Dissertations / Theses: 'Polyester resin'

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Tshulu, Rene N. "Aspects of segregation phenomena in polyester resin blends." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/849063/.

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The concept of phase separation offers one route of applying a primer and top-coat in a single coat. In such systems, two incompatible resin materials are blended in a common solvent, which then phase separates as two coating layers upon solvent evaporation. The goal of this thesis is to provide an insight into the phase separation phenomena based on two commercial, incompatible, resins Dynapol and Synoalc which are both polyesters. To accomplish this, two complementary areas of study were undertaken: surface analysis of the constituents that compose the system and interfacial analysis of the phase-separated coating. In this study, X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) have been utilised. Ultra-low-angle microtomy (ULAM) has been used for the exposure of the buried interfacial layers. Principal component analysis (PCA) and non-negative matrix factorization (NMF), were used for the development of data analysis pre-processing procedures for interpreting the ToF-SIMS spectra and imaging datasets. Due to the complex nature of the commercial resins, containing similar monomer constituents, six model polyesters were synthesised specifically for the structural characterisation of the commercial systems. The model resins were synthesised under a systematic manner i.e. by precisely designing their chemical structure in relation to the monomer composition of the commercial systems. These spectra permitted the determination of the molecular composition of Dynapol and Synoalc accurately. The use of PCA in combination with the model resins permitted the discrimination of Dynapol and Synoalc on the basis of glycol monomer, with the identification of key diagnostic ions necessary for ToF-SIMS imaging. Using ToF-SIMS-NMF image analysis, the identification, differentiation and visualisation of the phase separated constituents throughout the bulk was achieved. The parameters influencing the phase segregation process were identified and the dominant driving forces of layer formation were attributed to: i) minimisation of the surface energy of the whole system, ii) the influence of polarity difference between the phase separating layers and iii) the presence of pigmentation that supports and inhibits the mobility of the phase separated resin layers in favour of layer formation.

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Tully, Patricia Haverty. "Dielectric and Kinetic Analysis of Thermosetting Polyester Resin." W&M ScholarWorks, 1989. https://scholarworks.wm.edu/etd/1539625521.

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Yang, Huan. "Integrated analysis of unsaturated polyester and Vinylester Resins in vacuum-assisted resin transfer molding (SCRIMP) /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488205318511314.

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Hider, Jennifer Agnes. "Analysis of a thermosetting polyester resin with novel crosslinking agent." Thesis, Kingston University, 2003. http://eprints.kingston.ac.uk/20711/.

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A novel crosslinking agent, 2,4-diallyloxy-6-diethylaminotriazine, was used for the cure of unsaturated polyester resins based on maleic anhydride. The aim of this investigation was to analyse the chemical structure of these cured resins. The analysis of thermosets is difficult because once cured the resin is both insoluble and infusible. An analytical strategy was devised to overcome these difficulties by using several different approaches. Spectroscopy formed an important part of this investigation. Both NMR and FT-IR were used to characterise the precursor materials and FT-IR spectroscopy for the final products. This technique was also used to monitor the curing reaction in conjunction with DSC studies. These studies showed that other chemical changes were taking place as well as the expected loss of the carbon double bonds. The extent of cure of these resins is usually determined by a solvent extraction method and this was followed by C,H,N analysis of both the soluble and insoluble (gel) fraction. An HPLC method was developed to measure the amount of unreacted monomer in the extract. Further information on the cured structure could only be obtained by destructive methods and both chemical and thermal degradation methods were examined. The attempt to release the crosslinking chain from the cured polyester by alkaline hydrolysis was unsuccessful because the cyanurate links were found to be more susceptible to hydrolysis than the phthalate and maleate links. Pyrolysis of the resins gave an extremely complex mixture of products. Many of the products identified for the resins were also identified when a homopolymer of 2,4- diallyloxy-o-diethylaminotriazine was pyrolysed. These included aromatic and other ring structures. This evidence in conjunction with the spectroscopic studies suggested that the monomer did not produce linear crosslinking chains but that several monomer units were linked together to form a three-dimensional structure which acted as a crosslinking junction for the linear polyester chains and that this structure was likely to involve some fused rings. A further aim of this research was to review the methods currently available for the analysis of thermosets and make recommendations based on this study and the literature search to other analysts dealing with this class of materials. There have been major developments in spectroscopic techniques which mean that far more data can now be obtained on these systems than previously. FT-IR spectroscopy is probably the most applicable method. There are also major developments in the use of pyrolysis with GC and/or MS, but interpretation of these results with respect to the original structure requires care. Development of chemical modification methods are continuing, particularly on the small scale for identification of components by GC. In the case of structural analysis, once an appropriate method for cleaving the structure has been obtained, then spectroscopic analysis of the products can provide a great deal of information, particularly NMR spectroscopy.

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Davallo, Mehran. "Mechanical behaviour of glass-polyester composite formed by resin transfer moulding." Thesis, Manchester Metropolitan University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301045.

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Kayatin, Matthew Jay Davis Virginia A. "Rheology, structure, and stability of carbon nanotube-unstaturated polyester resin dispersions." Auburn, Ala, 2008. http://hdl.handle.net/10415/1421.

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Shohada, Mohsen-Fadaee. "Polyester resin concrete : mix development and the structural behaviour of some components." Thesis, Durham University, 1987. http://etheses.dur.ac.uk/9299/.

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Heib, Bertrand. "Développement de vernis d'isolation électrique présentant des propriétés thermomécaniques améliorées à 180°C." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENI018/document.

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Cette thèse porte sur le développement de résines polyesterimides insaturés pour des applications de type vernis d'imprégnation pour isolation électrique. Il s’agit de matériaux polymères thermodurcissables, qui assurent la double fonction d'isolant et d'agent de cohésion du système isolé. Ils se différencient en classes thermiques, qui définissent leur température maximale d'utilisation. Dans le cadre de cette étude, nous cherchons à développer des produits de classe thermique supérieure ou égale à 180°C. Une première partie de cette étude a porté sur l'amélioration de deux produits commerciaux à base de polyesters insaturés à fonctions terminales imides. Notre attention s'est portée sur la modification de leur structure chimique, afin de voir comment les différents précurseurs utilisés influencent les propriétés des résines. Une seconde partie a consisté à développer de nouvelles résines à base de polyesterimides insaturés, à partir de trois types de précurseurs imides difonctionnels
This thesis focuses on the development of unsaturated polyesterimide resins as impregnating varnishes for electrical insulation applications. These thermosetting polymer materials provide the dual function of insulating and cohesion agent of the isolated system. They differ in thermal classes, which define their maximum operating temperature. In this study, we tried to develop products with a thermal class above or equal to 180°C. The first part of this study focused on the improvement of two commercial products based on imide-endcapped unsaturated polyester. Our attention turned to the modification of their chemical structure, to see how the different precursors used affect the thermal and mechanical properties of resins. A second part was to develop new unsaturated polyesterimide resins, using three types of difunctional imide precursors

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Niknafs, Ali. "Synthesis and characterisation of a novel hydroxylated polyester resin system for coil coatings." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/6774/.

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The continuous coating of steel and galvanised steel coils is referred to as coil coating. Coil coating is considered the most efficient coating method with regard to the amount of coated area per unit of time. Coil coatings include primer coating, top coating and backside coating. In general, the primer coating and top coating need to balance effectively among flexibility, adhesion, and film hardness. As such, saturated polyester resins with the capability of being molecularly engineered have found applications in coil coatings as the key binder. Nowadays, a combination of up to five polyester resins with different molecular structures are employed in coil primer coatings and coil top coat coatings to derive hard yet flexible coatings. The aim of this study was to synthesise and characterise a novel and standalone polyester resin system that would provide multiple properties simultaneously, thus, eliminating the need to use mixtures of polyesters in coil coatings. The multiple properties concerned included high flexibility, excellent adhesion and sufficient chemical resistance. For development of the polyester resin system concerned, a variety of polyols and dicarboxylic acids were polymerised to form polymeric polyester binders. Direct esterification polymerisation technique was employed for synthesis of the polyesters. The results obtained at an early stage indicated that in order to develop such a single resin system, achievement of an optimum balance among flexibility, adhesion and glass transition temperature was essential. Differential scanning calorimetry (DSC) showed that the augmentation or reduction of the glass transition temperature of the saturated polyester led to the augmentation or reduction of the film hardness of the resulting coil coating. Thus, a unique blend of neopentyl glycol, 1,4 cyclohexanedimethanol,1,6 hexanediol, adipic acid, isophthalic acid, and terephthalic acid was polymerised. The resulting product performed efficiently as a standalone binder system in a coil primer coating and a coil top coating, providing all of the required properties. Mglecular structures of the saturated polyesters synthesised were confirmed by carbon-13 and proton CH) nuclear magnetic resonance (NMR) and Fourier transformed infrared (FTIR). Alterations made to molecular structure of the polyesters through partial replacement of their diots with new ones were visible in expected frequency ranges of the resulting 13CNMR and 1HNMR spectra. According to size exclusion chromatography (SEC), molecular weight characteristics of the pilot scale and the industrial scale reproductions of the novel, single component coil coating polyester resin system developed were comparable with the initial product synthesised at the lab scale.

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Wood, Arran R. "Investigation of interfacial properties in a composite of nanomodified polyester resin and glass fibre." Thesis, University of Surrey, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511118.

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Tsoi, Marvin S. "Modeling of thermal properties of fiber glass polyester resin composite under thermal degradation condition." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4711.

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Composites, though used in a variety of applications from chairs and office supplies to structures of U.S. Navy ships and aircrafts, are not all designed to hold up to extreme heat flux and high temperature. Fiber-reinforced polymeric composites (FRPC) have been proven to provide the much needed physical and mechanical properties under fire exposure. FRPC notable features are its combination of high specific tensile strength, low weight, along with good corrosion and fatigue resistance. However FRPC are susceptible to thermal degradation and decomposition, which yields flammable gas, and are thus highly combustible. This property restricts polymeric material usage. This study developed a numerical model that simulated the degradation rate and temperature profiles of a fiber-reinforced polyester resin composite exposed to a constant heat flux and hydrocarbon fire in a cone calorimeter. A numerical model is an essential tool because it gives the composite designer the ability to predict results in a time and cost efficient manner. The goal of this thesis is to develop a numerical model to simulate a zonal-layer polyester resin and fiber-glass mat composite and then validate the model with experimental results from a cone calorimeter. By inputting the thermal properties of the layered composite of alternating polymer and polymer-infused glass fiber mat layers, the numerical model is one step closer to representing the experimental data from the cone calorimeter test. The final results are achieved through adding a simulated heat flux from the pilot ignition of the degraded gas of the polyester resin. The results can be coupled into a mechanical model, which may be separately constructed for future study on the mechanical strength of composites under fire conditions.
ID: 030646184; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.M.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 53-54).
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Thermo-Fluids Track

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Tsavalas, John George. "Water-based crosslinkable coatings via miniemulsion polymerization of acrylic monomers in the presence of polyester resin." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/10130.

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Jesson, David Alan. "The interaction of nano-composite particles with a polyester resin and the effect on mechanical properties." Thesis, University of Surrey, 2005. http://epubs.surrey.ac.uk/808438/.

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The effect of various organically modified silica (ormosil) nano-particle additions on the mechanical properties of a polyester resin has been investigated. For materials produced on such a fine scale, surface properties are known to dominate the manner in which they behave. This thesis presents results from two complementary areas of study: surface analysis and mechanical testing. The surface properties of the nano-particles and the interactions of the nano-particles with a polyester and adsorbed water have been investigated. These analyses have led to the development of a model which shows that the small organic groups grafted to the silica surface (methyl, ethyl and vinyl) are able to pack comparatively densely at the surface, effectively forming a continuous monolayer. This layer is sufficiently thick to prevent interaction of retained silanol groups with the polyester resin. When the silica is modified with phenyl functionality, however, the larger size leads to a more dispersed organic coverage that cannot be considered as a complete monolayer. Hence this layer reduces, but will not completely prevent interaction of the matrix with retained silanols of the silica. The particles have been dispersed in a polyester resin successfully. The dispersion process is an important step in producing viable nano-composites. Mechanical testing of such nano-composites has found a significant improvement in the toughness properties of the phenyl ormosil modified polyester, compared with the unmodified resin, whilst the other modified polyesters show smaller improvements. When considered with the surface analysis investigation, it is argued that the improvement is a result of a reduction of the strength of the interface (with reference to a commercial nano-silica) between the particles and the matrix. The phenyl ormosil is more strongly bonded than the other ormosils. Whilst these other ormosils are able to contribute to toughness through a crack pinning mechanism, the phenyl ormosil absorbs energy through debonding and promotes plastic deformation in the matrix, around and between particles, mechanisms which lead to a greater toughness enhancement.

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Schuller, Anne-Sophie. "Etude du mécanisme de dispersion de charge dans une résine polyester : Synthèse de nouveaux dispersants." Thesis, Mulhouse, 2009. http://www.theses.fr/2009MULH3188.

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Afin d'optimiser les propriétés d'un composite polymère chargé, il est possible de procéder à un greffage de la charge afin de la rendre compatible avec le milieu continu dans laquelle elle est dispersée. Le sujet de recherche consiste à étudier et optimiser le mécanisme de greffage de molécules organiques à la surface de charges minérales.Développé il y a quelques années par la société GTI Process (groupe Mader), le "giral" est une formulation qui permet d'une part d'obtenir une bonne dispersion entre une charge et une matrice polymère et d'autre part d'augmenter les propriétés mécaniques du matériau composite final. Il se compose d'un silane, d'un acide méthacrylique et d'un dispersant. Toutefois, le mécanisme existant lors de l'ajout de giral dans une formulation charge/résine n'a pas été identifié. Nous nous sommes proposé de le comprendre. Après avoir identifié les interactions entre la surface de la silice et les constituants du giral, il nous a paru intéressant de faire évoluer la formulation du dispersant.Dans un premier temps, ce mécanisme a été étudié sur une charge témoin bien maîtrisée : la silice.La silice retenue a l'avantage de posséder une surface spécifique importante. Des analyses thermogravimétrique et infrarouge ont été réalisées sur différents échantillons (synthétisés à partir de silice et d'un ou plusieurs constituants du giral) afin de déterminer les espèces adsorbées ou greffées à la surface de la silice. Des analyses RMN du solide 13C et 29Si ont également été réalisées dans le but de déterminer les liaisons mises en jeu. En parallèle, des études en CGI (Chromatographie Gazeuse Inverse) ont été menées.Dans un second temps, des nouvelles structures ont été développées pour améliorer le dispersant contenu dans la formulation du Giral puis la formulation en synthétisant un seul composé qui regroupe toutes les fonctionnalités requises pour disperser la silice dans une résine polyester. De plus, ces nouvelles structures vont permettre d’augmenter les propriétés mécaniques du matériau composite final. Tous les composés synthétisés, dans ce travail, ont un squelette polymère qui est la polycaprolactone. L’architecture, la composition, la taille et la structure de ces polymères ont été optimisées suivant la charge à disperser. Nous avons ainsi synthétisé une large gamme de dispersants modèles fonctionnalisés et étudié leur comportement dans l'application. D'autre part, seules les méthodes de synthèse en masse, plus adaptées pour une production industrielle, ont été retenues. Ces polymères ont tout d'abord été synthétisés en laboratoire puis dans le milieu industriel. Une fois les polymères synthétisés, plusieurs essais ont été réalisés pour connaître leur influence au niveau des propriétés mécaniques du matériau composite final, déterminer les structures les plus adaptées pour répondre aux contraintes mécaniques, et connaître les quantités nécessaires pour obtenir les meilleurs résultats. Des mesures de viscosité et des essais mécaniques (essais de traction et de flexion 3 points) ont été réalisés. L'utilisation de ces composés développés au cours de ce travail de thèse ont permis de diminuer la viscosité d’une résine polyester chargée et ainsi de pouvoir augmenter le taux de charge. De plus, les faciès de rupture ont été observés par microscopie électronique à balayage afin d'observer la cohésion entre les charges et la matrice polymère du composite. La rupture apparaît au niveau de la charge et du polymère. L'efficacité de ces nouvelles structures dans l’application s'est avérée comparable, voire meilleure par rapport au dispersant de référence et au giral
To increase the properties of a composite based with polymer and tiller, it is possible to modify the tiller surface to make it compatible with the polymer in which it is dispersed. The aim is to study and optimize the mechanism of organic molecules grafting on mineral fillers surface. Developed several years ago by GTI Process (Mader group), the "giral" i s a formulation that allows a good dispersion between the tiller and the polymer matrix and also an increase of the final composite material mechanical properties. "Giral" is composed of a silane, a methacrylic acid and a dispersant. However, its mechanism with a mixture based on tiller and pol yester resin has not been identified, we proposed to understand it. After identifying the interaction between the surface of silica and "giral" components, it seemed interesting to modify the dispersant. In a first part, the "giral" mechanism has been studied on silica which is a well-known tiller. Silica used has a high specific surface area. Thermogravimetric and infrared analysis have been performed on different samples (synthesized from silica modified by one or more "giral"components) to determine the adsorbed or grafted species on silica surface. NMR analyses of 13C and 29 Si solid and Inverse gas chromatography studies were also conducted. In a second part, new structures have been developed to improve the dispersant in the "giral" formulation and the formulation itself by synthesizing a single compound that includes all the features required for the dispersion of silica in polyester resin. Moreover, these new structures will help to increase the mechanical properties of the final composite material. All compounds synthesized in this work, have a polymer backbone which is polycaprolactone. The architecture, composition, size and structure of these polymers were optimized according to the tiller used. We have synthesized functionalized dispersants and studied their behavior in the application. On the other hand, only syntheses by mass, more suitable for industrial production, were selected. These polymers have been first synthesized in the laboratory and then in industry. Once the polymers synthesized several tests were done to determine their influence in the final composite material mechanical properties, the most appropriate structures to mechanical stress, and the amounts required for best results. Viscosity measurements and mechanical tests were done. These new dispersants developed have reduced the viscosity of the mixture based on polyester resin and tiller, and thus can increase the tiller rate. Furthermore, the fracture surfaces were observed by scanning electron microscopy to observe cohesion between the tiller and the polymer matrix. The effectiveness of these new structures in the application are comparable or even better to the "giral" formulation

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Janeček, Pavel. "Vliv povrchových úprav skleněných vláken na mechanickou odezvu GF/polyester kompozitu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216224.

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The diploma thesis is aimed at an influence of surface modifications of fibrous reinforcements on mechanical properties at the fiber-matrix interface in fiber reinforced composites. Glass fibers were used as reinforcements and polyester resin was the matrix. The sample of composite consisted of polymer matrix in a form of cylindrical body placed on bundle of glass fibers. The design of the sample was constructed with respect to results of Finite Element Analysis (FEA). The tensile test using a materials testing machine (Zwick) was employed to evaluate adhesion at the fiber-matrix interface. Untreated glass fibers, fibers with commercial sizing, and fibers modified by deposition of plasma polymer film using Plasma-Enhanced Chemical Vapor Deposition (PECVD) at different deposition conditions were used for fabrication of composite samples. The fibers and composite samples were analyzed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM).

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Gokce, Neslihan. "Effect Of Fiber And Resin Type On The Axial And Circumferencial Tensile Strength Of Fiber Reinforced Polyester Pipe." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609930/index.pdf.

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In this study, the aim is to investigate the stiffness, longitudinal tensile strength and circumferential tensile strength of short fiber reinforced polyester composite pipes produced by centrifugal casting production method. To achieve this aim, theoretical calculation of modulus of elasticity of pipes was done and then test program was carried out on pipe samples produced with three different resin types which were orthophthalic, isophthalic and vinyl ester resin and three different fiber types which were E glass fiber, ECR glass fiber and basalt fiber. The tests were performed according to ISO (International Organization for Standardization) standards. When resin type and fiber type effect on the fiber reinforced polyester pipe samples were evaluated, calculated elastic modulus values were in accordance with the test results. According to the experimental test data, which were used to evaluate the effect of resin type on fiber reinforced polyester pipe properties, there is not a significant difference was observed in the stiffness, longitudinal and circumferential tensile strength test results of pipes having different resin types. In other words, there was not a significant effect of resin type on the stiffness, longitudinal tensile strength and circumferential tensile strength of short fiber reinforced pipes produced by centrifugal casting method. According to the experimental test data, which were used to evaluate the effect of fiber type on the properties of fiber reinforced polyester pipe, basalt fiber reinforced pipe samples showed higher mechanical performance over E glass fiber and ECR glass fiber reinforced pipes. However, the test results of basalt reinforced polyester pipe were not as good as the individual properties of basalt fiber. Finally, by comparing the basalt fiber reinforced pipe samples having almost the same stiffness and tensile test results as E glass fiber reinforced pipe samples, the gain in fiber and resin amount were investigated. Basalt fiber reinforced pipes were slightly lighter and thinner than E glass fiber reinforced pipes. However, the decrease in the amount of the fiber and resin in basalt reinforced pipe did not result in an overall cost reduction.

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Xu, Liqun. "Integrated analysis of liquid composite molding (LCM) processes." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1095688597.

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Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xix, 245 p.; also includes graphics. Includes bibliographical references (p. 233-245).

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Caffaro, Filho Roberto Augusto. "Avaliação e identificação de toxicidade em efluente da fabricação de resinas de poliester." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254751.

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Orientador: Lucia Regina Durrant
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Os processos industriais são geradores de uma ampla variedade de contaminantes que estão presentes nas águas residuarias. A seleção de processos de tratamento baseia-se nas características do efluente a ser tratado. Neste trabalho investigou-se um efluente tóxico da fabricação de resinas de poliéster. Existem poucas informações na literatura sobre este tipo de água residuaria. Procedeu-se a caracterização do efluente, efetuando-se a avaliação e identificação de constituintes tóxicos presentes no mesmo por meio de uma abordagem orientada por toxicidade. Foi utilizado bioensaio respirometrico em lodo ativado para avaliar a toxicidade do efluente bruto. Então, foram efetuados tratamentos físicos e químicos para fracionamento do efluente, e apos cada um deles, realizou-se o mesmo bioensaio. Dessa maneira, avaliou-se qual técnica de fracionamento foi a mais efetiva na redução da toxicidade. A maior redução de toxicidade foi observada apos o fracionamento do efluente por arraste com ar em pH 11 (62,5 %). Este resultado demonstrou que uma fração significativa da toxicidade do efluente para lodos ativados era causada por compostos orgânicos volatilizados em pH 11. Isso indica que o tratamento do efluente por arraste com ar em pH básico pode ter impacto positivo em um tratamento biológico aeróbio subseqüente. Uma vez determinado o tipo de compostos no efluente que provocam efeitos tóxicos (Compostos Organicos Volateis - COVs), procedeu-se a esforços analíticos visando a identificação dos mesmos. Analises por headspace do efluente por cromatografia gasosa e espectrometria de massa identificaram a presença de aldeidos insaturados (congeneres de acroleina). Tais compostos tinham relacao direta com o efeito tóxico observado. Foram também realizados bioensaios utilizando microrganismos anaerobios. Para tanto, mediu-se o volume de gas produzido por uma biomassa anaerobia em contato com o efluente bruto e com o efluente fracionado por arraste com ar em pH 11. Não se observou redução na toxicidade do efluente mesmo com este fracionamento. Comparando-se esses resultados aos obtidos com lodo ativados, foi verificado que os compostos removidos por arraste com ar em pH 11 não apresentaram o mesmo grau de toxicidade para esta biomassa anaerobia. Tais resultados indicam que a utilização de processo de tratamento biológico anaerobio seria uma opção adequada para a condução de futuros estudos de tratabilidade deste efluente. Os resultados obtidos neste trabalho de avaliação e identificação de toxicidade em efluente da fabricação de resinas de poliéster ratificam a abordagem utilizada como uma valorosa ferramenta na caracterização de efluentes industriais tóxicos, principalmente nos casos onde não se encontram disponíveis informações especificas relacionadas ao efluente estudado
Abstract: Industrial processes generate a vast range of contaminants that are present in wastewaters. Treatment process selection is based on wastewater characteristics. In this work a toxic polyester resin manufacturing wastewater was investigated. Specific literature on this kind of wastewater is rare. The characterization of this wastewater was conducted, evaluating and identifying toxicity by applying a toxicity-oriented approach. An activated sludge respirometric bioassay was used to assess effluent toxicity. Then, physical and chemical treatments were performed for effluent fractionation. After each fractionation, the same bioassay was conducted. In this way, it was assessed which fractionation technique was the most effective in reducing effluent toxicity. The greater toxicity reduction was observed after effluent fractionation with air stripping in pH 11 (62.5 %). This result showed that a significant fraction of wastewater toxicity for activated sludge was caused by organic compounds volatilized in pH 11. This indicates that effluent treatment by air stripping in basic pH could have a positive impact in a conjugated aerobic biological treatment. Once the type of compounds causing wastewater toxicity has been determined (Volatile Organic Compounds ¿ VOCs), analytical efforts aiming the identification of these compounds were made. Wastewater headspace gas chromatographic analyses coupled with mass spectrometry identificated the presence of a,ß-unsaturated aldehydes (acrolein congeners). These compounds were directly related to the observed toxic effect. Bioassays using anaerobic microorganisms were also conducted. To that purpose, the volume of gas produced by an anaerobic biomass in contact with the baseline effluent and with the fractionated effluent by air stripping in pH 11 was measured. No toxicity reduction was observed with this fractionation. By comparing this result with the one obtained with the respirometric bioassay, it was found that the compounds removed by air stripping in pH 11 did not inhibit this kind of biomass in the same degree which they inhibited activated sludge. This indicates that the use of an anaerobic treatment process would be an adequate option for conducting future treatability studies in this wastewater. The results obtained in this research of toxicity identification evaluation of a polyester resin manufacturing effluent confirm that the toxicity-oriented approach is a valuable tool for the characterization of toxic industrial wastewaters, especially in cases when specific information related to the studied wastewater is lacking
Doutorado
Doutor em Ciência de Alimentos

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Kiehl, Julien. "Compréhension et optimisation de la dispersion du carbonate de calcium dans une résine polyester insaturée." Thesis, Mulhouse, 2012. http://www.theses.fr/2012MULH4087.

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L’objectif de ce travail est d’adapter une formulation dispersante mise au point par la société Mäder à la dispersion de carbonate de calcium (CaCO3) dans une résine polyester insaturée (UP). Le carbonate de calcium est utilisé en tant que charge dans les matériaux composites à matrice thermodurcissable et en particulier dans les SMC (Sheet Molding Compound). Le rôle de cette formulation est de diminuer les viscosités de résines UP fortement chargées tout en conservant voire en améliorant les propriétés mécaniques des composites formés par un renforcement de l’interface charge / matrice. Trois grands axes ont été développés au cours de ce travail : - le comportement rhéologique d’un mélange CaCO3/résine UP a été déterminé et la formulation dispersante a été optimisée ; - la nature des interactions entre les différents constituants de la formulation dispersante et la surface du CaCO3 a été mise en évidence ; - de nouveaux polymères permettant une dispersion plus efficace de la charge dans la résine ont été synthétisés. Le mélange CaCO3 / résine UP présente un comportement rhéologique complexe. L’optimisation de la formulation dispersante a permis d’augmenter de plusieurs pourcents le taux de charge tout en conservant des viscosités inférieures à celle autorisée par le procédé industriel. L’étude des interactions des constituants de la formulation avec le carbonate de calcium a permis de déterminer les fonctions les plus réactives et de comprendre leur interaction avec la surface de la charge. La synthèse de nouveaux dispersants a également été effectuée. Ces derniers ont ensuite été testés dans l’application et ont montré une efficacité à disperser le CaCO3 dans la résine UP
The aim of this study is to adapt a dispersive formulation developed by the Mäder group to the dispersion of calcium carbonate (CaCO3) in an unsaturated polyester resin (UP). The CaCO3 is commonly used as filler in the domain of composites especially for Sheet Molding Compound (SMC). This dispersive formulation is able to decrease the viscosity of UP resin containing a high amount of filler. In addition, the mechanical properties of composites could be increased by reinforcing the filler / matrix interface. Three main ways have been studied: - characterization of the rheological behavior of CaCO3 / polyester blends and optimization of the dispersive formulation ; - determination of the interactions between the dispersive formulation components and the CaCO3 surface ; - synthesis of new polymers in order to improve the CaCO3 dispersion in an organic matrix. A complex rheological behavior has been observed for CaCO3 / polyester blends. The dispersive formulation improvement led to an increasing of the filler percentage by keeping the viscosity under the industrial limit. The most reactive functions with the CaCO3 surface have been identified by studying the interactions between the dispersive formulation components and the CaCO3 surface. New dispersing agents have been synthesized. Their efficiency has been demonstrated for the dispersion of CaCO3 in a UP resin

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Rašner, Martin. "Technologická analýza využitelnosti nových typů termosetických materiálů pro konstrukci světlometů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-401531.

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The diploma thesis presents the usability of a new thermosetting material BMC for the construction of a car headlight. In the theoretical part there are described headlights, basic characteristics and properties of plastics focussing on polymer composite materials and material testing. The practical part deals with the processing of test samples for mechanical testing by compression moulding and also with the production of real samples of reflectors and carrier frames by injection moulding. The evaluation is based on comparison of the results of the performed tests of alternative material and the currently used BMC TETRADUR TD 492/2 in HELLA Autotechnik Nova s.r.o. Basic physical-mechanical properties such as strength, stiffness, toughness and hardness are tested and monitored. The reflectors and carrier frames are assembled into the headlight and then tested according to legal and customers´ requirements for climate and vibration resistance and photometry.

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Wakim, William. "Estudo do fosqueamento de tintas em pó, sistema poliéster/TGIC." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/46/46137/tde-20092017-110015/.

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O presente trabalho propôs-se a estudar o fenômeno de fosqueamento em filmes de tinta em pó feitos a partir de resinas poliésteres sólidas pelo sistema conhecido como Triglicidilisocianutato (TGIC). Este fenômeno é indesejado e ocorre na ocasião de mistura de lotes de tintas produzidos independentemente com resinas poliésteres sólidas que compartilham as mesmas fórmulas, especificações e processo industrial. Amostras de uma tríade de resinas poliéster, que apresenta uma particular relação de fosqueamento, foram estudadas por termogravimetria/ termogravimetria derivada (TG/DTG), calorimetria exploratória diferencial (DSC), espectroscopia de ressonância magnética nuclear de Hidrogênio (1H-RMN), cromatografia de permeação em gel (GPC), análise térmica diferencial (DTA) e espectroscopia de infravermelho com transformada de Fourier (FTIR). A partir da análise minuciosa dos resultados obtidos em cada técnica escolhida, não se notou diferenças significativas que pudessem vir a justificar o fosqueamento indesejado para os lotes estudados. Estas avaliações nos permitiram concluir que o fenômeno não ocorre por contaminação industrial dos materiais e que alguma relação latente de fosqueamento por blenda seca deve ainda ser revelada por estudo subsequente.
The present work endeavored to study the matting phenomenon of powder coatings films made of solid polyester resins through a system known as Triglycidyl isocyanurate (TGIC). This phenomenon is an undesired result and occurs when at the time of blending paint batches produced independently with polyester resins that share the same formula, specifications e industrial process. Samples of a polyester resin triad, that shared a particular matting relation, were studied by thermogravimetry/ thermogravimetry derivative (TG/DTG), differential scanning calorimetry nuclear magnetic resonance (1H-NMR), gel permeation chromatog r(aDpShCy), proton (GPC), differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR). Through in-depth analyses of all results obtained from each chosen method, no accountable differences, that could justify the undesired matting phenomenon, were noticed. These evaluations paved us the way to conclude that the studied phenomenon was not occurring due to industrial contamination, and that some latent dry blend matting relation is still to be revealed by an ensuing study.

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Oliveira, Jos? Orlando de. "Comp?sito refor?ado com sisal para aplica??o na moda." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15680.

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The objective of this research is the fabrication of a composite reinforced with dyed sisal fiber and polyester matrix for application in the fields such as, fashion, clothing, interior textiles; fashion accessories are some of the examples. For the fabrication of the composite, the sisal fibers were subjected to processes such as: chemical treatment with sodium hydroxide (NaOH) in the removal of impurities; bleaching for removing the yellowish color of the natural fiber and dyeing with direct dyes to confer the colors blue, green and orange. The search for new technologies ecologically correct has become a major concern in recent decades. Studies show that composite polymer reinforced by natural fibers is suitable for a large number of applications, and its use is advantageous in terms of economic and ecological. The dyed fibers were cut to a length of 30 mm, is used in the confection of webs. For this purpose, a web preparer by immersion, developed in the Laboratory of Chemical Textile of UFRN. The composite sheets measuring 300 x 300 x3 mm were molded by compression, with unsaturated orthophthalic polyester as matrix, and the samples in sizes 150 x 25 x 3 mm were cut with the aid of a laser machine, to be subjected to traction and flexion. The mechanical properties of traction and flexion in three points were performed in the Laboratory of metal and mechanical tests of Materials Engineering of UFRN. The resulting samples from the tests were evaluated in scanning electron microscope (SEM) at CTGas RN. On the basis of the analysis of the results from the mechanical tests, it was observed that the composite had good mechanical behavior, both in traction as in flexion. Furthermore, it was observed that in the water absorption test, the samples had a different percentage among themselves, this occurred due to the variation of density found in the fibre webs. The images of the SEM showed the failures from the manufacturing process and the adhesion of fibre/matrix. When the samples were prepared with the dyed fibers to be applied in fashion, the results were positive, and it can be concluded that the main objective of this work was achieved
A busca por novas tecnologias ecologicamente corretas tem se tornado uma grande preocupa??o nas ?ltimas d?cadas. Estudos comprovam que comp?sitos polim?ricos refor?ados por fibras naturais s?o adequadas a um grande n?mero de aplica??es e seu uso ? vantajoso em termos econ?micos e ecol?gicos. O objetivo desta pesquisa ? a fabrica??o de um comp?sito refor?ado com fibra de sisal tingida e matriz de poli?ster para aplica??o na moda: vestu?rio, t?xteis lar, acess?rios de moda etc. Para o seu beneficiamento, as fibras de sisal foram submetidas aos diversos processos: tratamento qu?mico com hidr?xido de s?dio (NaOH) na retirada das impurezas; alvejamento para remo??o da cor amarelada natural da fibra e tingimento com corantes diretos para conferir as cores azul, verde e alaranjado. As fibras tingidas foram cortadas com comprimento de 30 mm e utilizadas na confec??o das mantas. Para isso utilizou-se um preparador de manta por imers?o, desenvolvido no Laborat?rio de Qu?mico T?xtil da UFRN. Os comp?sitos medindo 300 x 300 x 3 mm foram moldados por compress?o, com poli?ster insaturado ortoft?lico como matriz, e as amostras nos tamanhos 150 x25 x3 mm foram cortadas com aux?lio de uma m?quina ? laser, para serem submetidas ? an?lise mec?nica de tra??o e flex?o. As propriedades mec?nicas de tra??o e flex?o em tr?s pontos foram realizadas no Laborat?rio de Metais e Ensaios Mec?nicos de Engenharia de Materiais da UFRN. As amostras resultantes das propriedades mec?nicas foram avaliadas no Microscopio Eletronico de Varredura (MEV) no CTG?s RN. Com base nas an?lises dos resultados dos ensaios mec?nicos, observou-se que os compositos tiveram bom comportamento mec?nico, tanto na tra??o como na flex?o. Tamb?m observou-se que no ensaio de absor??o de ?gua, as amostras tiveram um percentual diferente entre si, isso ocorreu devido ? varia??o da densidade encontrada nas mantas. As imagens do MEV mostraram as falhas provenientes do processo de fabrica??o e a ades?o fibra/matriz. Quando foram preparadas as amostras com as fibras tingidas para serem aplicadas na moda, os resultados foram positivos e pode-se concluir que o objetivo principal do presente trabalho foi atingido

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Heinrich, Lydia Alexandra. "Biosourced Coating Systems for Metallic Substrates." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1004.

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Le remplacement de monomères d'origine pétrosourcée par des analogues biosourcés améliore la durabilité et diminue la dépendance aux ressources fossiles. De plus, de nouvelles caractéristiques et propriétés sont souvent découvertes. Les polyesters aliphatiques biosourcés ont déjà partiellement remplacé les produits traditionnels. Dans le contexte du projet Sorago, une résine entièrement biosourcée pour les revêtements de prélaquage des produits intérieurs a déjà été introduite sur le marché (Estetic® bio Air, Arcelor Mittal). Pour permettre l'utilisation du produit dans des applications extérieures, sa résistance à la lumière UV et à l'humidité sont à améliorer. Cela pose deux problèmes : Une disponibilité limitée de monomères pouvant introduire de la rigidité dans la résine et la relation entre la structure de la résine et sa dégradation. La vanilline a été choisie comme synthon pour la gamme des monomères rigides et biosourcées. La transformation de sa fonction aldehyde par réaction de Perkin et sa réactivité a été examinée. Dans une série des copolymerisations, l'influence des conditions de réaction sur la composition du produit final a été proposée. Une relation structure-propriétés concernant la température de la transition vitreuse et la viscoélasticité des plusieurs monomères biosourcées a été établie, et comparée avec celle des monomères petrosourcées. Une série des prototypes avec des propriétés très variées a été soumise à un test de vieillissement rapide. Leur dégradation a été suivie sur la base de leur rétention de brillance, par FTIR et par des tests de µ-dureté et d'épaisseur des films. La performance des prototypes biosourcés s'est révélée inférieure à celle d'une résine standard pétrosourcée mais aucune évidence qui suggère que cela est du à la présence des monomères biosourcées n'a été détectée. Cela suggère que la création d'une résine biosourcée et suffisamment durable pour l'extérieur sera possible
Moving away from petroleum and towards biobased materials not only leads to greater sustainability and lower dependence on diminishing fossil resources, but can also catalyse the discovery of new properties. Aliphatic polyesters based on renewable resources have already started to replace traditional products. Within the Sorago project, a fully biobased resin for interior coil coatings has recently been proposed on the market (Estetic® Bio Air, Arcelor Mittal). In order to extend the possible use of the biobased product to exterior applications, an improvement of its resistance to humidity and UV radiation is crucial. This presents two challenges: The limited availability of monomers which provide rigidity in the resin structure and the relationship between the resin composition and its weatherability. Vanillin was chosen as a possible extension to the range of rigid, biobased monomers for polyesterification reactions. The transformation of its aldehyde and its reactivity was studied in terms of catalytic activation and through a series of copolymerisations which revealed the influence of the reaction conditions on the composition of the product. A structure-property relationship concerning the coating glass transition temperature and visco-elastic behaviour of the coating was furthermore established for a series of renewable monomers and contrasted with petroleum based equivalents. Series of prototypes with a wide variety of properties were then subjected to accelerated weathering tests. Their degradation was followed directly by gloss retention and different mechanisms were revealed using FTIR, µ-hardness and film thickness measurements. While the performance of the biobased coating was subpar, no evidence linking its degradation to the presence of renewable monomers was found, suggesting that the creation of a sufficiently durable and renewable exterior coating will be possible

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Dalibor, Ingo Hermann. "A influência de cargas particuladas nas propriedades mecânicas de compósitos com resina poliéster insaturadas." Universidade do Estado de Santa Catarina, 2013. http://tede.udesc.br/handle/handle/1641.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Particulate fillers have a broad application in the composites industry, mainly for cost reduction. But fillers may have also an influence on mechanical properties like strength, stiffness and strain. The scope of this dissertation is the mechanical characterization of particulate composites changing concentration from 1% to 20% in volume with an PVC rod as reinforcement. Initially pull out tests were applied to determine critical length of reinforcement. Critical length measures load transfer on interface between matrix and reinforcement, which is main factor to improve composite s strength. Critical length as a function of filler concentration showed a remarkable similarity for all fillers studied. At about 5% volume fraction all curves showed a minimum, it means, the shear strength is a maximum in this point. Finally, mechanical properties in flexural tests without PVC reinforcement were determined showing at low filler concentration significant variation. Statistical significance tests showed mechanical properties aren t a linear function to concentration. Flexural tests on particulate composite with PVC reinforcement showed strength reduction, but on elastic modulus and strain, different effects were realized, depending on filler used. It means, a 3 phase composite may have a synergy or dissociative effect when filler and reinforcement were applied together.
A carga particulada, normalmente utilizada para redução de custos, pode ter influência nas propriedades mecânicas dos compósitos com matriz de poliéster insaturado. Foram confeccionados corpos de prova com concentração volumétrica variando entre 1 e 20% na matriz de poliéster. Inicialmente foi analisada a força de adesão na interface do reforço e a matriz. Com a força de adesão é transferida a tensão da matriz para o reforço, ocorrendo um aumento da resistência do compósito. A força de adesão pode ser determinada pelo comprimento crítico do reforço, neste caso uma haste de PVC, através de um ensaio de arrancamento, conhecido também como pull out . A curva do comprimento crítico em função da concentração de carga mostrou uma notável semelhança com todas as cargas testadas, havendo um mínimo em torno da concentração volumétrica nominal de 5%. Posteriormente, através de ensaios de flexão, foram determinadas as propriedades mecânicas do compósito, que são o módulo de elasticidade, resistência e a deformação máxima nas concentrações acima mencionadas. Os ensaios foram realizados sem e com a haste de PVC. Os efeitos das cargas foram muito distintos em cada caso. O melhor resultado foi obtido no módulo de elasticidade do compósito com a matriz poliéster com carga de vidro moído na concentração de 5% em volume e uma haste de PVC. Nos outros casos as cargas testadas tiveram efeito negativo nas propriedades. A haste de PVC trouxe um efeito positivo apenas na deformação máxima sem a utilização de carga na matriz. Em todos os outros casos o efeito da haste de PVC foi negativo.

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Lemattre, Alexis. "Développement de résines polyester insaturées ignifugées : caractérisation des performances feu/fumées et détermination des mécanismes de décomposition." Thesis, Mulhouse, 2018. http://www.theses.fr/2018MULH2179.

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Depuis des années, les marchés des résines polyester insaturées (UP) et des composites sont en pleine expansion. En effet, grâce à la versatilité de leurs structures chimiques, les résines UP offrent un éventail de propriétés physico-chimiques et mécaniques pour le matériau final. Ces caractéristiques ainsi que leur bon rapport performance / prix expliquent l’engouement des industriels pour leur utilisation dans les composites et « gels coat » dans les domaines du bâtiment et du transport. Cependant, ces résines sont inflammables et présentent donc un risque pour leurs utilisations dans les domaines d’application accueillant des personnes. Les réglementations européennes imposent par conséquent une amélioration des propriétés feu/fumées de ces résines. La norme européenne EN45545-2 entrée en application en 2018 a pour but d’unifier les différentes normes nationales et de diminuer le risque d’incendie dans les transports ferroviaires. Les résines UP halogénées actuellement sur le marché produisent des quantités de fumées opaques et toxiques importantes. Les objectifs de ces travaux ont donc été de synthétiser et/ou d’additiver de nouvelles résines UP non halogénées et fluides possédant une tenue au feu comparable à celle des résines halogénées. La combinaison de résines UP modifiées et de retardateur de flamme (RF) additifs a été étudiée et optimisée. L’utilisation à la fois d’un RF réactif et d’un RF additif possédant un effet de synergie a permis de répondre au cahier de charges défini par le partenaire industriel. Cette résine a permis d’améliorer les performances feu/fumées du matériau composite sans impacter ses propriétés physico-chimiques et mécaniques
For many years, unsaturated polyester (UP) resins and composites markets are growing. Indeed, the wide range of UP resins gives a large physico-chemical and mechanical properties to composites. These properties and the good performance / price ratio explain the market growth of these resins in industrial applications like composites or gel coats for transportation and construction. However, UP resin exhibit low flammability and the enhancement of their fire behaviour is needed to meet the legislation and to protect goods and people. Since 2018, the European legislation for fire protection used in railway applications (EN45545-2) has strengthened and been harmonized. Smoke opacity and toxicity are the main issue of halogenated unsaturated polyester resins currently used on this market. The aims of this study were thus to develop and formulate new halogen-free and low viscosity UP resins presenting good flame retardant properties. A synergist mixture of reactive and additive flame retardants (FR) was found to be the solution to substitute brominated UP resins and meet the industrial specifications. Finally, the use of such a resin enables developing flame retardant composites without affecting their physico-chemical and mechanical properties

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Garbin, Daniel Fernando. "Efeito do material da face nas propriedades mecânicas de painéis sanduíche para aplicação rodoviária." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/157831.

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Painéis sanduíche são largamente utilizadas em diversas aplicações de engenharia e o estudo de suas propriedades é fundamental para a ampliação de sua utilização. Neste trabalho, foram estudados painéis sanduíche com núcleo de poliuretano e faces de fibra de vidro fabricados pelo processo de laminação contínua. Na primeira configuração, as faces do painel foram fabricadas com manta de fibra de vidro e resina poliéster, com 39% de teor de vidro em massa e espessura de 1,9 mm. Na segunda configuração, as faces do painel foram fabricadas com tecido de fibra de vidro e resina poliéster, com 54% de teor de vidro em massa e espessura de 1,2 mm. Realizou-se o cálculo das propriedades mecânicas de cada compósito no programa MECH-Gcomp. As propriedades do núcleo foram retiradas, inicialmente, da literatura. Então, foi possível realizar a avaliação dos painéis pelo método dos elementos finitos utilizando elementos sólidos, comparando o comportamento dos dois tipos de painéis em relação aos carregamentos de compressão de núcleo, de compressão longitudinal e de flexão. Foram realizados ensaios nas faces isoladas e também nos painéis sanduíche completos. Para as faces, os ensaios foram de teor mássico de fibra de vidro, tração, compressão e cisalhamento Iosipescu, conforme as normas ASTM D5630, D3039/D3039M, D6641/D6641M e D7078/D7078M, respectivamente. Já para os painéis sanduíche, foram realizados os ensaios de compressão de núcleo, compressão longitudinal (edgewise) e cisalhamento do núcleo utilizando flexão, conforme as normas ASTM C365/C365M, C364/C364M e C393/C393M, respectivamente. Após os ensaios, foram calibrados os modelos do MEF, permitindo que os mesmos possam calcular outras configurações similares de painel sanduíche. Foi utilizado o programa Autodesk Simulation Composite Design para realizar a validação do ensaio de cisalhamento do núcleo. Concluiu-se que a análise de elementos finitos foi confiável em representar de forma realista o comportamento dos painéis sanduíche e a redução na espessura das faces do painel pode ser compensada com o aumento da sua resistência mecânica e rigidez por meio do aumento no teor mássico de reforço e trabalhando com a orientação do mesmo.
Sandwich panels are widely used in a variety of engineering applications and the study of their properties is fundamental for the expansion of their use. In this work, we studied sandwich panels with polyurethane core and fiberglass faces manufactured by the continuous lamination process. In the first configuration, the panel faces were made of fiberglass and polyester resin, with 39% glass content by mass and 1.9 mm thickness. In the second configuration, the panel faces were fabricated from fiberglass fabric and polyester resin, with 54% glass content by mass and 1.2 mm thickness. The mechanical properties of each composite were calculated in the MECH-Gcomp software. The properties of the core were initially taken from the literature. Then, it was possible to evaluate the panels by the finite element method using solid elements, comparing the behavior of the two types of panels in relation to the core compression loads, edgewise compression and bending. Tests were performed on the faces and also on the complete sandwich panels. For the faces, the tests were fiberglass mass content, tensile, compression and Iosipescu shear, according to ASTM D5630, D3039/D3039M, D6641/D6641M and D7078/D7078M, respectively. For sandwich panels, core compression, edgewise compression and core shear using bending tests were performed according to ASTM C365/C365M, C364/C364M and C393/C393M, respectively. After the tests, the FEM models were calibrated, allowing them to calculate other similar sandwich panel configurations. It was used Autodesk Simulation Composite Design software to validate the core shear test. It was concluded that the analysis of finite elements was reliable in realistically representing the behavior of the sandwich panels and the reduction in the thickness of the panel faces can be compensated with the increase of its mechanical resistance and stiffness by increasing the mass content of reinforcement and working with the orientation of the same.

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Lamy, Yoann. "Nanostructuration de résines polyester insaturé par des copolymères à blocs : application aux composites SMC et BMC." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00812588.

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On s'intéresse dans cette étude au potentiel de copolymères à blocs (BCP) de types PBA-b-P(MMA-co-DMA) et PBA-b-P(BA-co-DMA) en tant qu'additifs multifonctionnels nanostructurant la matrice thermodurcissable polyester insaturé de composites SMC et BMC. La nanostructuration de la résine polyester insaturé (UPR) est assurée par la ségrégation du bloc élastomère poly(acrylate de butyle), ainsi que par la miscibilité du deuxième bloc dans le réseau grâce à la bonne compatibilité des motifs diméthylacrylamide (auto-assemblage). Ces BCP sont tout d'abord étudiés en tant qu'agents renforçants et anti-retrait dans les composites SMC et BMC, en étant substitués et comparés aux additifs anti-retrait conventionnels PVAc et P(MMA-co-S) incorporés traditionnellement afin de compenser le retrait de la résine polyester. Ces additifs nanostructurants sont ensuite évalués en tant qu'agents de mûrissement des compounds SMC. La nanostructuration des BCP dans la résine UP réactive pouvant entrainer une importante augmentation de la viscosité (formation d'un gel), ces additifs pourraient peut-être constituer des agents de mûrissement plus efficaces que l'oxyde de magnésium couramment utilisé à cet effet. Une étude des matrices [UPR + BCP, UPR + PVAc et UPR + P(MMA-co-S)] est réalisée dans un premier temps, les composites BMC et SMC chargés par du carbonate de calcium et renforcés par des fibres de verre étant étudiés par la suite. En absence de charges et de fibres de verre (matrice seule), la nanostructuration est moins efficace que la macroséparation de phase des additifs conventionnels PVAc et P(MMA-co-S) pour compenser le retrait du réseau polyester. Dans un composite en revanche, la nanostructuration conduit à une compensation du retrait intermédiaire entre celles du P(MMA-co-S) et du PVAc. Au niveau de la matrice seule, la nanostructuration permet d'éviter une diminution conséquente de l'énergie de rupture du réseau polyester et permet même dans certains cas une amélioration significative de cette dernière, alors que les additifs conventionnels engendrent un effondrement de cette propriété. Cette différence est cependant beaucoup moins visible dans le cas des composites, les charges entrainant une fissuration prématurée de la matrice. Un composite nanostructuré peut tout de même présenter un renforcement significatif par rapport aux composites conventionnels lorsqu'il contient des nanovides compensateurs de retrait de tailles conséquentes qui améliorent la ténacité du matériau. En ce qui concerne le mûrissement d'un compound SMC par nanostructuration au cours du refroidissement (passage de la transition ordre-désordre), si l'augmentation de la viscosité d'un système réactif UPR + BCP semble suffisamment importante et abrupte, elle est cependant insuffisante en présence des charges ou alors intervient à une température trop faible en raison de l'influence de ces dernières sur la nanostructuration.

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Galv?o, Alcione Olinto. "Desenvolvimento e an?lise de material comp?sito a base de penas de frango (fibras de queratina-KF) e matriz de poli?ster insaturado." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15670.

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Use of natural fibres as a reinforcement material in the manufacture of composites show a series of advantages: availability, biodegradability, low weight and regeneration in relation to synthetic fibres, thus justifying its utilization. In the present research work, composites were developed with chicken feathers (KF), using unsaturated polyester resin as matrix, for diversified applications, mainly in the furniture/timber industry.At present, in Brazil the chicken feathers are used as part of the animal feed, even though this material possesses low aggregated value. The chicken feathers are hollow, light and resistant. After washing with water at room temperature, a part of the chicken feathers were treated with 2% NaOH. Composites were manufactured using treated and untreated chicken feathers with unsaturated orthothalic polyester resin and 1% peroxide as catalyser, obtained in the commerce. Samples with size 150x25x3 mm for mechanical tests were cut by laser in the composite plate. Mechanical analyses were carried out in the Laborat?rio de Metais e Ensaios Mec?nicos UFRN. All the analyses were in accordance with ASTM standards. SEM analyses were also carried out on the samples.In the analyses of the results obtained, it was observed that the composites made with untreated chicken feathers showed better results (Traction 11.406 MPa and 9.107 MPa Bending 34.947 and 20.918 MPa for samples with and without treatment respectively) compared to the composite with treated feathers. Very low values of the water absorption results, evidenced the impermeability characteristic of the feathers. From the SEM images, the structure, fracture and the fibre/matrix adsorption can be evidenced. In the flammability test, it was observed that despite the feathers having sulfur as a constituent, natural inhibitor of flame, no burning support of the composites, because the manufacturing process of the composite
O uso de fibras naturais como refor?o em comp?sitos apresenta uma s?rie de vantagens: abund?ncia, biodegradabilidade, baixo peso e regenerabilidade em rela??o ?s fibras sint?ticas, justificando sua utiliza??o. Na presente pesquisa foram desenvolvidos comp?sitos com penas de frango (KF), utilizando resina de poli?ster n?o-saturado como matriz. Atualmente, no Brasil, as penas de frango s?o utilizadas como parte de ra??o animal, por?m este produto possui um baixo valor agregado. As penas s?o um material oco, leve e resistente. Ap?s a lavagem com ?gua em temperatura ambiente uma parte das penas foi tratada com 2% de NaOH. Foram fabricados dois comp?sitos, um com as penas tratadas e outro sem tratamento, usando o processo de molde fechado por compress?o, utilizando a resina de poli?ster ortoft?lica e 1% de per?xido MEK (per?xido de metil etil cetona) como iniciador, adquiridos no com?rcio local. As amostras com 150x25x3 mm de tamanho para os ensaios mec?nicos foram cortadas a laser na placa do comp?sito. Os ensaios de tra??o e flex?o em tr?s pontos foram realizados no Laborat?rio de Metais e Ensaios Mec?nicos - UFRN. Todas as an?lises estavam de acordo com as normas da ASTM. As amostras resultantes dos ensaios mec?nicas foram avaliadas no MEV. Com base nas observa??es dos resultados nos ensaios mec?nicos, (Tra??o 11,2 Mpa e 8,3 Mpa; Flex?o 34,9 Mpa e 22,9 MPa para as amostras sem e com tratamento respectivamente) observou-se que os comp?sitos refor?ados com as penas sem tratamento apresentaram um melhor comportamento quando foram expostos a carregamentos tanto de tra??o quanto de flex?o. O ensaio de absor??o evidenciou nos valores de absor??o de ?gua, uma das caracter?sticas da prote?na existente nas penas, a queratina, a sua capaciade de impermiabiliza??o a ?gua. Nas imagens do MEV foi poss?vel verificar a estrutura da pena, as regi?es de ruptura do comp?sito e a ades?o fibra/matriz. No ensaio de inflamabilidade, observou-se que apesar das penas terem como constituinte o enxofre, inibidor natural de chama, n?o houve a susten??o da queima nos comp?sitos, devido o processo de fabrica??o do comp?sito

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29

LUCIGNANO, CARMINE. "Tecnologie dei nanocompositi a matrice polimerica." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2010. http://hdl.handle.net/2108/1202.

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I nanocompositi sono una nuova classe di materiali che mostrano proprietà uniche tipicamente non condivise dai materiali convenzionali. La dispersione di particelle nanometriche, organiche o inorganiche, all’interno di una matrice polimerica può determinare l’incremento delle proprietà del composito e nel contempo può donare nuove proprietà funzionali. Il grosso interesse rivolto verso i nanocompositi dipende dalle potenzialità che tali materiali mostrano e dalle possibili applicazioni che essi possono trovare. Film rigidi o flessibili in nanocomposito, troverebbero applicazione nel packaging, vista la tendenza a conservare la trasparenza della matrice e le proprietà di impermeabilità all’ossigeno che l’utilizzo di nanocariche può determinare. Nel presente lavoro è stata messa a punto una rapida procedura di fabbricazione di film spessi in nanocomposito poliestere-montmorillonite per consentirne un’applicazione industriale. Le proprietà dinamo-meccaniche dei film sono state valutate tramite test al DMA, svolti nella particolare configurazione di trazione. I risultati ottenuti da tale prova hanno consentito di studiare la complessità dell’interazione tra nanocariche e matrice. I coatings sono spesso utili per diverse applicazioni ingegneristiche, da coating resistenti al graffio a coating che fungono da barriera termica. Poiché danni superficiali o all’interfaccia con il subtrato, possono influenzare le prestazioni finali, è importante adottare una buona tecnica di caratterizzazione per i coating. Le più recenti pubblicazioni scientifiche, a tal proposito, parlano di nanoindentazione di coating o bulk in nanocomposito. In questo lavoro viene utilizzata la tecnica di macro-indentazione strumentata per la caratterizzazione meccanica di coating, in nanocomposito poliestere-montmorillonite, depositati per spin coating su substrati in alluminio e polietilene ad alta densità. La macro-indentazione è meno sensibile alle intrinseche inomogeneità dei nanocompositi è da utili informazioni circa la resistenza dei coating. In più, in questo caso, la preparazione del campione può essere meno accurata rispetto al caso della nanoindentazione. Nell’appendice, è riportato un esempio di applicazione di macroindentazione per la caratterizzazione meccanica di materiale polimerico. In particolare il test consentiva di valutare l’effetto del contenuto locale di rinforzo in materiali polimerici caricati a gradiente. Dopo lo studio di film e coating in nanocomposito, è stato studiato il comportamento di nanocompositi nella forma di bulk. Provini bulk possono mostrare diverse proprietà rispetto ad i coating, in più, lo studio del comportamento del materiale di campioni bulk risulta più semplice e consente di approfondire alcuni aspetti. La combinazione di nanoparticelle e di una nuova tecnologia di schiumatura ha generato una nuova classe di materiali leggeri, ad alta resistenza e multifunzionali: le schiume in nanocomposito. Attualmente, risulta di grossa utilità trovare nuove, veloci ed economiche tecnologie che consentano di realizzare nanocompositi su larga scala. E’ stata sviluppata una nuova tecnologia di schiumatura per materiali termoindurenti che non richiede l’utilizzo di agenti esterni e che è stata chiamata di schiumatura allo stato solido. L’utilizzo di questa nuova tecnologia è stata utilizzata per la realizzazione di schiume nanocaricate. Lo sviluppo di materiali polimerici per applicazioni strutturali o tribolgiche, sta divenendo una domanda sempre più pressante. I compositi a matrice polimerica hanno le potenzialità per essere utilizzati per questo tipo di applicazioni; componenti in polimero, come camme, alberi e ruote dentate, sono tipicamente realizzati mediante la tecnologia dello stampaggio ad iniezione. Ciò è dovuto alla semplicità ed al basso costo di tale tecnologia che consente la realizzazione di componenti anche a geometria complessa. Tuttavia l’effetto del processo di stampaggio ad iniezione sulle proprietà di bulk di nanocompositi polimerici è ancora oggetto di studio. Nel presente lavoro, sono state studiate le proprietà tribologiche e meccaniche di di nanocompositi a matrice polimerica (PA6, PA66 and POM) , prodotti per stampaggio ad iniezione.
Nanocomposites are a relatively new class of materials with unique properties typically not shared by conventional microcomposites. The dispersion of nanometric organic or ingorganic particles in polymer matrix, may cause an increase in performances of composite materials and give new functional properties. The interest in polymer nanocomposites depends on the potential applications of these materials. Dealing with flexible or rigid films, packaging is a potential application because of the material transparency and the oxygen-barrier properties. In the present work, dynamic mechanical properties of polyester–montmorillonite nanocomposite thick films, prepared by the in situ intercalative polymerization method, were evaluated in a tensile mode. A fast fabrication procedure was chosen according to industrial applications and tensile DMA results permitted to study the interaction between nanofiller and matrix. Surface coatings are used in different engineering applications, from scratch-resisting coatings to thermal barriers. Nanocomposites have the potential for being high-performance coatings. As surface damage and interfacial failure may affect the final coating performances, the reliable characterisation of the coated film strength is critical. Recent scientific contributions mainly deal with the nanoindentation of nanocomposite coatings or bulk materials. In this work the use of instrumented macro-indentation is suggested for mechanical characterization of polyester–montmorillonite nanocomposite coatings deposited on aluminium and high-density polyethylene substrates by the spin coating method. Macro-indentation is less sensitive to material non-homogeneities and provides reliable information about the coating strength. Moreover, the sample preparation is less critical than for nanoindentation. In the appendix a particular instance of the use of macroindentation test is reported, instrumented macroindentation test was used to measure the effect of the local filler content in polymer functional graded materials . After the study of nanocomposite coatings and films, the study of bulk nunocomposites was performed to investigate the material beahviour. In fact, bulk samples exhibit different properties than coatings, moreover the study of bulk materials is easier and allow to deepen several scientific aspects. The combination of functional nanoparticles and foaming technology has generated a new class of lightweight, high strength, and multifunctional materials: the nanocomposite foams. Nowadays, the challenge is to find new fast and cheap production processes that are able to provide complex nanocomposite structures on a large scale. A new foaming technology called ‘solid-state foaming’ has recently been developed to foam thermosetting materials without using any external agent. This new technology is very easy and special equipments are not necessary. In the present work, this method was used for fabricating nanocomposite foams. Nowadays, the development of advanced materials for tribological purposes is becoming a pressing demand of manufacturing industries. Polymer-based composites have the capability of operating for a long time without lubrication in conditions of cryogenic and elevated temperatures. Components, such as gears and cams are typically produced by injection molding of thermoplastic matrix composites. In fact, the ease and economics of manufacturing complex parts by injection molding are well recognized, but the effect of the injection molding process on the bulk properties of nanocomposites is still under investigation. In this study, the author evaluated the tribological and mechanical behavior of neat and nanofilled functional polymers (PA6, PA66 and POM) produced by injectiono moulding.

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30

Kinkelaar, Mark Richard. "Dilatometric study of low profile unsaturated polyester resins /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487848078450146.

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31

Yang, Yeong-Show. "Free radical crosslinking copolymerization of styrene-unsaturated polyester resins /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487588249822242.

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Muzumdar, Shailesh Vasant. "Rheological, kinetic and volumetric characterization of unsaturated polyester resins /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487859879939704.

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Li, Ling. "Reaction kinetics of styenic/polyester resins at low temperatures /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488202171196513.

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34

Mrkos, Pavel. "Slídou modifikované elektroizolační laky." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218425.

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This master´s thesis deals with influence of mica content on the electrical properties of electrical insulating varnishes, particularly in the polyester resin Dolphon XL 2102. It focuses on diagnostic methods and testing the properties of electroinsulating varnishes. Examines the potential benefits of micronised mica in order to achieve better electrical insulation properties of the system compared to the matrix. The composite material consists of polyester resin Dolphon XL 2102, which is modified different mass percentage of micronized mica. The results of this project are frequency dependencies of real and imaginary parts of complex permitivity of varnish component.

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35

Hsu, Chih-Pin George. "Microstructure formation in free radical cross-linking copolymerization of unsaturated polyester resins." Connect to resource, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1147793760.

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Li, Wen. "Integrated analysis of low profile unsaturated polyester resins cured at low temperatures /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487951907956421.

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37

Molina, Julien. "Unsaturated polyesters synthesis for low viscosity and styrene-free resins." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R083.

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Les résines polyesters insaturées sont majoritairement utilisées dans le domaine des composites. Etant donnée la viscosité élevée de ces polyesters, il est nécessaire de les diluer avec un solvant réactif pour que la résine puisse être facilement appliquée. Le diluant réactif le plus couramment utilisé est le styrène. Les taux de dilutions sont environ de 35-39%. Cependant le styrène est étiqueté CMR et a fait l’objet d’une valeur limite d’exposition au 1er Janvier 2019. Il est donc nécessaire de réduire ou de changer de diluant réactif afin de respecter les nouvelles normes à venir. A cette fin, la structure chimique du polyester doit être optimisée via l’ajout de ramifications ou en compatibilisant la résine avec le diluant réactif. Afin de comprendre ce qui régit la viscosité d’un polymère en solution, l’étude des paramètres d’Hansen des polyesters insaturés a été menée à la fois par une détermination théorique ainsi qu’expérimentale. Une vingtaine de polyesters de structures chimiques ou masses moléculaires différentes ont été synthétisés puis leurs paramètres d’Hansen ont été mesurés via le logiciel HSPiP. La méthode QSPR a été appliquée afin de corréler l’impact de chaque monomère utilisé sur les paramètres d’Hansen du polymère. Par la même méthode QSPR, une étude de l’influence de chaque monomère sur la température de transition vitreuse des polyesters synthétisés a été réalisée. La méthode QSPR a donné des résultats très satisfaisants. Par contre la viscosité d’un polymère en solution n’étant pas un phénomène multilinéaire n’est pas corrélable par QSPR. Une méthode innovante de corrélation basée sur un réseau neuronal, a été mise en place et s’est avérée adaptée. L’étude du nombre de neurones, du nombre et de la qualité des descripteurs a permis de mettre au point un outil de prédiction de la viscosité relativement fiable vis-à-vis du nombre de données disponibles pour l’apprentissage du réseau neuronal. De plus, l’impact de chaque descripteur sur la viscosité est quantifié grâce au réseau neuronal. La compréhension de ces différents paramètres a été utilisée pour la mise au point d’une résine polyester insaturée moins visqueuse tout en gardant des propriétés mécaniques équivalentes dans le styrène par rapport à une résine « référence » vendue dans le groupe Mäder. Différents monomères ont été utilisés pour changer la structure chimique de ces polyesters. Ces polyesters ont été par la suite caractérisés par SEC, DSC, HR-MS. La viscosité en solution ainsi que les propriétés mécaniques des résines réticulées ont été mesurées. Une résine deux fois moins visqueuse par rapport à la résine référence à taux de dilution égal dans le styrène a été obtenue. Cette résine est désormais en cours d’industrialisation au sein du groupe Mäder. Parallèlement, des travaux ont été menés sur le développement d'une résine sans styrène. Afin de rendre les polyesters insaturés compatibles avec d'autres monomères, il a fallu modifier leur structure chimique afin de permettre une meilleure réticulation. Des résines sans styrène et sans odeur ont été développées au cours de cette thèse
The unsaturated polyester resins are mainly used in composites materials field. Given the high viscosity of these polyesters, it is necessary to dilute them with a reactive diluent so that the resin can be easily applied. The most commonly used reactive diluent is styrene. Dilution rates are approximately 35-39%. However styrene is labelled CMR and is subject to an exposure limit value as of 1 January 2019.It is therefore necessary to reduce or change the reactive diluent in order to meet the new standards to come. For this purpose, the chemical structure of the polyester must be optimized by compatibilizing the resin with the reactive diluent. In order to understand what governs the viscosity of a polymer in solution, the study of Hansen parameters of unsaturated polyesters was conducted by both theoretical and experimental determination. Twenty polyesters of different chemical structures or molecular weights were synthesized and their Hansen parameters were measured using HSPiP software. The QSPR method was applied to correlate the impact of each monomer used on the Hansen parameters of the polymer. By the same method QSPR, a study of the influence of each monomer on the glass transition temperature of the synthesized polyesters was carried out. The QSPR method gave very satisfactory results. As the viscosity of a polymer in solution is not a multilinear phenomenon it cannot be predicted by QSPR. An innovative method of correlation based on a neural network, has been put in place and has proved suitable. The study of the number of neurons, the number and the quality of the descriptors allowed to develop a relatively reliable viscosity prediction tool with respect to the number of data available for learning the neural network. In addition, the impact of each descriptor on the viscosity is quantified through the neural network. The understanding of these different parameters was used for the development of a less viscous unsaturated polyester resin while retaining equivalent mechanical properties in styrene compared to a 'reference' resin sold in the Mäder group. Different monomers have been used to change the chemical structure of these polyesters. These polyesters were subsequently characterized by SEC, DSC and HR-MS. Solution viscosity and mechanical properties of the crosslinked resins were measured. A resin that is two times less viscous with respect to the reference resin with a similar dilution ratio in styrene has been obtained. This resin is now being industrialized within the Mäder group. In parallel, work has been carried out on the development of a styrene-free resin. In order to make the unsaturated polyesters compatible with alternative monomers, their chemical structure had to be changed in order to allow better crosslinking. Styrene-free and odorless resins have been developed during this thesis

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38

Cao, Xia. "Integrated Analysis of Low Profile Unsaturated Polyester and Vinylester Resins Cured at Low Temperatures." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1039038413.

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39

Beaumont, Sean. "The synthesis and evaluation of inherently fire retardant/low smoke unsaturated polyester resins." Thesis, Kingston University, 1997. http://eprints.kingston.ac.uk/20603/.

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A study has been undertaken to attempt to overcome three major problems associated with common unsaturated polyester resins. These problems are the emissions of free styrene, high flammability and the emission of thick black smoke during combustion. A novel cross-linking monomer, containing two allyloxy substituents and one diethylamino substituent, has' been synthesised and purified in a two stage reaction using cyanuric chloride as the starting material. This new monomer contains five nitrogen atoms in an attempt to reduce smoke evolution and has a low volatility to reduce volatile organic emissions. It was found that this monomer was totally miscible with all resin types, based on both aromatic and aliphatic alkyds, and produced a degree of cross-linking in excess of 95% when cured with dicumyl peroxide at 90°C for 16 hrs and then 140°C for 3 hours. Combustion tests showed that the new resins produced considerably less smoke than the styrenated resins, show higher LOI values, i.e. require a higher percentage of oxygen to sustain combustion, and a lower surface spread of flame. These improved combustion properties are a direct result of the improved charring characteristics of the resins caused by the incorporation of the triazine monomer. It has been shown, however, that normal fire retardant phosphorus additives used in unsaturated polyester resins (UPRs) have little or no effect in the triazine resins and do not show any synergism with the nitrogen atoms in the new monomer. As a result of this, at high additive loading levels, the combustion behaviour improvements shown by the triazine resins over the styrenated resins are drastically reduced. It has also been shown that the triazine resins have a very high burning rate. The lack of phosphorus activity in the triazine resins has been shown to be caused by these resins thermally decomposing at low temperatures where the phosphorus is not active. This low decomposition temperature also leads to rapid decomposition and thus a high burning rate. The lack of synergism might be caused by the tertiary amine substituent being too stable towards interaction with the phosphorus additives; a primary amine might be more suitable. Mechanical studies have shown the new resin to be brittle in comparison to the styrenated resins but that it has increased Barcol hardness values, heat distortion temperature and flexural modulus.

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40

Tomuta, Adrian Marius. "New and improved thermosets based on epoxy resins and dendritic polyesters." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/129288.

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Epoxy resins constitute a class of thermosets which contains more than one epoxide group per molecule, which are very reactive to many curing agents like aromatic or aliphatic amines, acid anhydrides or isocyanates. They are used as reinforced composites, adhesives, high performance coatings and encapsulating materials. Epoxy thermosets have excellent electrical and mechanical properties, good adhesion to many metals and resistance to moisture and thermal and environment exposure. Curing agents that show no activity under normal conditions but show activity by external stimulation, like temperature, can be called ’’latent curing agents”. Among the thermal latent curing agents dicyandiamide (DICY) is one of the most employed in epoxy resin technology. The latent nature of this type of curing agents is due to the insolubility in epoxy resins at room temperature. The use of dihydrazides as curing agents has been scarcely reported in scientific literature but there are some dihydrazides commercially available as latent curing agents. In the present study a series of dihydrazides with different structures were prepared by reaction of dicarboxylic diester with hydrazine hydrate in ethanol. These compounds were studied as curing agents in DGEBA/dihydrazide 2:1 (mol/mol) formulations demonstrating their latent character. In the dihydrazides we have prepared, with aliphatic, cycloaliphatic and aromatic moieties a relationship between the melting point of the dihydrazides and the initial curing temperature was observed with the exception of the cycloaliphatic dihydrazide, which was amorphous but initiate the cure at the highest temperature.
En esta tesis, hemos sintetizado y caracterizado una familia de dihidrazidasque han sido utilizadas en el curado térmico de resinas epoxi (DGEBA). Asimismo, se han sintetizado nuevos poliestereshiperramificados con grupos finales no reactivos como modificantes de resinas epoxi, curadas con dihidrazidas y con anhídridos y se han caracterizado los termoestables obtenidos. También hemos sintetizando estructuras dendríticas tipo estrella con núcleos de poliéster aromáticos y brazos de policaprolactona. Estas estructuras se han utilizado como agentes modificantes de sistemas epoxi/anhídrido y epoxi/triflato de iterbio. Se ha podido demostrar la mejora de la tenacidad en los materiales termoestables y de su degradabilidad química, manteniendo sus buenas características termomecánicas.

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41

Nalampang, Kanarat. "Cure kinetics of unsaturated polyesters : a fundamental approach to the understanding of the microstructure of unsaturated polyester resins and its influence on their cure kinetics with styrene and the properties of the cured products." Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418782.

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42

Phillips, M. J. "Composistion-morphology-mechanical property effects and the antishrink mechanism in low profile modified unsaturated polyester thermosetting resins." Thesis, Cranfield University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305379.

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43

Ghorbel, Ilhem. "Mécanismes d'endommagement des tubes verre-resine pour le transport d'eau chaude : influence de la ductilité de la matrice." Paris, ENMP, 1990. http://www.theses.fr/1990ENMP0232.

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Ce travail traite des mécanismes d'endommagement des tubes verre/résines destines au transport de l'eau chaude a 60#oc. L'influence de la ductilité de la matrice, du vieillissement hygrothermique, des impacts et de certaines sollicitations mécaniques sur le comportement de ces composites y sont considérées. L'objectif de cette étude est de prédire une durée de vie de ces canalisations devant véhiculer de l'eau a 60#oc et a 6 bars pendant 30 ans. Les structures composites étudiées sont obtenues par enroulement filamentaire (=55#o). Ces matériaux proviennent de deux fabrications se différenciant par la ductilité de leur matrice: polyester-fibres de verre e, et vinylester-fibres de verre ecr. L'endommagement est mesure par chute des rigidités à l'aide d'extensomètres spécifiques, et par le biais de l'émission acoustique et des observations microscopiques. Dans un premier temps, l'influence du vieillissement hygrothermique, par immersion dans l'eau a 60#oc, sur les propriétés physico-chimiques des résines pures et renforcées a été étudiée a partir des mesures gravimétriques, et des essais de dsc, de dma et d'i. R. L'importance de la morphologie de la matrice, de sa régularité structurale, et de la présence des fibres ont été mises en évidence. Dans un second temps, des essais de traction uniaxiale en monotone et en dynamique ont été conduits sur des éprouvettes plates. Les caractéristiques de chacun des constituants, de la couche, et du stratifie (55#oc) ont été mesurées. L'évolution des caractéristiques mécaniques de la couche au cours du vieillissement hygrothermique en fonction de l'évolution des propriétés physico-chimiques a été établie. La modélisation du comportement mécanique du stratifie est abordée dans ce travail. Ainsi, dans le domaine des faibles déformations le comportement des composites est viscoélastique linéaire alors qu'une non-linearite est observée dans le domaine des con

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Širjovová, Veronika. "Optimalizace plazmatických povrchových úprav skleněných vláken." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401847.

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Diploma thesis deals with glass fiber surface modification using plasma-enhanced chemical vapor deposition in order to prepare functional interface that enhances the properties of polymer composites. The effect of deposition conditions on shear strength was observed with respect to the chemical composition of the deposited film. Thin films were deposited on planar substrates and fibers using monomer tetravinylsilane in a mixture with oxygen at selected power of plasma discharge. Chemical composition of prepared material was analyzed by infrared spectroscopy. Planar substrate film adhesion was measured using the scratch test. The composite sample was prepared by embedding the surface modified fibers in unsaturated polyester resin, followed by the curing process. The cured composite sample underwent the short beam shear test.

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Johansson, Katarina. "Thermally cured coil-coatings utilizing novel resins and fatty acid methyl esters as reactive diluents." Doctoral thesis, KTH, Fiber- och polymerteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4857.

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Solvent-borne thermally cured coil-coating resins contain large amounts of volatile organic solvents in order to obtain suitable flow for film application. This work describes how the expensive and environmental hazardous volatile organic solvent content of a solvent-borne thermally cured polyester/melamine coil-coating system can be reduced by introduction of fatty acid methyl esters (FAMEs) as reactive diluents and modification of the polyester binder resin. The evaluated reactive diluents, two rape seed methyl esters (RMEs), two linseed oil methyl esters (LMEs), and a tall oil methyl ester (TOME) have been evaluated both in a fully formulated clear-coat system and via model studies. Viscosity measurements of wet paint mixtures showed that formulations with hyperbranched polyester binder hold lower viscosity than conventional polyester binder resins and that FAME works as a diluent. Fully formulated clear-coats were cured under simulated industrial coil-coating cure conditions and in a convection oven at lower temperatures respectively. FAME increases the mobility of the system enhancing the film formation process. Free-standing clear-coat films were analyzed with Raman, carbon-14 dating, extraction, dynamic mechanical analysis, and visual observation. Incorporation of FAME could not be confirmed by Raman analysis. However, carbon-14 dating indicated the presence of FAME that could not be extracted from the films. The mechanical properties of the films were also affected by the addition of FAMEs, oven temperature, choice of co-solvent, and flash-off period. Conventional film characterization tests on substrate supported coatings indicated that binder resin structure and cure conditions affect the final film properties. Model studies were performed to clarify how FAME can chemically react through transesterification with the hydroxyl-groups of the polyester. The transesterification reaction between different FAMEs and primary alcohols with and without tertiary hydrogen was monitored with 1H-NMR and real time IR. Evaporation and side reactions, e.g. alkene reactions, are competing factors to the transesterification reaction. The study showed that fatty acid structure, reaction time, and temperature affect the transesterification conversion, degree of side reactions, and choice of catalyst. A pigmented fully formulated polyester/melamine formulation with a reactive diluent was cured at full scale in an industrial coil-coating production facility. Evaluation of the final film properties showed that the coating fulfills the specification of conventional polyester/melamine coil-coating systems.
QC 20100817

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46

Marais, Stéphane. "Etude de la diffusivite et de la solubilite de l'eau dans une resine polyester insature. Cinetiques de sorption et etablissements des flux de permeation." Paris 6, 1998. http://www.theses.fr/1998PA066562.

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Ce travail fait suite a une etude comparative du comportement a l'eau de differentes resines polyesters insatures. Celles-ci sont utilisees dans de nombreux domaines et en particulier en tant que revetement protecteur (gels-coats). Les resultats anterieurs avaient mis en evidence des particularites dans la diffusion de l'eau, qu'il convenait d'etudier de maniere plus approfondie. Pour cela, nous avons choisi une resine tres representative dont la caracterisation a permis de montrer sa stabilite chimique et un effet plastifiant de l'eau. Les cinetiques de sorption et les mesures de permeation ont ete les deux methodes complementaires d'investigations pour comprendre les mecanismes de diffusion de l'eau dans notre polymere. Les sorptions ont ete realisees a l'aide d'une microbalance a suspension electromagnetique. Dans l'hypothese d'un equilibre local instantane, elles s'interpretent sur la base d'un accroissement du coefficient de diffusion avec la concentration de l'eau. Les permeations ont ete realisees a partir d'un permeadiffusiometre que nous avons elabore et mis au point au laboratoire. Il permet d'analyser le regime d'etablissement et d'acceder a la permeabilite en regime stationnaire. Les resultats ont ete discutes et confrontes a la theorie. La loi d = d oe c, avec coefficient de plastification, semble bien convenir pour decrire l'allure de l'etablissement du flux. Cependant, une etude en fonction de l'activite de l'eau ne s'accorde pas avec un coefficient constant. D'autre part, les solubilites a l'equilibre de sorption et la permeabilite p (etat stationnaire) conduisent a des valeurs de coefficients de diffusion (d e q = p/) plus elevees et fonction decroissante de la teneur en eau. Cette variation est compatible avec une sorption de type flory-huggins qui rend compte de la formation d'agregats de molecules d'eau. L'ensemble des resultats pourrait s'expliquer par une double dependance du coefficient de diffusion avec la concentration et le temps. L'equilibre local ne serait pas instantane du fait de phenomenes tels que la relaxation du materiau vitreux. A titre d'application, nous avons mis en evidence un accroissement de l'effet barriere resultant d'un traitement de surface par plasma froid.

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Liba, Ademir Donizeti. "Controle da finalização da reação de resina de poliester insaturado via NIR." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267690.

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Orientador: João Sinezio de Carvalho Campos
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-04T01:48:34Z (GMT). No. of bitstreams: 1 Liba_AdemirDonizeti_M.pdf: 4797015 bytes, checksum: 1351ff08893b1a29731246cf2e4cd3c8 (MD5) Previous issue date: 2004
Resumo: A resina de poliéster insaturada (RPI) é um polímero termofixo de baixo peso molecular obtido por condensação, o processo inicia-se através da esterificação entre diálcoois e diácidos saturados e insaturados, com o aumento do peso molecular do polímero, a retirada da água, que é gerada como subproduto da reação, torna-se difícil e lança-se mão do uso do vácuo ou de um maior fluxo de gás inerte para finalização da reação. Quanto à produção em escala industrial, apesar de conhecerem-se métodos de produção contínua, esta na maioria das indústrias é conduzida em bateladas com tempo de duração em média de 20 horas, podendo variar de acordo com a escolha das matérias primas utilizadas. Para a obtenção do polímero dentro dos parâmetros especificados, se faz necessário o controle dos radicais carboxilas, medidos através do índice de acidez (IA) e do peso molecular médio numérico (Mn), sendo este último parâmetro obtido de maneira indireta através da viscosidade(n). Para a viscosidade pode-se utilizar a escala Gardner, ou o viscosímetro cone e placa. A marcha de execução destas técnicas envolve várias etapas, desde a retirada da amostra até a obtenção do resultado da medida, sendo que para a amostragem, dependendo do equipamento disponível, esta pode implicar na interrupção do processo produtivo. Neste trabalho apresenta-se uma alternativa para o controle da reação, através do infravermelho próximo (NIR), em substituição às técnicas convencionais, com a vantagem do acompanhamento e do controle ser passível de execução em tempo real e sem a necessidade da retirada de amostras. Utilizou-se como base para o trabalho, a utilização anterior do NIR em processos envolvendo outros polímeros, tais como o policloreto de vinila (PVC), o policarbonato, o poliuretano e outros. Para verificar-se a viabilidade da utilização do NIR em substituição as técnicas convencionais, os valores obtidos para o IA e a viscosidade através destas técnicas foram comparados estatisticamente aos valores obtidos pelo NIR, obtendo-se forte correlação, com confiabilidade estatística de 95%. Com os resultados obtidos concluiu-se que o NIR pode ser utilizado com vantagens para o controle do processo de obtenção da resina de poliéster insaturada
Abstract: The unsaturated polyester resin (UPR) is a thermosetting polymer of low molecular weight obtained by condensation, the process begins through a esterification, between glycols and a mix of saturated and unsaturated acids, when the molecular weight of the polymer increase, the retreat of the water, generated as by-product of the reaction, if it turns more difficult and are necessary to use a vacuum or a larger flow of inert gas for finalization of the reaction. The production in industrial scale, in spite of they know each other methods of continuous production, are made in a batch with 20 hours long, could vary in agreement with the choice of the raw materials. For the obtaining of the polymer in the specified parameters, are necessary the control of the acid number (AN) and of the molecular weight (Mn), being this last obtained parameter in an indirect way through the viscosity. For measures those properties, are used as tools for the measure of the acidity number by titrimetric methods, and for the viscosity are use the Gardner scale, or the cone and plate viscometer. These techniques involves several stages, from the take of the sample to the obtaining of the result of the measure, and for obtain the sampling, depending on the available equipment, this can implicate in the interruption of the productive process. In this work we propose an alternative for the control of the reaction, by near infrared spectrometer (NIR), in substitution to the conventional techniques, with the advantage of the attendance and of the control to be susceptible to execution in real time and without the need of take samples. It was used as base for the work, the previous work of NIR in processes involving other polymeric materials, such as polyvinyl chloride (PVC), polycarbonate, the polyurethane and others. To verify the viability of the use of NIR in substitution of the conventional techniques, the values obtained for acid number and viscosity through these techniques were compared to the values obtained by NIR, being obtained strong correlation, with statistical reliability of 95%. With the obtained results it was ended that NIR can be used with advantages for the process control of unsaturated polyester resin
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química

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OU, ZHEN-FANG, and 歐珍方. "Evaluation of unsaturated polyester resin from reclaimed PET." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/53176055967051046836.

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Chin, Shih-Yuan, and 秦士淵. "Modification of saturated polyester resin for improvement of thermal resistance." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/r47mkv.

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碩士
國立臺北科技大學
有機高分子研究所
100
In this study, thermal resistant staurated polyester resin is composed of three different kinds of polyester resin monomer, which are mixed with solution (Toluene:MEK=4:1) to form polyester resin solution. After adding silane coupling agent (GOTMS) or curing agent (including NCO functional group), the solution is coated by doctor blading on the PET film to make the layer of insulation for Flexible Falt Cable(FFC). The goal of this study is to improve adhesion between layer of insulation and metal conductor interface under the heat shrinkage of PET film in the high temperature production. The purposes of the study are achieved by increasing the sability and thermal resistance of the polyester resin. Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analymer (DMA) are used to obtain thermal properties and glass transition temperatures (Tg).Thermal Gravimetric Analysis (TGA) test is used to obtain pyrolysis temperature. FT-IR is used to observe the functional group of polyester resin. The Universal Testing Machine is used to obtain adhesive and tension. This study concludes that glass transition temperature of resin can be increased by adding curing agent, the adhesion can be increased by adding coupling agent.

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CAI, JIA-XIONG, and 蔡嘉雄. "Study in physical properties of polyurethane-modified unsaturated polyester resin." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/03780764077868223008.

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Dissertations / Theses on the topic 'Polyester resin'

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