCL diol provided faster reaction, thus higher PCL diol content showed higher foam formation rate. The foam density slightly changed with the molar ratio whereas the specific tensile strength of all samples was in the same range. The average diameter of cell increased with increasing contents of PCL diol. The addition of PCL diol resulted in reduced elongation at break and compressive strength. The cellular structure observed by SEM micrographs of HTNR based foams showed an almost closed cell. The biodegradability was assessed according to a modified Sturm test. Low density polyethylene and sodium benzoate were used as a negative and positive control sample, respectively. PUF samples showed an induction time of 33 days in which the percentage of biodegradation was 7-11%. The biodegradation of PUF containing only HTNR was 8.4% and 31.89% at 28 days and 60 days of testing respectively whereas the PUF containing 1/0.5 HTNR/PCL (by mole) showed a higher biodegradation: 11.31% and 45.6% at 28 days and 60 days of testing respectively. The molar ratio of HTWT/PCL strongly affected the kinetic rate of foam formation and foam morphology. According to SEM micrographs, polyhedral closed cells were observed. The addition of the PCL diol increased the thermal degradation temperature of the PUF based on TGA results. A low kinetic rate provided PUF with a high density, small cell size and a broad cell size distribution. The biodegradation of PUF containing only HTWT was 31.2% and 51.3% at 28 days and 60 days of testing respectively whereas the PUF containing 1/0.5 HTWT/PCL diols (by mole) showed a higher biodegradation: 39.1% and 64.3% at 28 days and 60 days of testing respectively. The foam formation rate of HTWT based PUF was higher than the one of HTNR based PUF. All HTWT based PUF have a higher density than HTNR based PUF. The HTWT based PUF had an inferior cell size in comparison to HTNR based PUF. The cellular structure of HTNR based and HTWT based PUF were different, but all PUFs showed almost closed cells. The HTWT based PUF had a higher thermal degradation temperature and biodegradation properties than foams from HTNR
วัตถุประสงค์ของงานวิจัยนี้ เพื่อทำการเตรียมโฟมพอลิยูรีเทนชีวภาพ (PUF) จากยางธรรมชาติดัดแปรที่มีหมู่ปลายไฮดรอกซิล (HTNR) ยางคลัมบ์ดัดแปรที่มีหมู่ปลาย ไฮดรอกซิล (HTWT) และพอลิคาโปรแลคโทน (PCL) ศึกษาผลของชนิดพอลิออล และสัดส่วนโดยโมลระหว่าง HTNR/PCL และ HTWT/PCL ที่สัดส่วน 1/0, 1/0.5, 1/1 และ 0.5/1 โดยโมล นํ้าหนักโมเลกุลของ HTNR, HTWT และ PCL ที่ใช้สำหรับงานวิจัยนี้ คำนวณจาก 1H-NMR คือ 1,800, 1,400 และ 2,000 g/mol ตามลำดับ ลักษณะโครงสร้างทางเคมีของ HTNR, HTWT และPUF สามารถวิเคราะห์และยืนยันด้วยเทคนิค FTIR และ 1H-NMR รวมถึงทำการวัดอัตราการก่อโฟม (Foam formation rate) ทดสอบสมบัติทางกายภาพ ทางเคมี และสมบัติการย่อยสลายทางชีวภาพ พบว่าในกรณีของโฟมพอลิยูรีเทนจาก HTNR/PCL เมื่อใช้ PCL ในปริมาณที่มากขึ้นจะส่งผลให้อัตราการก่อโฟมเร็วขึ้น และขนาดของเซลโฟมมีขนาดใหญ่ขึ้นด้วย ในขณะที่ค่าความหนาแน่น และความต้านทานต่อแรงดึงจำเพาะมีการเปลี่ยนแปลงเล็กน้อย การเติม PCL ในส่วนผสมของโฟมยังส่งผลให้ความสามารถในการยืด ณ จุดขาด และความทนทานต่อการกดมีค่าลดลง การคืนตัวหลังการกดของโฟม PUF2 (สัดส่วนระหว่าง HTNR/PCL = 1/0.5) จะให้ค่าตํ่าที่สุดคือ 40% ลักษณะของโฟมที่ได้จากการทดลองนี้โดยส่วนใหญ่จะเป็นแบบเซลปิด ความสามารถในการย่อยสลายทางชีวภาพของโฟม ทดสอบโดยใช้วิธี Sturm Test มี LDPE เป็นตัวเปรียบเทียบเชิงลบ และใช้ Sodium benzoate เป็นตัวเปรียบเทียบเชิงบวก พบว่าโฟมเริ่มมีการย่อยสายเกิดขึ้นอย่างเห็นได้ชัดที่เวลา 33 วัน มีเปอร์เซ็นต์การย่อยสลายในช่วง 7-11 เปอร์เซ็นต์ เปอร์เซ็นต์การย่อยสลายของโฟมจาก HTNR (PUF1) อยู่ที่ระดับ 8.4 และ 31.89 เปอร์เซ็นต์ และเปอร์เซ็นต์การย่อยสลายของโฟมจาก HTNR/PCL (1/0.5) อยู่ที่ระดับ 11.31 และ 45.6 เปอร์เซ็นต์ ที่เวลาในการทดสอบ 28 และ 60 วัน ตามลำดับ กรณีของโฟมพอลิยูรีเทนจาก HTWT/PCL เมื่อใช้ PCL ในปริมาณที่มากขึ้นจะส่งผลให้ค่าความหนาแน่นสูงขึ้น ขนาดของเซลโฟมลดลงมีการกระจายของเซลในวงกว้างไม่สมํ่าเสมอ เปอร์เซ็นต์การย่อยสลายทางชีวภาพของโฟมจาก HTWT (PUF5) อยู่ที่ระดับ 31.2 และ 51.3 เปอร์เซ็นต์ และเปอร์เซ็นต์การย่อยสลายของโฟมจาก HTWT/PCL (1/0.5) อยู่ที่ระดับ 39.1 และ 64.3 เปอร์เซ็นต์ ที่เวลาในการทดสอบ 28 และ 60 วัน ตามลำดับ เมื่อทำการเปรียบเทียบโฟมที่ได้จากการเตรียมโดยใช้พอลิออลหลักเป็น HTNR และ HTWT พบว่าโฟมจากพอลิออลหลัก HTWT ให้อัตราการก่อตัวของโฟมเร็วกว่า ขนาดของเซลโฟมเล็กกว่า ความหนาแน่น ความต้านทานต่อความร้อน และเปอร์เซ็นต์การย่อยสลายทางชีวภาพสูงกว่า เมื่อเทียบกับโฟมจากพอลิออลหลัก HTNR
Lachhab, Abdelmonem. "Caractérisation du comportement thermomécanique d'un polyuréthane compact et sous forme de mousse : application aux butées élastiques pour véhicules automobiles." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S134.
Повний текст джерелаThis PhD thesis deals with the full mechanical and thermomechanical characterization of thermoplastic polyurethane, in its compact and foam states, dedicated to antivibratory systems for automotive. This characterization has been carried out by using quantitative imaging techniques, especially infrared thermography. From a mechanical point of view, the dependency of the different phenomena involved in the material deformation - Mullins effect, mechanical hysteresis, residual deformation and volume change - on the initial density and loading rate has been established. The thermal and calorimetric signature of these phenomena has been characterized and the mechanical dissipation was estimated from energy balances. The results obtained provide an experimental database for the identification of constitutive parameters and the enrichment of behavior laws
Abdessalam, Hichem. "Modélisation thermo-rhéo-cinétique, simulation numérique et caractérisation expérimentale du procédé de moussage du polyuréthane." Thesis, Reims, 2015. http://www.theses.fr/2015REIMS004.
Повний текст джерелаWith the increasing use of polyurethane foam in the automotive industry and the complexity of the shapes of the parts, several production defects that affect the quality of the final products may occur. The use of numerical simulation tools is a valuable method to control the mold filling during the foaming process and to detect defects at an early stage. In this context, this work aimed to model and to simulate the polyurethane foaming process. Models taking into account the two main chemical reactions of the formation of polyurethane, the exothermic effect of these reactions as well as the thermo-rheo-kinetic coupling characterizing this process have been proposed. These models have beenimplemented in the software NOGRID-points based on a meshless method (FPM) which gives more flexibility in terms of simulation of free surface flows. The parameters of the used models were identified by an inverse analysis method which minimizes the difference between the numerical and the experimental results obtained by an experimental characterization work. The numerical resultswere validated by carrying out a set of short shot foams using a panel mold cavity and an automotive underlay carpet cavity. The validation was to compare the flow front positions obtained experimentally with the numerical ones. We have also proposed a prediction of some acoustic foam characteristics based on the results of the numerical simulation of the foaming process and a semiphenomenological model
Primel, Antoine. "Étude du comportement d'un mélange de fluide supercritique et de polyuréthane thermoplastique pour une application de pièces automobiles." Thesis, Lorient, 2015. http://www.theses.fr/2015LORIS378.
Повний текст джерелаThe aim of this thesis is to study the behavior of a supercritical fluid (nitrogen or carbon dioxide) and thermoplastic polyurethanemeltmix during the production of jounce bumpers by the MuCell® injection molding process. First of all, the state of the art was developed in a literature review which allowed to describe the main phenomena that occur during processing of a mixture of supercritical fluid and polymer in microcellular foam. Then, a study at the laboratory scale allowed to characterize and model the behavior of a thermoplastic polyurethane in contact with a supercritical fluid and deduct the characteristics and behaviors essential to the understanding of various phenomena encountered during the process(diffusion, solubility , nucleation...). Finally, the last part of this work concerns the implementation of previously acquired knowledge on industrial means in order to analyze and stabilize the generated microcellular foam
Cerdan, Florent. "Etude du vieillissement hydrique et des effets de couplages hygro-thermo-mécaniques sur le comportement d'une mousse polyuréthane renforcée par des fibres de verre au sein d'une membrane Mark III." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2017. http://www.theses.fr/2017ESMA0028/document.
Повний текст джерелаThe insulation of containment membrane of liquid natural gas carrier using the MarkIII membrane system, consists of load-bearing system made of panels in glass fiber reinforced polyurethane foam. The membrane is designed to resist to mechanical and thermal service load cases. As stated by IGC code regulation, and more specifically in some critical safety scenario, it has to be demonstrated that the cargo containment system will keep its integrity and main functions when subjected to water leakage through the inner hull wall (ballast).The challenge of this study is to appreciate the behavior of the reinforced polyurethane foam in immersion, which could widen the understanding of both water diffusion mechanisms and the impact of water penetration on the properties of the material.The setting up of water sorption tests at ambient temperature, according to three conditioning "free", "blocked" and "coupled" has allowed to identify a swelling law, a loading law and a damage law.In "free" conditioning, the cellular structure and the orientation of glass fibers in XY planes induce an anisotropic hygro-mechanical coupling. The swelling of Z direction has an important impact on the water solubility levels.In "blocked" conditioning, the blocking of the displacement of the faces perpendicular to the Z direction induces an increase in the internal stress levels as a function of the progression of the penetration front. In "coupled" conditioning, the sequence of the water aging and the cryogenic aging causes several damages. The damage degree is proportional to the hygroscopic swelling level of the cellular structure.The impact of these different conditionings on the durability of the material mechanical properties has been evaluated
Larochette, Mathieu. "Mousses de polymères : étude des procédés de synthèse et de mise en forme." Pau, 2007. http://www.theses.fr/2007PAUU3016.
Повний текст джерелаPolymer foams are used for many applications thanks to their properties: lightness, insulation, impact resistance. . . In this work, we studied the elaboration of two kind of materials: polyurethane foam and extruded polystyrene foam. In the case of polyurethane, the correlation between the kinetic of polymerization and the foaming is important. For the polystyrene, we shown that the residence time distribution theory modelize properly the extrusion process. We found a relationship between the structural anisotropy and the thermal anisotropy coupling an experimental and a numerical approaches. The morphological anisotropy observed on industrial foam does not permit to observe the anisotropy of temperature field
Cuve, Léon. "Synthèse et caractérisation de polyuréthannes à séquences polybutadiène hydrogéné." Lyon, INSA, 1990. http://www.theses.fr/1990ISAL0019.
Повний текст джерелаSaetung, Anuwat. "Preparation of polyurethane foams from hydroxytelechelic oligoisoprenes obtained by controlled degradation of natural rubber : study of their physico-mechanical, thermal, and acoustic properties." Le Mans, 2009. http://cyberdoc.univ-lemans.fr/theses/2009/2009LEMA1006.pdf.
Повний текст джерелаPolyurethane foam (PUF) is the largest of polyurethane materials widely studied and used in many applications such as furniture, automobile, insulation, acoustic absorber. Hydroxyl compounds currently used in the production of PUF are petrochemical products (polyester and polyether polyols). However, they have some disadvantages as they are non-renewable resources, they may cause environmental pollution, and they tend to be exhausted in the near future. Natural rubber (NR) is an interesting choice to use as a starting material in PUF synthesis, due to the fact that they are renewable source, abundant polymer and they have good mechanical properties and are easy to chemically modify. In this work, a new hydroxytelechelic natural rubber (HTNR) having a hydroxyl functionality of 2 was successfully performed via controlled epoxidation and cleavage of natural rubber, following by a selective reduction reaction of the obtained carbonyltelechelic oligoisoprenes. These HTNR with different molecula r weights (1000-3400 g mol-1) were reproducible obtained with high yields. Chemical modifications on HTNR were performed by epoxidation (10-35%, EHTNR), hydrogenation and oxirane opening reactions. The different microstructures of these oligomers were evidenced by the characterization techniques FT-IR, NMR, SEC and MALDI-TOF MS. Their thermal properties were also investigated by TGA and DSC. Polyurethane foams were successfully prepared from a renewable source, HTNR with different molecular weights and EHTNR having a variation of epoxide content, by one shot technique. The chemical structure and cell structure as well as physico-mechanical, thermal and acoustic properties were characterized to compare with commercial polyol analogues. It was investigated that the obtained HTNR based foams are open cell structures and have cell dimensions between 0. 38 and 0. 47 mm. Concerning, physico-mechanical properties, HTNR1000 based foam exhibits higher tensile and compressive strengths than commercial polyol analogue, but the elongation at break is lower. However, HTNR3400 based foam shows the best for elastic properties. In series of EHTNR based foams, the tensile and compressive strengths give a trendy increasing with increasing the epoxide content. Same results were observed with increasing amount of 1,4-butanediol. For thermal properties, HTNR based foams show better low temperature flexibility than that based on commercial polyol. Moreover, HTNR based polyurethane foams give an excellent acoustic absorber
Jmal, Hamdi. "Identification du comportement quasi-statique et dynamique de la mousse de polyuérathane au travers de modèles de mémoire." Phd thesis, Université de Haute Alsace - Mulhouse, 2012. http://tel.archives-ouvertes.fr/tel-01017088.
Повний текст джерелаHubert, Franck. "Valorisation chimique de déchets polyéthylènetéréphtalate en matériaux polyuréthane pour l'isolation thermique." Châtenay-Malabry, Ecole centrale de Paris, 1996. http://www.theses.fr/1996ECAP0482.
Повний текст джерелаTestouri, Aouatef. "Highly structured polymer foams from liquid foam templates using millifluidic lab-on-a-chip techniques." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00771862.
Повний текст джерелаGalland, Geneviève. "Perméabilité et diffusion des gaz à travers les membranes de polyurethanne : relations propriétés-structure." Lyon, INSA, 1985. http://www.theses.fr/1985ISAL0017.
Повний текст джерелаCornille, Adrien. "Substitution des Isocyanates dans les Polyuréthanes pour l’Elaboration de Matériaux Adhésifs et Expansés." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2016. http://www.theses.fr/2016ENCM0010/document.
Повний текст джерелаPolyurethane ranks as the sixth most produced polymer in the world. Nevertheless, these materials are obtained from harmful monomers: isocyanates. Isocyanates are toxic and sometimes CMR (Carcinogenic, Mutagenic, Reprotoxic) and represent a danger for the environment, the formulator and the final user. To protect their employees and consumers and in the context of the REACH regulation , Bostik and Arkema, the two companies of the consortium CYRRENAS funded by the Agence Nationale de la Recherche, target the substitution of isocyanates in polyurethanes and thus the production of Non-Isocyanates Polyurethane (NIPU) materials. Among the different access routes to NIPUs, the innovative cyclic carbonate/amine way was considered in order to synthesize polyhydroxyurethane (PHU) materials. A detailed study by spectrometric (NMR) and thermic (DSC) analyses on model reactions between mono-cyclic carbonates and mono-amines allowed to bring to light the parameters influencing the reactivity as well as the limitations of this technology. This manuscript also focuses on the elaboration of flexible and rigid PHU materials, on their thermal, mechanical, thermomechanical and adhesive properties on different substrates. The polyurethane is also very largely employed in flexible and rigid foams which represent 2/3 of the worldwide market. In this context, the first PHU foams were synthesized and thermally and mechanically characterized. Finally, with the objective to circumvent the limitations of the PHU synthesis, a new approach for the formulation of polyurethanes without isocyanates was developed from aminotelechelic prepolymers containing hydroxyurethane moieties and biobased epoxidized compounds used as chain extenders. The materials resulting from this formulation are called H-NIPUs
Coelho, Da Silva Mercês. "Contribution à l'étude des composites à base de fibres de cellulose." Grenoble INPG, 2008. http://www.theses.fr/2008INPG0143.
Повний текст джерелаThis dissertation is a contribution of scientific knowledge on the characteristics of several by-products from a bleached eucalyptus kraft pulp mill and their possible valorisation as fibrous raw materials. The structural, thermal, and morphological investigations of these raw materials were carried out and the results obtained indicate that these industrial wastes can be used as potential raw materials in fiber-based applications. The introduction of the fibres into RPU did not alter their thermal stability, but enhanced their density. The use of cellulose fibres as reinforcing phase increased the resistance to compression of the resulting foam, enhanced their thermal insulation performances and their biodegradation rate
Duquesne, Sophie. "Etude des procédés d'ignifugation de substrats polymères par revêtements intumescents : application aux polyuréthanes." Lille 1, 2001. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2001/50376-2001-Duquesne.pdf.
Повний текст джерелаConcernant le système PU/EG, une faible modification du processus de carbonisation naturelle du PU est observée. La caractérisation du processus de carbonisation, menée selon une approche physique met en évidence une aptitude à la déformation de la structure carbonée formée par dégradation du revêtement PU/APP. Aucours d'un incendie, cette structure va donc se déformer plutôt que de se fissurer et ainsi permettre un maintien des performances RF. Dans le cas du système PU/EG, l'épaisseur importante, la faible densité et, comme il est possible de le supposer la faible conductivité thermique du bouclier intumescent permettent de comprendre le mode d'action de l'EG
Denay, Anne-Gaëlle. "Mécanismes et tenue mécanique long-terme de mousses polyuréthanes pures et renforcées aux températures cryogéniques." Phd thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2012. http://tel.archives-ouvertes.fr/tel-00740110.
Повний текст джерелаPradel, Pierre. "Etude de la compaction dynamique de mousses polymères : Expériences et modélisation." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2017. http://www.theses.fr/2017ESMA0035/document.
Повний текст джерелаPolymeric foams are widely used in many industrial applications as thermal insulators, structural materials or shock mitigators. Indeed, they are light weight materials with an excellent weight /stiffness ratio and low production costs. One of the applications which interests the CEA is the protection of structures against mechanical loadings generated by laser irradiation or high velocity impact of small debris.The main objective of this PhD thesis is to investigate the mitigation capability of an expanded polyurethane foam and an epoxy syntactic foam against extremely fast (> 106 s−1) and intense(> 10 GPa) dynamic loadings. Cyclic quasi-static tests and dynamic experiments have been performed to investigate the behavior of these two foams for strain rates ranging from 10−3 to 106 s−1. Analysis of the experimental results shows that these polymeric foams have an elastic behavior phase followed by a compaction phase with significant permanent sets. Compaction thresholds are about 9 MPa for the polyurethane foam and 30 MPa for the epoxy foam under quasi-static loadings and around 21 MPa for the polyurethane foam and 72 MPa for the epoxy foam for strain rates above 104 s−1.Two porous compaction models are developed to represent the macroscopic behavior of these foams for such strain rates. The parameters are identified from the results of dynamic compression experiments (gas gun, low inductance generator). The validity of the models is tested by comparing calculated velocity profiles with an explicit hydrocode and velocity profiles measured during the experiments. These models are then used to analyze the results obtained with electron beam irradiation and laser-driven shock experiments. We demonstrate that the studied polymeric foam shave high mitigation capabilities and that the models are valid for high strain rates
Haji, Esmaili Shabnam. "Application des mousses alvéolaires en photocatalyse : étude de la dégradation du méthanol." Strasbourg, 2011. http://www.theses.fr/2011STRA6092.
Повний текст джерелаIn recent decades, the gradual reduction of water and air quality has become a serious danger for all living species, among them human beings. Awareness of this environmental problem has led to a strong growth in the field of environmental scientific research and commercials equipment in order to develop new, efficient and not too expensive processes to improve the quality of water and air. Advanced oxidation process (AOP), particularly photocatalysis based on the utilization of titanium dioxide (TiO2), is considered as an advanced air and water purification technique in comparison with the other classical techniques. The first objective of this study is to compare two different configuration photocatalytic reactors for methanol degradation; seep-flow mode reactor, and traversed-flow mode reactor filled with 3D alveolar foams as a support of photocatalyst. The principal objective is to choose and characterize the most appropriate alveolar foam to obtain a maximum rate of methanol degradation. To achieve this goal, three new alveolar foams were chosen to be studied; polyurethane foam, carbon foam and beta silicon carbide foam. First of all the three foams were characterized, particularly focusing on the measurement of the pressure drop and light transmission through the foams. In the second step their functions on the surface, especially oxygen functions, were studied by XPS spectroscopy. Additionally, their surface morphology was observed by scanning electronic microscopy and transmission electron microscopy. Finally the specific surface of every foam sample was measured by BET method. The challenge was to optimize the method of photocatalyst deposition on the three alveolar foams and to assure that this process doesn’t cause any decrease in the transmission of light. After this optimization, the seep-flow mode reactor and traversed-flow mode reactor (filled with 3 dimensional alveolar foams covered with photocatalyst), were used for the degradation of Methanol vapor. The essential role of the type of the reactor and the nature of the foam, in the case of traversed-flow mode reactor, were observed with several experiments of methanol degradation. [. . . ]
Youssef, Souhail. "Etude par tomographie X et modélisation par éléments finis du comportement mécanique des mousses solides." Lyon, INSA, 2004. http://theses.insa-lyon.fr/publication/2004ISAL0079/these.pdf.
Повний текст джерелаThe mechanical properties of cellular materials are related to their micro-structure. In fact, macroscopic stresses are the consequence of stresses in the cell wall and struts and of stresses in the cell walls and struts and of the cell failure mechanisms. In the present work we perform tomography during in situ compression tests on different type of foams to inspect the 3D-microstructure and deformation mechanisms. We also present a method to transform large data images of actual microstructures into a tetrahedral mesh, which will be used to model the mechanical behaviour by the finite element method. We finally confront computation results and in situ observations to validate the model. X-ray Computed Micro Tomography (XRCMT) has been widely used recently as a non-destructive technique that gives picture of the interior of cellular solids. This allows studying architectural parameters and, when coupled with in situ loading tests, deformation mechanisms of foams. Local deformation mechanisms of closed cell foam have been studied during compression experimentally by X-Ray tomography and numerically by FEM. The presence of elastic buckling and plastic yielding of foam walls was observed. The combination of effective e modelling tools gives attractive opportunities to build sufficiently large data model to represent the foam structure. Once the modelling technique was validated, we use it to study the effect of various bulk material properties for a same microstructure of the foam on the mechanical behaviour. The mechanical response of these foams was also studied numerically under various uniaxial loads configuration and multiaxial loading
Mouquet, Aymeric. "Structure et élasticité des films moussés : Effets de la distribution des tailles des bulles." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1108/document.
Повний текст джерелаThe subject of this experimental work is the study of foam films mechanics with a confined structure because of their low thickness. With our foaming method using polyurethane particles dispersion, we generated foam films with independent control over the gas fraction (or the density), the thickness e or the pore size distribution (with a mean diameter D ̅_b). For this last parameter, we focused on monodisperse, bidisperse and polydisperse distributions. Obtained structures were studied using X-ray tomography to quantify confinement-induced order (density profiles, pore center spatial position, structural elements size,…). The mechanics of such foam films was studied in both uniaxial tension (in-plane) and compression (orthogonal plan). A particular work was done on the polymer matrix in order to determine reduced values (moduli and characteristic stress) to compare our results with models in the literature. We show that in addition to the classic density effect, the mean number of bubbles across the thickness, i.e. e⁄D ̅_b is a determinant parameter for both stress directions. In tension, parietal walls contribute to increase the elastic modulus of films with respect to non-confined foam. This effect on the mechanical strength is even more important (up to two times) when e⁄D ̅_b is small without any effect regarding the pore size distribution. In compression, parietal walls do not contribute directly to the measured values but the confinement still has an important role, this time depending on the pore size distribution. Indeed, monodisperse foam films are organized in polycrystals with much better mechanical characteristics compared to polydisperse foam films that present numerous mechanical weak spots caused by initial bubble packing defects. Bidisperse foam films mechanical behavior is either close to monodisperse or polydisperse foam films respectively for high or small e⁄D ̅_b ratio
Ould, Eyih Aghdhefna. "Contribution à l'étude du comportement en grandes déformations des mousses : Modèle de simulation numérique de chargement d'un siège par un mannequin." Ecully, Ecole centrale de Lyon, 1993. http://bibli.ec-lyon.fr/exl-doc/TH_T1536_aouldeyih.pdf.
Повний текст джерелаThe study of the passenger's comfort requires the modelisation of the seat. It's structure is very complex and is made of different materials and elements: springs, cables, beams, polyurethane foam,. . . The foam behaviour modelisation is required to build a global model of the seat: this problem comes down to identify a deformation energy density function, W. Three approaches are examined to give an analytical expression of the W function: Micromecanic: from microstrucrual hypothesis of material, on the elasticity of its constituents and from a statistical law governing the repartition of the molecules, we search a physical explanation of the observed phenomenon. /Minimecanic: the starting point is the notion of representative volume. It allows us to express the parameters of the W function from the basic element characteristics: cell, morphology, density and mechanical properties of the material. /Macromecanic: we try to identify a given form - a priori - of the function, from a certain number of homogeneous deformations without taking into account a physical explanation of the parameters. A complete study of the hyperelastic materials allowed us to identify the polyurethane foam as a purely compressible HILL material. We find good agreement between the numerical results of the global and the experimental tests of the H point made with 95% mannequin. The contribution of the gas in the dynamical stiffness of the foam was analysed. A linear model with 1 d. O. F. Is built to study the dynamical behaviour, around an equilibrium position, of a foam sample
Santiago-Medina, Francisco José. "Tanins condensés pour mousses rigides et nouvelles réactions de réticulations des matériaux polyphénoliques." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0248/document.
Повний текст джерелаAn alternative to industrial phenol or resorcinol industrial products may be tannins or lignin. Both are natural polyphenols, the tannin is extracted from different parts of plants, while lignin is usually obtained as a secondary product in the pulp and paper mill. These two products are the main basis on which I have worked during the development of this thesis. In a first part, a study of characterization and differentiation between different tannins with the same origin and that present a different behavior when used in the same application under the same conditions has been done. Highlighting the GPC as a fundamental technique for the differentiation between sulphited quebracho tannins. On the other hand, the interactions between different substances with tannin and with lignin have been studied. As the study of the reaction between diamines (such as hexamethylenediamine) with tannin and lignin to obtain a polycondensed resins. Also, in this section have been obtained polyurethanes with at least 70% of natural substances in their preparation without using any isocyanate in the process. In addition, aldehydes derived from lignin, such as vanillin, have been used next to pine tannin for the manufacture of adhesives in the preparation of particleboards, obtaining satisfactory results according to European standards and from completely natural substances. Finally, within an industrial project the initial steps have been carried out for the development of a rigid tannin foam applicable by projection for the thermal insulation of buildings. Where a new mechanical foaming system has been developed for tannin foams based in fire-fighting foams or in the foams of the tunneling operations, this new system of foaming avoids the problems of shrinkage during the formation of the foam
Belkadi, Salima. "Mesure des déplacements et déformations en trois dimensions par stéréoscopie : applications au comportement de mousses synthétiques." Poitiers, 2002. http://www.theses.fr/2002POIT2256.
Повний текст джерелаThe aim of this work is the study of the behaviour in compression of the synthetic foam of polyurethane (PU), polyethylene (PE) and polypropylene (PP), we have used the stereoscopic principle associated with two optical methods; the techniques of correlation and the technique of tracking-marks. They permit the 3D reconstruction of specimen surface at the interested points then the determination of 3D displacements and deformations during solicitation. The stereoscopic dispositif requires a calibration to determine its intrinsic parameters (lens, pixel size, distortion coef) and extrinsic parameters (orientation and position of CCD cameras). We have studied two configuration of stereoscopic system; parallel case and classic case (crossed optical axes). For the compression tests, we have used the technique of tracking-marks, which is simple to realise. This permitted us to identify the behaviour law of HILL used for the simulation of compression with finite elements code ABAQUS - IMPLICITE
Deschanel, Stéphanie. "Dynamique des précurseurs de la rupture des matériaux hétérogènes : application aux mousses polymères vitreuses." Lyon, INSA, 2005. http://theses.insa-lyon.fr/publication/2005ISAL0093/these.pdf.
Повний текст джерелаIn order to predict failure time of materials, a new approach has been considered : fracture can be viewed as a critical phenomenon. For some materials fracture can be seen as a clustering of microcrackes. We focus on heterogeneous materials (vitreous polymer foams) whose fracture can be described as a phase transition. Our main experimental tool is the monitoring of the acoustic emission signatures of the microfractures, which occur during mechanical tests. We highlighted diffuse microcrack nucleation and progressive localization into a dominating crack with a good fit of the energy by a power law. The exponet of this power law does not seem to depend neither on the material density, the loading mode, nor the behavior law. The time intervals between two damaging evants seem to be power law distributed only if the stress remains nearly constant for the most part of the test. A critical region where the cumulative energy could be described by a power law appears only for creep tests
Gropplero, di Troppenburg Giacomo. "Dispositifs microfluidiques dans les mousses polymères : fabrication, modélisation et applications biologiques." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI060.
Повний текст джерелаMicrofluidics and an appropriate substrate are essentials for the design of low-cost point-of-care diagnostic devices. The particular mechanical and structural properties (porosity, elasticitydots) of polymeric foam are unique among the other widespread materials in microfluidics (PDMS, paper, plastic materials, glass, silicondots). A systematic screening of the different capabilities provided by polymeric foam as a new substrate for microfluidics is offered in this thesis. First off, a shaping process is proposed for the production of fluidic microsystems. This new process relies on the combined usage of a polymeric foam and an elastomer to produce highly elastic fluidic systems that keep the initial structural properties of the foam. Based on a controlled and repeatable embossing technic, the process is compatible with industrial production. A coupled numerical model also allows its optimization. The resulting foam microfluidic devices have, besides capillarity, a decisive asset : the option of a manual compression or an external peristaltic actuation for a contamination-free control of the microfluidic flows. The peristaltic actuation can function as a pump and as a valve. A lumped elements model enables a dynamic reproduction of the fluidic behavior inside the foam channels. To ensure proper integration in low-cost portable devices, the fundamental stages of a diagnostic test (retrieval and preparation of a sample, detection) are validated. We show that filtration of objects of only a few tens of micrometers in size is possible. The foam devices can also be chemically functionalized to optimise the capture of specific biological targets. The fluorescent or colorimetric detection of biological elements is equally possible by means of isothermal DNA amplification. Finally, a blood typing prototype gives access to the blood group of a whole blood sample in a few minutes. This last test is carried on an integrated device which highlights the main benefits of a foam device : robustness, user-friendly, embedded reagents, multiple materials combination, transport of a biological sample by external compression controlled by an operator, direct readout of a result in a few minutes
Morvan, Myriame. "Caractérisation des odeurs de matériaux de l'habitacle automobile par "nez électronique", analyse sensorielle et analyse physico-chimique." Toulouse, INPT, 2001. http://www.theses.fr/2001INPT026G.
Повний текст джерелаArbenz, Alice. "Synthesis and caracterization of new bio-based macromolecular architectures based on tannins and microalgae derivatives for construction field applications." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAE002.
Повний текст джерелаIn a context of sustainable development, new biobased and aromatic macromolecular architectures were synthesized from two types of renewable resources: tannins, extracted from wood, and glycerides derived from plant or from microalgae to develop innovative materials for building applications. Firstly, the alkoxylation reaction was performed on tannins. Polyether glycol (propylene or butylene) chains were grafted on tannins extracted from different botanical sources species, resulting in various macropolyols with various controlled macromolecular architectures. Based on these macropolyols, polyurethanes were synthesized by varying the reaction parameters to control the final properties of materials to fit specific requirements. PU proofing membranes and rigid urethane-isocyanurate foams for insulation were elaborated. Finally, algal oil and rapeseed oil (as reference) were modified in epoxides and polyols. These new building blocks were incorporated in the structure of urethane-isocyanurates foams to study the impact of the type and the number of reactive functions on the final properties of rigid foams.New renewable bio-based building blocks were developed and integrated in the final macromolecular architectures and materials. The great potential of tannins and glycerides from microalgae for developing high-performance materials, for building applications, especially waterproofing membranes and insulation foams has been clearly established
Bustamante, Valencia Lucas. "Etude expérimentale et numérique de la décomposition thermique des matériaux à trois échelles : Application à une mousse polyéther polyuréthane utilisée dans les meubles rembourrés." Phd thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aéronautique, 2009. http://tel.archives-ouvertes.fr/tel-00444898.
Повний текст джерелаDenninger, Marc. "Conception d'un matelas passif sur mesure." Thèse, Université de Sherbrooke, 2008. http://savoirs.usherbrooke.ca/handle/11143/1836.
Повний текст джерелаBaron, Samuel. "Polymère souple pour antenne patch électriquement accordable en bande X : conception et caractérisations." Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=cd5ee96a-50ba-475f-b933-7edc17cf7cc3.
Повний текст джерелаIn communication systems, smart antennas with large frequency tunability (agility) have been gaining worldwide attention over the past few years due to the proliferation of global wireless communication standards in close proximity to one another. However, conventional solutions use electronic components which induce additional costs and make the system more complicated. Moreover, the electronic devices have moved from rigid to flexible dielectric substrates to reduce the cost and to obtain stretchability and conformability properties. The goal of this thesis is to put together these two topics. The chosen original approach consists of the mechanical reconfiguration of antenna patch printed on a soft membrane substrate with electrostatic actuation in X band, at around 10 GHz. Moreover, a new polymeric substrate was employed in this structure, the polyurethane (PU). Firstly, the technological processes required to realize the antenna patch on the PU substrate were developed. Then, the dielectric properties of polyurethane films were measured on a large frequency band in order to define the antenna patch dimensions using high frequency simulations. Finally, the first antennas patch realized and characterized have a figure of merit Frequency tunability/Voltage higher than the state of the art. Preliminary studies were also carried out to explore various feasible ways for improved the antenna systems performances
Ezbakhe, Hassan. "Caractéristiques thermiques et mécaniques de matériaux poreux utilisés comme isolants simples ou porteurs." Lyon 1, 1986. http://www.theses.fr/1986LYO10024.
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