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Dissertations / Theses on the topic 'Thermoset resin'
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Duffy, Christopher M. "The application of on line modification of resin kinetics to resin transfer moulding." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263410.
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Krall, Eric. "Development of Novel Kraft Lignin Resin for Use in Thermoset Materials." Diss., North Dakota State University, 2019. https://hdl.handle.net/10365/29551.
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Scott, Brian Cameron. "Evaluation of Phenol Formaldehyde Resin Cure Rate." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/33222.
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Cure time is often the bottleneck of composite manufacturing processes, therefore it is important to understand the cure of todayâ s thermosetting adhesives. This research attempts to characterize the cure rate of two commercial phenol-formaldehyde adhesives. Two methods are used, parallel-plate rheometry and dielectric spectroscopy. Viscosity data from a parallel-plate rheometer may be used to track the advance of polymerization as a function of temperature. This data can then be used to optimize press conditions and reduce production times and costs.
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The research will further examine resin cure through dielectric analysis; such a technique could monitor resin cure directly and in real-time press situations. Hot-pressing processes could conceivably no longer require a set press schedule; instead they would be individually set based on dielectric data for every press batch. Such a system may lead to a more efficient and uniform product because press times could be based on individual press cycles instead of entire product lines. A more likely scenario, however, is the use of in situ adhesive cure monitoring for troubleshooting or press schedule development.</p><p>
This research characterized the cure of two phenol-formaldehyde resins using parallel-plate rheometry, fringe-field dielectric analysis, and parallel-plate dielectric analysis. The general shape of the storage modulus vs. time curve and the gel and vitrification points in a temperature ramp were found.</p><p>
Both dielectric analysis techniques were able to characterize trends in the resin cure and detect points such as vitrification. The two techniques were also found to be comparable when the cure profiles of similar conditions were examined.</p><br>Master of Science
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Benson, Margaret. "Disposal of thermosetting plastics." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310518.
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Haghshenas, Seyed Mehdi. "Integrating resin flow and stress development in process modeling of thermoset composites." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43758.
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The usual approach to the process modeling of thermoset matrix composites is to divide the analysis into two distinct and sequential steps, first of flow-deformation behaviour and then of stress-deformation. In the current processing models, each of these two aspects is dealt with in a separate sub-model, typically called the flow module and stress module respectively. The flow module is relevant to the pre-gelation behaviour of resin, while the stress module is valid for the post-gelation composite material.
In this thesis, the framework to integrate the flow and the stress modules into a unified module in finite element processing models is presented. The work is based on a two-phase model for analysis of resin flow and its resulting deformations in the composite material. Special measures are introduced to provide for additional capability of this model to account for the development of stresses in the curing composite material. These modifications are needed to ensure the accuracy of the model in both of resin flow and stress development regimes, and include the introduction of consistent compressibility in the mass conservation equation of the two-phase system, and a special decomposition of stresses of the system.
The formulation is implemented for a pseudo-viscoelastic stress model in a 2D plane strain FE code in MATLAB. The approach may readily be extended to fully viscoelastic models. Various examples from single-element problems dealing with the development of residual stresses throughout a single-hold cure cycle to more geometrically complex composite laminates undergoing standard cure cycles are modeled by the integrated model and comparisons are made in one extreme to the flow-compaction behaviour by the standard flow models, and in the other extreme to the results obtained by the pseudo-viscoelastic approach.
The model developed here is a promising tool for simulating processing of large-scale composite structures continuously from the very early stages of the process when the resin behaves in a fluid-like manner all the way to the final stage when it behaves as a 3D solid.
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Esmaeili, Nima, and Shahrzad Javanshir. "Eco Friendly Composites Prepared from Lactic Acid Based Resin and Natural Fiber." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17524.
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Lactic acid based thermoset were synthesised by reacting lactic acid with glycerol andfunctionalizing lactic acid branches by methacrylic anhydride. Resins with different chainlength were prepared and their thermo mechanical properties were examined through DMAanalysis and their molecular structures were analyzed by NMR method and their viscositywere investigated through rheometry analysis and three monomers were selected as the bestchain length. Degree of reaction in different reaction times was evaluated by a modifiedtitration method and bulk preparation of resin was performed by optimal process condition.DSC analysis was conducted in order to evaluate curing behaviour of resin with benzoylperoxide as cross-linking initiator. TGA analysis was performed to check thermo stability ofthe resin. Bio composites by viscose unidirectional and bidirectional knitted fabrics and alsonon woven viscose fiber with different fiber loads were prepared by ordinary hand layupimpregnation followed by compress moulding and their mechanical and thermo mechanicalproperties were characterized by tensile, flexural, charpy and DMA analysis and optimumfiber loads were identified for each fiber type. Ageing properties of prepared composites wereexamined by placing samples in climate chamber to simulate long time ageing and ageingexperiment was followed by tensile and flexural test to evaluate mechanical properties afterageing simulation. Composite`s swelling properties for water and some other solvents wereinvestigated and also their chemical resistance were evaluated by immersing them in 1M HCland KOH. The resin was also compared with a commercial oil based thermoset by preparingglass fiber reinforced composites and also effect of adding styrene to the resin were evaluated.Results of this work demonstrated that the novel synthesised have very high mechanical andthermo mechanical properties surpassing commercial oil based poly esters but ageingbehaviour is not very good however adding styrene can improve ageing properties. Also theresin is compatible with cellulosic natural fibers and forms strong composites.<br>Program: Masterutbildning i energi- och material
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Foix, Tajuelo David. "Hyperbranched polymers and other highly branched topologies in the modification of thermally and uv cured expoxy resins." Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/52795.
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RESUM
Les reïnes epoxi constitueixen un dels polímers més emprats en el món de la industria, si bé presenten una sèrie d’inconvenients, els més importants dels quals són: la seva inherent fragilitat, la seva excessiva resistència tèrmica que en dificulta l’eliminació d’un substrat un cop finalitzada la seva vida útil i l’encongiment que experimenten durant el procés de curat. Per tal de reduir o eliminar aquests problemes aquesta tesi proposa l’ús de polímers hiperramificats així com polímers estrella i copolímers lineal-hiperramificat de bloc com a modificants químics de reïnes comercials. Amb aquesta estratègia s’han aconseguit millorar la tenacitat degut a efectes flexibilitzants o a separacions de fase del modificant en la matriu epoxídica, així com reduir l’encongiment en el curat o la degradabilitat de les reïnes, sense afectar altres propietats de la reïna com la seva Tg o la seva duresa.<br>ABSTRACT
Epoxy resins are one of the most used polymers in the field of technological applications. However, they present some drawbacks being the most important the following: they are inherently brittle materials; they present excessive thermal resistance that limits their reworkability; and the shrinkage they experiment during curing. To overcome these problems this thesis proposes the use of hyperbranched polymers, as well as star polymers and lineal-hyperbranched block copolymers as chemical modifiers of commercially available epoxy resins. With this strategy tougher materials have been obtained due to either a flexibilizing effect or a phase separation of the modifier within the epoxy matrix. Moreover, the shrinkage on curing and the degradability of the thermosets have been improved without compromising other properties of the resin such as its Tg or its hardness.
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Kazilas, Michalis C. "Acquisition and interpretation of dielectric data for thermoset cure monitoring." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/97.
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The interpretation and modelling of the dielectric response of thermosetting materials during cure was the main focus of this study. The equivalence of complex permittivity and complex impedance in terms of information content was outlined in a series of case studies covering the separate effects of dipolar movements and charge migration as well as the combined effect of the two polarisation mechanisms. Equivalent electrical circuits were used in order to model the evolution of the complex impedance during cure. A numerical method that can model consecutive spectra throughout the cure was developed. The method is based on Genetic Algorithms and requires only input from the modelling of the initial spectra. Complex impedance spectra were collected during the cure of a commercial epoxy resin formulation under isothermal and dynamic heating conditions. The spectra were analysed and modelled. The modelling was successful over the whole frequency range of the measurements (1 Hz – 1 MHz). The analysis of the estimated model parameters showed that charge migration dominates the dielectric response in a wide frequency range. In addition, the modelling algorithm also distinguished between the effects of electrode polarisation and dipolar movements in the signal. A new equivalent circuit was used in order to map the frequency regions where the each one of the three phenomena that together comprise the dielectric signal can be monitored most effectively. A chemical cure kinetics model was developed for the studied system. A correlation between the maximum point of the imaginary impedance spectrum and the reaction conversion was established. A mathematical model, based on a simple linear dependence of the dielectric signal on conversion and temperature, was built. The model predictions agreed well with the experimental data. The aim of simplifying the interpretation of the dielectric signals led to the development of a new experimental technique. Temperature Modulated Dielectric Analysis employs temperature modulations superimposed on an underlying thermal profile in order to separate the influence on the signal of the temperature alone from that of the cure reaction. The early study carried out here shows that such measurements are feasible and reveals important issues for its further development.
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Zeytin, Cigdem. "Synthesis And Characterization Of Epoxy-acrylate Vinylester Resin And Network Structure." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610115/index.pdf.
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Vinylesters are termosets resins that have reactive double bond at the chain ends. They are produced by the reaction of various epoxies and acrylic acids by step growth polymerization. Vinylester chains are oligomers with molecular weight from 600 to 1200 g/mol. The resin viscosity is very high<br>therefore, diluent is used for easy application. The generally used diluent is styrene with, reactive double bonds to form a crosslink between the chains. The diluted resin viscosities are between 200 &<br>#8211<br>2000 cps. Peroxide initiators are used for network formation. The mechanical properties of vinylester resin are enhanced with reinforcements such as glass fiber, carbon fiber, Kevlar or nanoparticules to make composites.
Various molecular weights of vinylester resins were synthesized and the samples were prepared with different styrene contents. The effects of the styrene content, temperature and molecular weight on the viscosity were measured and examined. The main effects were determined as styrene content and temperature, while the effect of molecular weight is negligible. The resins were characterized with IR and NMR spectroscopy. The molecular weights were determined by theoretical calculations, titration and H-NMR spectroscopy.
Peroxide initiators were used to cure the resins with the cobalt complex accelerator. The resins were post-cured at different temperatures. The completion of the curing was monitored by the disappearance of the carbon-carbon double bonds of methacrylate (943 cm-1) and styrene (910 cm-1), by FT-IR spectrum.
The effects of styrene content, post-cure conditions, and molecular weight on the mechanical properties were discussed. The glass transition temperatures were determined by DSC and DMA. The crosslink densities and rheological properties were determined by creep test. The important properties of vinylester resins, which are modulus, tensile and flexural strength, shrinkage, water absorption, glass transition temperature, HDT values and impact strength were investigated.
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Fan, Zhihang. "Flow and rheology of multi-walled carbon nanotubes thermoset resin suspensions in processing of glass fiber composites." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 254 p, 2007. http://proquest.umi.com/pqdweb?did=1362534231&sid=8&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Chen, Rong. "Synthesis and characterization of tall oil fatty acid based thermoset resin suitable for natural fiber reinforced composite." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-16591.
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Biobased thermoset resins were synthesized by functionalizing the tall oil fatty acid with hydrogen peroxide and then methacrylic anhydride. The obtained resins were characterized by FTIR to confirm the conversions. The cross-linking ability of the resins were checked by curing experiments and followed by DSC analysis regarding the extent of cross linking. TGA analysis was conducted to identify the thermal degradation patterns of cured resins. The obtained resins (blended with or without 33wt% styrene) were used as matrix and knitted viscose fibers were used as reinforcements to make bio-based composites. Ten layers of knitted viscose fibers were stacked crosswise (0/90⁰С) and hand lay-up impregnation was performed. The fiber ratio of all composites was around 63-66%. The composites were characterized by flexural testing, dynamic mechanical thermal analysis and charpy testing. This work demonstrates that manufacture of composites with both matrix and reinforcement fiber coming from renewable resources is feasible, and the resulted composites have satisfied mechanical performance.<br>Program: MSc in Resource Recovery - Sustainable Engineering
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Ghoreishi, Rima, and Fatmehsari Mehdi Ehsani. "Mechanical and Thermal Characterizations of Biobased Thermoset Resins from Soybean Oil Reinforced with Natural Fiber Using Vacuum Injection Moulding Technique." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20223.
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The aim of this research was to analyze the mechanical and thermal properties of composites andhybrid composites prepared with four types of jute fibers and two different resins; biobased thermosetresins acrylated epoxidized soybean oil (AESO) and mathacrylated anhydride modified soybean oil(MMSO). The processing technique used was vacuum injection molding (VIM). Tensile and, flexuraltestings and dynamic mechanical and thermal analysis (DMTA) were used to characterize thecomposites’ properties. The results showed that the AESO composites have better tensile and flexuralproperties. This may be due to the fact that the curing conditions were quite the same for both AESOand MMSO composites but MMSO composites showed different behavior during curing step. Theywere completely cured in a shorter time compared to AESO composites. Having equal curing time forboth resins’ composites can damage the structure of MMSO composites and hybrids. Tan delta peak forthe MMSO reinforced composites occurs at higher temperatures, compared to AESO reinforcedcomposites, which means better thermal properties for MMSO reinforced composites.
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Kukadia, Umesh. "ROOM TEMPERATURE CURING OF BIO-BASED RESINS AND PREPARATION OF THEIR COMPOSITES." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19028.
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In today’s world the significance of bio-based materials are increasing rapidly because ofthe environmental concern. Material scientists are nowadays engaged in development ofsuch materials which have natural origin and degrade in its environment. Several workshave already been reported in area of thermoplastic biocomposites. However biocompositesbased on thermosets is comparatively new area of research. In this work biobasedcomposites have been developed from two different bio-based thermoset resins.The main objective of the work was room temperature curing of poly lactic acid basedresin (POLLIT™) and AESO, acrylated epoxidized soy-bean oil (TRIBEST®). These tworesin systems were impregnated with different natural fibre mats. Cure behavior wascharacterized by means of DSC (Differential Scanning Calorimeter) and results showsthat the resins have been cured at room temperature. The mechanical properties ofprepared composites were assessed by the means of flexural testing and charpy impacttesting. The viability of using these composites in structural applications are also beendiscussed.<br>Uppsatsnivå: D
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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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Rosario, Astrid Christa. "The Chemistry of Dimethacrylate-Styrene Networks and Development of Flame Retardant, Halogen-Free Fiber Reinforced Vinyl Ester Composites." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/11228.
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One of the major classes of polymer matrix resins under consideration for structural composite applications in the infrastructure and construction industries is vinyl ester resin. Vinyl ester resin is comprised of low molecular weight poly(hydroxyether) oligomers with methacrylate endgroups diluted with styrene monomer. The methacrylate endgroups cure with styrene via free radical copolymerization to yield thermoset networks. The copolymerization behavior of these networks was monitored by Fourier Transform Infrared Spectroscopy (FTIR) at various cure conditions. Reactions of the carbon-carbon double bonds of the methacrylate (943 cm-1) and styrene (910 cm-1) were followed independently. Oligomers possessing number average molecular weights of 700 g/mole were studied with systematically increasing levels of styrene. The Mortimer-Tidwell reactivity ratios indicated that at low conversion more styrene was incorporated into the network at lower cure temperatures. The experimental vinyl ester-styrene network compositions deviated significantly from those predicted by the Meyer-Lowry integrated copolymer equation at higher conversion, implying that the reactivity ratios for these networks may change with conversion. The kinetic data were used to provide additional insight into the physical and mechanical properties of these materials.
In addition to establishing the copolymerization kinetics of these materials, the development of halogen free fiber reinforced vinyl ester composites exhibiting good flame properties was of interest. Flame retardant vinyl ester resins are used by many industries for applications requiring good thermal resistance. The current flame-retardant technology is dependent on brominated vinyl esters, which generate high levels of smoke and carbon monoxide. A series of halogen free binder systems has been developed and dispersed in the vinyl ester to improve flame retardance. The binder approach enables the vinyl ester resin to maintain its low temperature viscosity so that fabrication of composites via Vacuum Assisted Resin Transfer Molding (VARTM) is possible. The first binder system investigated was a polycaprolactone layered silicate nanocomposite, which was prepared via intercalative polymerization. Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) data indicated a mixed morphology of exfoliated and intercalated structures. The mechanical properties and the normalized peak heat release rates were comparable to the neat vinyl ester resin.
Alternative binder systems possessing inherent flame retardance were also investigated. A series of binders comprised of novolac, bisphenol A diphosphate, and montmorillonite clay were developed and dispersed into the vinyl ester matrix. Cone calorimetry showed reductions in the peak heat release rate comparable to the brominated resin.<br>Ph. D.
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Zonatti, Welton Fernando. "Estudo interdisciplinar entre reciclagem têxtil e o design: avaliação de compósitos produzidos com fibras de algodão." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/100/100133/tde-13032013-015305/.
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Visando o gerenciamento dos artigos têxteis advindos do descarte doméstico e dos refugos gerados nos processos de fabricação, a reciclagem e a reutilização surge como uma resposta emergencial aos problemas ambientais do setor de têxtil e moda. O presente estudo teve como principais objetivos realizar uma revisão bibliográfica sobre técnicas de reuso e reciclagem de têxteis, principalmente das fibras de algodão, bem como temas relacionados à ecologia industrial, ao design de moda e ao eco design. Na sua parte experimental também visou realizar ensaios de microscopia e de determinação de regain da fibra de algodão, bem como ensaios de tração, alongamento e microscopia em compósitos produzidos com três diferentes tipos de resinas termorrígidas (epóxi, poliéster ortoftálico e poliuretano) reforçadas com fibras têxteis de algodão, sugestão possível para a diminuição dos refugos têxteis em aterros sanitários. Para tais compósitos foram apontadas aplicações no setor de moda. Conclui-se que os compósitos produzidos a partir de resíduos têxteis poderiam trazer benefícios ao meio-ambiente, pois além de possuírem atribuições como resistência e coesão, podem ser destinados à área de moda, entre outras áreas, pelos atributos visuais que proporcionam. Assim, são capazes de suprir necessidades específicas de consumo do mercado, ávido por novidades, bem como de suprir a demanda por estudos de novos materiais no setor de têxtil e moda, que carece de bibliografia especifica que reúna uma análise técnica e estética abrangendo todas as fases produtivas de materiais, processos, criação e design.<br>Aiming management of textiles coming from household waste and scrap generated in the manufacturing processes, recycling and reuse arise as emergency responses to the environmental problems of the textile and fashion industry. The present study main objectives were to perform an interdisciplinary literature review focused on techniques of reuse and recycling of textiles, mainly cotton fibers, as well as topics related to industrial ecology, the fashion design and eco design. On experimental part it also aimed to carry out tests of microscopy and regain determination of cotton fibers as well as microscopy, tensile and elongation tests in composites made with three different types of thermoset resins (epoxy, polyester orthophthalic and polyurethane) reinforced with textile cotton fibers, configuring possible suggestion for the reduction of textile waste in landfills. For applications such composites were pointed in the fashion sector. It is possible to conclude that the composites made from textile waste could bring benefits to the environment, because besides possessing strength and cohesion functions, they could be assigned to fashion design field from the visual attributes they provide. Thus, they are able to supply specific needs of the consumer market, eager for news, and to furnish the demand for studies of new materials in the textile and fashion sectors, which lacks specific bibliography that bring together aesthetic and technical analysis covering all production phases of materials, processes, creation and design.
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Römhild, Stefanie. "Influence of liquid diffusion on the performance of polymer materials in industrial applications." Licentiate thesis, KTH, Fibre and Polymer Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4433.
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<p>Diffusion of liquids into and through polymers is an important factor that negatively may influence the durability or lifetime of a polymer structure used in industrial applications. In this work two types of polymers, a liquid crystalline polymer (LCP, Vectra A950) and various thermoset resins as used in fibre reinforced plastics (FRP) process equipment were studied with regard to barrier properties, chemical resistance and long-term performance. LCP are known for their outstanding chemical resistance and barrier properties. FRP used in process equipment may be a cost-efficient solution in chemically aggressive environments where standard carbon or stainless steel cannot be used due to its limited corrosion resistance. Transport properties of typical industrial environments were determined for the LCP and the influence of annealing and orientation was investigated to study whether the barrier properties can be improved. The possibility to use LCP as cost-effective lining for FRP was explored. Special focus was put on the diffusion of water and its effect on long-term transport properties and stability of thermoset resins as the performance of FRP is strongly related to the diffusion of water. </p><p>The results showed that Vectra A950 was suitable for organic solvent and non-oxidising acid environments. Its transport properties were gravimetrically determined and found to be 10 to 102 times lower than that of a high barrier fluoropolymer of type FEP. The degree of molecular packing increased with annealing time both below and above the melting point. Below the melting point this was – at least – partly due to crystal formation whereas above the melting point other mechanisms were involved. The effects of annealing and orientation on the transport properties in LCP were, however, very small or not significant and probably significantly longer annealing times are required. LCP has potential to be used as lining material for FRP as the use of an LCP-lining substantially reduced the permeability of and the solute sorption in a bisphenol A epoxy-based vinyl ester resin. The bonding strength was improved significantly by a combined abrasive and oxygen plasma treatment.</p><p>The long-term sorption of water in thermoset resins including bisphenol A epoxy-based vinyl ester, novolac-based vinyl ester, urethane modified vinyl ester and bisphenol A polyester resins was found to increase with exposure time whereas the diffusion coefficient was not significantly affected. It was shown that the presence of water induced relaxation processes that were considered to be the primarily reason for the increase in sorption coefficient in comparison to degradation processes, such as hydrolysis, causing osmotic processes. A general relationship for the estimation of the sorption coefficient at 80ºC in dependence of the water activity and the sorption coefficient at unit activity independent of the resin type was established.</p>
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Baldan, Victor José dos Santos. "Desenvolvimento e caracterização de placas poliméricas produzidas a partir da reciclagem do resíduo industrial de poliuretana termofixa." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/102/102131/tde-30062016-102309/.
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Os compósitos são materiais formados por duas fases de diferentes propriedades químicas e físicas, sendo uma matriz e um reforço, que apresentam alta rigidez, melhores respostas à fadiga sob cargas cíclicas, leveza e resistência mecânica, o que os torna viáveis para substituir materiais nobres e de custo elevado, com diversas aplicações na aeronáutica, nos esportes, na indústria bélica e principalmente na construção civil. Além disso, os compósitos podem ser obtidos a partir da incorporação de resíduos em sua composição, solucionando problemas como o descarte irregular. Com o intuito de contribuir nessa área de conhecimento o presente estudo propôs o desenvolvimento de um compósito em forma de placas poliméricas a partir da incorporação do agregado reciclado de poliuretana termofixa reciclado à resina vegetal de mamona e à mantas de fibra de vidro. Para isso, o trabalho estabeleceu uma metodologia na qual o resíduo industrial de poliuretana termofixa é transformado em agregado reciclado, a partir de processos de corte e moagem, caracterização e classificação segundo as normas NBR 10.004 a 10.007 (ABNT, 2004). Na sequência, com o auxílio de uma prensa térmica, foi possível confeccionar as placas poliméricas e caracterizálas quanto às suas propriedades mecânicas (tração, flexão, punção), físicas (absorção em água, inchamento, densidade e dureza), térmicas (condutividade térmica) e quanto ao seu potencial de durabilidade (resistência ao impacto, à abrasão superficial, ao ataque químico, à exposição ao ultravioleta e às intempéries, resistividade elétrica e flamabilidade). Os resultados obtidos por meio dos ensaios realizados apontaram que os parâmetros ensaiados comportaram-se como materiais semelhantes àqueles utilizados na construção civil, o que possibilita a utilização do material desenvolvido nesta pesquisa em aplicações por este setor.<br>This study proposes the development of a composite material in the form of polymer slabs. The material is created from the incorporation of recycled thermoset polyurethane to castor oil resin and glass fiber mats. Composite materials are formed by two phases with different chemical and physical properties. One phase is a matrix, and the other a reinforcement. These materials are highly stiff, light, have mechanical strength and present better responses to fatigue under cyclic loads. These properties make them a substitute for noble materials, being eligible for uses in aviation, sports, the arms industry and, specially, civil construction. Furthermore, composites may be obtained by the incorporation of residue, solving problems of waste disposal. In the procedures undertaken, the industrial waste of thermoset polyurethane is transformed into a recycled aggregate, achieved by the cutting, grinding, characterization and classification in compliance to the ABNT standards (NBR 10.004 to10.007). Afterwards, with the use of a thermal press, it was possible to produce the slabs and characterize them according to the following properties: mechanical (tensile strength, and puncture), physical (water absorption, swelling and stiffness), thermal (conductivity) and the potential durability (resistance to impact, abrasion, chemical attack. ultraviolet and weather exposure, electrical resistance, and flammability). The test results indicated that the composite behaves similarly to materials used in civil construction, which enables its use in the area.
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Mezzenga, Raffaele. "Hyperbranched polymers as modifiers for thermoset resins /." [S.l.] : [s.n.], 2001. http://library.epfl.ch/theses/?nr=2428.
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Ishii, Yoshiyuki. "Processing of polyphenylene ether with thermoset resins." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301580.
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Glauser, Thierry. "Electron-beam curing of thermoset resins for composites." Doctoral thesis, KTH, Polymer Technology, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2837.
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<p>Electron-beams (EB) are an alternative to traditionalthermal curing when manufacturing thick thermoset composites.It is a quick and energetically efficient technique when curinglarge fiber reinforced parts. Most of the published work onEB-curing deals with curing of thin layers of resin or withcrosslinking of polymers.</p><p>In this thesis, the curing of acrylic resins is studied tohighlight the critical parameters and the particularities ofEB-curing. T<sub>g</sub>of the thermoset increases with increasingirradiation dose and levels-off at T<sub>g∞</sub>, when the resin is fully cured. As inthermal curing, the temperature during cure strongly affectsthe crosslinking of the resin and the thermo-mechanicalproperties of the cured thermoset. Up to T<sub>g∞</sub>, a linear relationship between the maximumtemperature during cure and T<sub>g</sub>was found.</p><p>Carbon and glass fiber composites were EB-cured and tested.Adding fibers to the acrylic resins lowered the exotherm, whichclearly confirmed the importance of temperature during cure tofully crosslink the polymer matrix.</p><p>Comparing EB-, UV- and thermal cure showed that the curingmethod was not the factor that most influenced the propertiesof the cured thermoset. The curing technique imposesconstraints, such as starting temperature and curing time, butit does not influence directly the polymerization and thenetwork formation. These properties are inherent to the monomerused.</p><p>An acrylate resin was blended it with a series of alkyl andmethacrylate functionalized hyperbranched polyester. Thephase-separated thermoset exhibited increased toughness.</p><p><b>Keywords:</b>electron-beam, thermoset, acrylic resin,hyperbranched polyester, thermal effect, toughening</p>
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Claesson, Hans. "Synthesis and Properties of Branched Semi-Crystalline Thermoset Resins." Doctoral thesis, KTH, Fibre and Polymer Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3583.
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<p>This thesis describes the synthesis and characterization ofbranched semi-crystalline polymers. Included in this work isthe SEC characterization of a series of dendrimers. Thebranched semi-crystalline polymers were synthesized in order toinvestigate the concept of their use as powder coatings resins.This concept being that the use of branched semi-crystallinepolymers in a UV-cured powder coating system may offer a lowertemperature alternative thus allowing the use of heat sensitivesubstrates and the added benefit of a reduced viscositycompared to linear polymers.</p><p>A series of branched poly(ε-caprolactone)s (PCL)(degree of polymerization: 5-200) initiated from hydroxylfunctional initiators were synthesized. The final architectureswere controlled by the choice of initiator structure;specifically the dendritic initiators yielded starbranchedPCLs while the linear initiator yielded comb-branchedPCLs. The dendritic initiators utilized were: (1) a3rd-generation Boltorn H-30, commercially availablehyperbranched polyester with approximately 32 hydroxyl groups,(2) a 3rd-generation dendrimer with 24 hydroxyl groups, and (3)a 3rd-generation dendron with 8 hydroxyl groups. Linear PCL wassynthesized for comparison. All dendritic initiators are basedon 2,2- bis(methylol) propionic acid. The comb-branchedpolymers were initiated from a modified peroxide functionalpolyacrylate. The resins were end-capped withmethylmethacrylate in order to produce a cross-linkable system.The polymers and films were characterized using 1H NMR, 13CNMR, SEC, DMTA, DSC, FT-IR, FT-Raman, rheometry and a rheometercoupled to a UV-lamp to measure cure behavior.</p><p>The star-branched PCLs exhibited considerably lowerviscosities than their linear counterparts with the samemolecular weight for the molecular region investigated (2-550kg mol-1). It was also found that the zero shear viscosityincreased roughly exponentially with M.</p><p>The PCL star-branched resins are semi-crystalline and theirmelting points (Tm) range from 34-50°C; films can beformed and cured below 80°C. The viscoelastic behaviourduring the cure showed that the time to reach the gel point, afew seconds, increased linearly with molecular weight. Thecrossover of Gand Gwas used as the gelpoint. Measurement of mechanical properties of films showedthat the low molecular weight polymers were amorphous whilethose with high molecular weight were crystalline after cure.The polymerization of 5,5-dimethyl-1,3-dioxane-2-one (NPC) fromoligo- and multifunctional initiators was evaluated utilizingcoordination and cationic polymerization. Two tin basedcatalysts, stannous(II) 2-ethylhexanoate and stannous(II)trifluoromethane sulfonate, were compared with fumaric acid.Fumaric acid under bulk conditions resulted in lowerpolydispersity and less chance of gelling. The synthesis ofstar-branched polymers was confirmed by SEC data. The starpolymers exhibited a Tg at 20-30°C and a Tm at about100°C.</p><p>All semi-crystalline resins exhibited a fast decrease inviscosity at Tm. Blends of combbranched semi-crystalline resinsand amorphous resins exhibited a transition behavior inbetweenthat of pure semi-crystalline resins and that of amorphousresins.</p><p>The SEC characterization of a series of dendrimers withdifferent cores and terminal groups showed that the core had animpact on the viscosimetric radius of the core while theterminal groups appeared to have no effect.</p><p><b>Keywords:</b>star-branched, semi-crystalline,comb-branched, ring-opening polymerization,poly(ε-caprolactone), dendritic, thermoset, lowtemperature curing, powder coating, UVcuring,poly(5,5-dimethyl-1,3-dioxane-2-one), size exclusionchromatography, rheology, dendritic aliphatic polyester</p>
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Park, In. "Mesostructured silica for the reinforcement of thermoset epoxy polymers." Diss., Connect to online resource - MSU authorized users, 2006.
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Zarrelli, M. "Cure induced property changes and warpage in thermoset resins and composites." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/4675.
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The aim of the present work was to investigate the evolution of thermal and mechanical properties during the polymerisation of a thermosetting resin that is typical those used as the matrix in advanced composites. The mechanism of the cure reaction was studied using differential scanning calorimetry (DSC) in both dynamic (thermal scanning) and isothermal modes, and procedures for correlating the two types of calorimetric data were developed. The model finally chosen encapsulates the diffusion- controlled mechanism of reaction by establishing a one-to-one relationship between the degree of cure and the glass transition temperature, which is assumed to be a structural parameter during the polymerisation. A detailed experimental investigation of specific heat capacity, thermal conductivity, secondary transformations (gelation and vitrification), thermal and chemical volume changes and stress relaxation moduli was carried out to establish a suitable database for the resin. Where possible, a closed analytical model was employed; alternatively, an interpolation procedure was developed evaluate the changes in a selected property during a more complex temperature profile. Experimental equipment was developed to perform shrinkage measurements on the neat resin system; the results obtained were later compared with experimental data from standard liquid dilatometry tests. A simulation of the curing of a bi-material cantilever beam is presented as a test case highlight the influence of property changes on the final curvature. Sample curvature during the experiment was recorded using a digital camera and then analysed using graphical software. The correlation between the observed values of curvature and the results of a finite element based simulation was used to validate the kinetics model and property modelling for the chosen thermosetting resin.
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Grishchuk, S., and J. Karger-Kocsis. "Hybrid thermosets from vinyl ester resin and acrylated epoxidized soybean oil (AESO)." eXPRESS Polymer Letters, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000441.
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Abstract. A series of hybrids composed of styrene crosslinkable vinyl ester (VE) and acrylated epoxidized soybean oil
(AESO) were produced via free radical-induced crosslinking. The VE/AESO ratio was changed between 75/25 and 25/75 wt%. Moreover, to support phase grafting the VE/AESO = 50/50 wt% hybrid was modified with phthalic anhydride in various amounts (1, 5 and 10 wt%). The structure of the hybrid systems was investigated by dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), and atomic force microscopy (AFM). The properties of the systems were assessed by static flexural and fracture mechanical tests. The resistance to thermal degradation was inspected by
thermogravimetric analysis (TGA). The results suggested that the hybrids have an interpenetrating network (IPN) structure.
With increasing AESO content the stiffness (modulus), strength and glass transition temperature (Tg) of the hybrids
decreased, whereas their ductility increased. Phthalic anhydride caused an adverse trend. Both the fracture toughness and fracture energy increased with increasing AESO content. They were less affected by adding phthalic anhydride phase couplant.
Interestingly, the hybrids outperformed the parent VE and AESO in respect to resistance to thermal degradation.
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Corvo, Alguacil Marina. "Substitution of thermosets by thermoplastic resins in electrical insulation applications." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-66557.
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Höer, Martin. "Einfluss der Material- und Verarbeitungseigenschaften von Phenolharzformmassen auf die Qualität spritzgegossener Bauteile." Doctoral thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-155078.
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Spritzgießbare Duroplaste zeichnen sich durch hohe thermo-mechanische Beständigkeit, geringe Schwindung und niedrige Materialkosten aus. Damit können die Anforderungen an spritzgegossene Präzisionsbauteile für den Automobilbau erreicht werden. Im Rahmen der vorliegenden Arbeit werden unterschiedliche Novolak-Phenolformmassen hinsichtlich ihres hygroskopischen Verhaltens und dessen Auswirkung auf die Spritzgießverarbeitung und die Bauteilqualität untersucht. Das Absorptionsverhalten kann mithilfe der Fick’schen Diffusionsgesetzte näherungsweise beschrieben werden. Auf Basis von mechanischen Untersuchungen sowie der Beurteilung der Maßhaltigkeit eines Präzisionsdemonstrators hinsichtlich Schwindung und Verzug wird zudem der Einfluss der Prozessparameter beim Spritzgießen bestimmt. Die vorgestellten Untersuchungen zeigen die Grenzen der Verarbeitung und der realisierbaren Bauteilqualität auf, die auf die großserientaugliche Verarbeitung von duroplastischen Bauteilen übertragen werden können<br>Injection moldable thermosetting materials show excellent material properties, e.g. high thermo-mechanical resistance and reduced shrinkage in combination with low material cost. Thus, technical requirements for high performance parts for automotive applications can be achieved. In the scope of this work different phenolic novolac compounds were investigated regarding their hygroscopic behavior with its influence for injection molding and product quality. The absorption can be approximately described by Fick’s-Diffusion-Model. The interrelationship of injection molding parameters and the thermo-mechanical behavior is examined on the basis of mechanical testing and the assessment of the dimensional accuracy for a thermoset high precision part. The presented investigations point to the limit of processing and realizable part quality which can be transferred for high performance parts molded in mass production
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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.<br>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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Raschke, Kristin. "Grundlagenuntersuchungen zur Prozess- und Struktursimulation von Phenolharzformmassen mit Kurz- und Langglasfaserverstärkung." Doctoral thesis, Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-229327.
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Thermisch und mechanisch hoch beanspruchte Bauteile im Automobil erfordern den Einsatz hochbeständiger Werkstoffe, bei gleichzeitig niedrigen Materialkosten und effizienter Verarbeitung. Rieselfähige Phenolharzformmassen zeichnen dabei eine Werkstoffklasse aus, die aufgrund ihres Eigenschaftsprofils neue Anwendungsbereiche für einen polymeren Werkstoffeinsatz ermöglichen können. Im Rahmen der vorliegenden Arbeit werden im Hinblick auf eine Bauteilentwicklung mithilfe der integrativen Simulation die Grundlagen einer ganzheitlichen Simulationskette der Prozess- und Struktursimulation von rieselfähigen Phenolharzen mit Kurz- und Langglasfaserverstärkung erarbeitet. Das auf Basis umfangreicher Prozessuntersuchungen abgeleitete Strömungsverhalten kann mithilfe des Block-/Scherströmungsmodells beschrieben werden. Die Ergebnisse der Mikrostrukturanalyse zeigen jedoch eine Orientierungsdynamik der Fasern, welche zum gegenwärtigen Zeitpunkt mithilfe der empirischen Modelle der klassischen Spritzgießsolver nicht abgebildet werden kann. Die mikromechanische Materialmodellierung erfolgt entsprechend an der experimentell ermittelten Mikrostruktur, welche die Berücksichtigung von Faserbündelungen und -krümmungen in der mechanischen Strukturanalyse erlaubt. Das abgeleitete elastoplastische Materialmodell wird zur Vorhersage des Ermüdungsverhaltens unter harmonischer und nichtharmonischer Schwingbeanspruchung um ein zyklisches Versagensmodell erweitert, welches eine mittellast- und temperaturunabhängige Berechnung unter Berücksichtigung der Anisotropie ermöglicht. Die Validierung der statischen und schwingenden Beanspruchung erfolgt an einer einfachen Probestabgeometrie sowie einem Strukturbauteil, einem PKW-Motorträger<br>Thermally and mechanically highly stressed automotive components require the use of highly resistant materials, with low material costs and efficient processing. Phenolic resin molding compounds represent a class of materials, which can open up new applications for a polymeric material use due to their property profile. In the present work, the fundamentals of a simulation chain of fluid mechanical and structural simulation of phenolic resins with short and long glass fiber reinforcement are developed, with a view to component development using integrative simulation. Based on extensive process investigations the derived flow behavior can be described using the block/ shear flow model. However, the results of microstructure analysis show a dynamic of fiber orientation, which can not be predicted at the present time using the empirical models of classical injection molding simulation. Accordingly, the micromechanical modeling is carried out at the experimentally determined microstructure. That allows the inclusion of fiber bundling and bending in the mechanical structure analysis. The derived elastoplastic material model is extended by a fatigue failure model to predict the fatigue behavior under harmonic and non-harmonic cyclic stress which allows a calculation taking into account the anisotropy, the stress ratio and the temperature. The validation of the static stress and fatigue is performed both on a simple test bar geometry and a structural component, an automotive engine bracket
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Cho, Hosouk. "Chemical incorporation of polyhedral oligomeric silsesquioxane into thermoset matrices." Diss., Mississippi State : Mississippi State University, 2006. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.
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Flores, Guillén Marjorie Yusneiry. "Toughness improvement of epoxy thermosets by adding dendritic structures." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/128206.
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Las resinas epoxi se encuentran entre los materiales termoestables más importantes utilizados en un gran abanico de aplicaciones tales como adhesivos, matrices para materiales compuestos, recubrimientos de superficies y encapsulamiento de componentes electrónicos. La principal razón de su amplio uso es la buena combinación entre resistencia a la tracción y a la corrosión, rigidez y buenas propiedades eléctricas. Sin embargo, debido a su elevado grado de entrecruzamiento, las resinas epoxi tienen una baja resistencia al impacto, la cual limita su uso en algunas aplicaciones específicas. Para contrarrestar este efecto, a las resinas epoxi se les añaden distintos modificantes entre los que se pueden destacar los polímeros hiperramificados.
En esta tesis doctoral se plantea estudiar el efecto de la incorporación de distintos modificantes poliméricos a resinas epoxi convencionales glicidílicas y cicloalifáticas en el proceso de curado y en las características del material final. Estos agentes modificantes tienen estructuras dendríticas y son polímeros hiperramificados y estrellas. Unos son derivados de los poliésteres comerciales Boltorn® y otros con estructuras hiperramificadas de poliéter o poliéster, previamente sintetizadas y en algunos de los casos modificados en los grupos finales con estructuras alifáticas.
Respecto a los sistemas de curado utilizados han sido diferentes los agentes seleccionados. En primer lugar se estudiaron los diisocianatos catalizados por aminas, sustituyéndose estos catalizadores por triflato de iterbio. El mecanismo de reacción en ambos casos fue estudiado por FTIR y mediante calorimetría pudiéndose determinar las reacciones que tenían lugar y cuantificar la proporción de grupos funcionales presentes en la red. También se estudiaron
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otros agentes como son los anhídridos en presencia de amina terciaria, o los triflatos de lantánido, iniciadores catiónicos. Los sistemas anteriormente citados actúan térmicamente. De forma alternativa se han estudiados sistemas fotoiniciados catiónicos. Finalmente, se ha estudiado un nuevo sistema en dos etapas que se basa en una reacción tipo click (tiol-eno), que tiene lugar fotoquímicamente, y que en presencia de fotoiniciadores catiónicos, genera sales de sulfonio que son iniciadores catiónicos.
Esta Tesis Doctoral está estructurada en diferentes capítulos de la siguiente forma:
Capítulo 1:
Incluye una breve descripción del marco teórico relacionado con los materiales termoestables, así como también un breve resumen de lo reportado actualmente en el campo de los agentes modificantes dendríticos poliméricos, procesos de curado y agentes de curado, teniendo un enfoque particular sobre la mejora de las propiedades de los materiales epoxídicos termoestables. Además, en este capítulo se incluye la descripción del objetivo general y los objetivos específicos de esta Tesis Doctoral.
Capítulo 2:
Corresponde a la parte experimental donde se describen los instrumentos y técnicas utilizadas para la realización de este trabajo.
Capítulos 3 y 4:
Se muestra como en la formación de redes de oxazolidonas¿isocianuratos-éteres, el factor determinante para controlar la cantidad de cada fracción, es la relación entre isocianato y grupos epoxi presentes en las
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formulaciones. Asimismo, la selección del catalizador, base o ácido de Lewis, también modifica la estructura de la red y las propiedades termomecánicas de los materiales termoestables.
Capítulos 5:
Se modifican los grupos hidroxilo finales de hiperramificados tipo Boltorn® con cadenas alifáticas y grupos finales vinílicos o epoxídicos, que se adicionan a formulaciones epoxi/isocianato/amina terciaria. Se estudia el proceso de curado y las características termomecánicas. Se hace especial hincapié en la morfología de los materiales, estudiada por SEM.
Capítulos 6 y 7:
Se modifican los grupos hidroxilo finales de hiperramificados tipo Boltorn® con cadenas de 10-undecenoilo en diferentes proporciones y se adicionan estos modificantes en formulaciones de DGEBA/anhídrido/amina terciaria. Se estudia tanto el proceso de curado como las propiedades del material final. Los valores de resistencia al impacto se relacionan con la morfología observada por microscopia electrónica.
Capítulo 8:
Se introducen como agentes modificantes polímeros hiperramificados con distintos grados de modificación obtenidos por la acilación del poliglicidol y se estudia el efecto que ejercen éstos sobre las distintas propiedades termomécanicas de los materiales termoestables en función del grado de modificación y su compatibilidad con la matriz epoxidica.
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Capítulos 9 y 10:
Muestran la incorporación de polímeros hiperramificados de tipo estrella sintetizadas a partir de núcleos tipo Boltorn de diferente peso molecular y brazos de poli(¿-caprolactona) en formulaciones de epoxi cicloalifática. En el primero de estos capítulos el curado se efectúa en condiciones térmicas utilizando triflato de iterbio como iniciador, mientras que en el segundo se efectúa un fotocurado iniciado por una sal de sulfonio como fotoiniciador.
Capítulo 11:
En este capítulo se propone un nuevo sistema de curado dual en dos etapas que consta de una reacción tiol-eno, que tiene lugar bajo irradiación seguida por un curado térmico de resina epoxi cicloalfática. Esta segunda etapa tiene lugar a temperaturas superiores a los 100ºC y viene iniciada por las sales de sulfonio producidas en la primera etapa a partir de los tioéteres formados y su activación mediante fotoiniciación. La adición de polímeros hiperramificados con terminaciones alílicas, activas en la reacción tiol-eno, permite obtener materiales con altas Tgs, a pesar de la flexibilidad introducida en la red por el tritiol utilizado. El sistema de curado propuesto tiene características latentes con un curado en dos etapas dual fotoquímico-térmico.
La tesis recoge al final las principales conclusiones alcanzadas así como una breve lista con las contribuciones científicas relacionadas con esta tesis doctoral.
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Lee, Yong-Joon. "Structure-property behavior of novel high performance thermoplastic and thermoset structural adhesives and composite matrix resins." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-162715/.
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HILAIRE, BRUNO. "Etude du vieillissement thermique d'une resine polyimide thermos table : l'ip 960." Paris, ENSAM, 1991. http://www.theses.fr/1991ENAM0006.
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Cette etude necessite une connaissance minimale de l'etat structural du reseau a l'issue de la mise en uvre. Les techniques utilisees (irft, dsc, chromatographie d'exclusion sterique) combinees a l'emploi de composes modeles mono et difonctionnels, ont permis d'aborder les modifications structurales precedant la reticulation et d'apporter des elements en faveur d'un des mecanismes de reticulation proposes dans la litterature. Apres une etude bibliographique, nous presentons les resultats du vieillissement thermique dans l'air entre 250c et 360c. Apres avoir identifie les principaux parametres, (temperature, geometrie, morphologie), nous avons clairement mis en evidence que la thermostabilite des polynadimides a l'etat liee a la presence (ou non) d'eau lors des premieres etapes. L'etude sous vide a 360c fait apparaitre une cinetique de degradation plus complexe, l'aniline etant le produit de degradation majoritaire. Nous tentons de relier structure du reseau et vieillissement thermique en proposant des mecanismes de degradation: sont d'abord evoques les processus thermolytiques qui conduisent a la formation d'amines primaires et de noyaux aromatiques mono substitues; puis ensuite les mecanismes d'oxydation (attaque du pont methylene du ddm et d'un ch tertiaire au voisinage de l'imide). Enfin nous apportons des donnees manquantes sur l'hydrophilie de ces materiaux. Nous avons caracterise les variations de concentration d'eau a l'equilibre et de diffusivite en fonction de la temperature et de l'hygrometrie
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Adekunle, Kayode. "Bio-based Composites from Soybean Oil Thermosets and Natural Fibers." Doctoral thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3587.
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In order to reduce over-dependency on fossil fuels and to create an environment that is free of non-degradable plastics, and most importantly to reduce greenhouse gas emission, bio-based products are being developed from renewable resources through intense research to substitute conventional petrochemical-based plastics with renewable alternatives and to replace synthetic fibers with natural fibers. Many authors have done quite a lot of work on synthesizing polymers from renewable origin. Polylactic acid (PLA) has been developed and characterized, and it was found that it has enormous potential and can serve as an alternative to conventional thermoplastics in many applications. Modification of the plant oil triglycerides has been discussed by many authors, and research is still going on in this area. The challenge is how to make these renewable polymers more competitive in the market, and if possible to make them 100% bio-based. There is also a major disadvantage to using a bio-based polymer from plant oils because of the high viscosity, which makes impregnation of fibers difficult. Although natural fibers are hydrophilic in nature, the problem of compatibility with the hydrophobic matrix must be solved; however, the viscosity of the bio-based resin from plant oils will complicate the situation even more. This is why many authors have reported blending of the renewable thermoset resin with styrene. In the process of solving one problem, i.e reducing the viscosity of the renewable thermoset resin by blending with reactive diluents such as styrene, another problem which we intended to solve at the initial stage is invariably being created by using a volatile organic solvent like styrene. The solution to this cycle of problems is to synthesize a thermoset resin from plant oils which will have lower viscosity, and at the same time have higher levels of functionality. This will increase the crosslinking density, and they can be cured at room temperature or relatively low temperature. In view of the above considerations, the work included in this thesis has provided a reasonable solution to the compounded problems highlighted above. Three types of bio-based thermoset resins were synthesized and characterized using NMR, DSC, TGA, and FT-IR, and their processability was studied. The three resins were subsequently reinforced with natural fibers (woven and non-woven), glass fibers, and Lyocell fiber and the resulting natural fiber composites were characterized by mechanical, dynamic mechanical, impact, and SEM analyses. These composites can be used extensively in the automotive industry, particularly for the interior components, and also in the construction and furniture industries. Methacrylated soybean oil (MSO), methacrylic anhydride-modified soybean oil (MMSO), and acetic anhydride-modified soybean oil (AMSO) were found to be suitable for manufacture of composites because of their lower viscosity. The MMSO and MSO resins were found to be promising materials because composites manufactured by using them as a matrix showed very good mechanical properties. The MMSO resin can completely wet a fiber without the addition of styrene. It has the highest number of methacrylates per triglyceride and high crosslink density.<br>Akademisk avhandling för avläggande av teknologie doktorsexamen vid Chalmers Tekniska högskola försvaras vid offentlig disputation, den 6:e maj, Chalmers, KE-salen, Kemigården 4, Göteborg, kl. 10.00.
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Pavlík, Ondřej. "Návrh kompozitní objímky rotoru vysokootáčkového rotačního stroje." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382567.
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The diploma thesis focuses on manufacturing carbon fiber and epoxy composite material using filament winding method. Material properties of manufactured composite are ap-proximated using analytical and numerical homogenization models. Calculated material properties are applied to design and evaluate reserve factor of retaining sleeve for high speed brushless permanent magnet synchronous motor. Margin of safety of designed rotor is evaluated using composite failure criteria. Test stand for both static and dynamic testing is designed, static test stand is manufactured and assembled. Static strength test is carried out.
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Savonnet, Etienne. "Development of bio-based epoxy thermosets for aerospace launchers." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0022.
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La grande majorité des résines époxy utilisées aujourd’hui sont issues ou dérivées du bisphénol-A (BPA). Cependant, le BPA est soumis à de très fortes régulations, notamment vis-à-vis de sa récente classification comme substance chimique extrêmement préoccupante par l’agence européenne des produits chimiques (ECHA). Dans un but d’anticiper les évolutions de régulation, ArianeGroup a décidé de remplacer cette substance chimique de ces formulations. Ces travaux de thèse portent donc sur l’élaboration de nouvelles résines époxy biosourcées ayant des propriétés similaires voire supérieures aux références dérivées du bisphénol-A. Pour cela, une bioplatforme de monomères polyépoxydés issus de la vanilline, du méthyl vanillate, du 2,6-diméthoxyphénol et de l’eugénol a été développée. Ces précurseurs biosourcés ont ensuite été utilisés comme précurseurs de réseaux époxyde par réticulation avec des amines. Les réseaux réticulés biosourcés ainsi obtenus ont démontré des propriétés thermomécaniques remarquables bien supérieures à la référence de type DGEBA, notamment en termes de température de transition vitreuse (>300 °C) et taux de coke (>50%). En parallèle de ces travaux, la synthèse de diamines biosourcées, dérivées de la divanilline, et pouvant être utilisées comme agents de réticulation de résines époxy, a été réalisée. Des réseaux époxyde entièrement biosourcés ont ainsi été synthétisés et présentent des propriétés thermomécaniques prometteuses<br>Today, most of the epoxy resins produced are derived from bisphenol-A (BPA). However, BPA is subject to strong regulations, particularly because of its recent classification as chemical of very high concern by the European Chemicals Agency (ECHA). In order to anticipate new regulations, ArianeGroup has decided to replace this substance in its applications. The aim of this thesis is to develop new bio-based epoxy thermosets with comparable thermomechanical properties as the ones issued from bisphenol-A-based materials. For this purpose, a bio-platform of epoxy monomers from vanillin, methyl vanillate, 2,6-dimethoxyphenol and eugenol was developed. These precursors were cross-linked with amines used as curing agent to obtain bio-based epoxy networks. The latter demonstrated thermomechanical properties well above the DGEBA-type reference, especially in terms of glass transition temperature (> 300 °C) and char content (> 50%). Finally, the synthesis of bio-based diamines derived from divanillin was developed and enabled the synthesis of fully bio-based epoxy networks with promising thermomechanical properties
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Hardrict, Shauntrece Nicole. "Novel Novolac-Phthalonitrile and Siloxane-Phthalonitrile Resins cured with low melting Novolac Oligomers for Flame Retardant Structural Thermosets." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9669.
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The chemical modification of low molecular weight novolac oligomers and siloxane/silane-containing monomers has led to novel phthalonitrile derivatives with low glass transition temperatures, ranging from -25 to 75 ºC. Multi-functional, low molecular weight phenol-formaldehyde novolac resins were blended with these novel phthalonitrile derivatives to achieve low viscosity resin blends. Moderate temperatures and rapid curing cycles were employed (200 ºC, 1 h and 225 ºC, 4h) to produce networks with high glass transition temperatures (> 250 ºC). A decrease in the sharp band at 2230 cm⁻¹, attributed to the nitrile functionality of the phthalonitrile resin, was monitored in FTIR studies and indicated the progress of the reactions. Ninety percent conversion was achieved within ~ 30 min.
Thermal analysis of siloxane-phthalonitrile/novolac networks cured for 1h at 200 ºC and 4h at 225 ºC did not exhibit glass transition temperatures below 250 ºC. In dynamic TGA studies, 5% weight loss temperatures up to 418 ºC were observed, and the materials exhibited 50 to 56 % char at 800 ºC in nitrogen. Networks prepared from a resin blend containing 50 weight% of a phthalonitrile derivative of a 260 g mol⁻¹ novolac oligomer, 50 weight% of the 260 g mol⁻¹ novolac oligomer, and 1.5 mol % triphenylphosphine (based on novolac) (NOV/NOV/TPP) cured at 200 ºC for 1h, did not exhibit a Tg below 250 ºC via DSC. These networks exhibited a 5% weight loss temperature of 350 ºC, and 70 % char at 800 ºC in TGA studies under nitrogen. This degree of char formation makes these materials appealing for use in carbon-carbon composites. Post-curing these networks at 200 ºC for 1h, and then at 225 ºC for 4h, resulted in high thermo-oxidative stability, with a 5% weight loss observed at 447 ºC and 50 % char at 800 ºC.
Blending tetramethyldisiloxane phthalonitrile monomers with 260 g mol⁻¹ novolac oligomers afforded prepolymer resins with low melt viscosities, 560 mPa s at 80 ºC. Such viscosities may allow these resins to be processed via vacuum assisted resin transfer molding (VARTM) at low temperatures and heated at elevated temperatures to produce flame resistant three-dimensional networks.<br>Master of Science
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Stemmelen, Mylène. "De la fonctionnalisation d'une huile végétale aux matériaux polymères bio-sources : étude de lipopolymères en solution et de résines epoxy lipidiques." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20077.
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Ce travail de thèse examine trois voies de valorisation de l'huile de pépins de raisin au travers de l'élaboration de matériaux polymères auto-associatifs, réticulés ou hybrides. L'huile végétale ou un modèle lipidique (l'oléate de méthyle) sont d'abord fonctionnalisés grâce à leurs insaturations menant à des huiles hydroxylées, aminées, ou phosphorées.Dans une première étude, l'huile et l'oléate de méthyle ont été hydroxylés par réaction thiol-ène. Les alcools gras sont ensuite transformés en macroamorceurs capables d'amorcer la polymérisation cationique par ouverture de cycle de la 2-méthyl-2-oxazoline. Les lipopolymères (LipoPOx) amphiphiles ainsi synthétisés sont capables de s'auto-associer et de former des nanoparticules monodisperses observées par DLS. Dans une deuxième étude, l'huile et certains de ses dérivés amide ont été modifiés sous UV par addition radicalaire du chlorure de cystéamine, conduisant à une diamine linéaire et à une polyamine ramifiée. Ces dernières ont été utilisées comme durcisseurs d'huile époxydée permettant la réticulation de résines époxy à fort taux de carbone biogénique. L'étude thermomécanique par analyse rhéologique montre que ces matériaux thermodurcissables ont des Tg comprises entre -38 et -9°C.Dans une troisième étude, les lipides ont été fonctionnalisés par addition radicalaire de diméthylphosphite par voie photochimique ou thermique. La transformation ultérieure des esters phosphonés en fonctions silylées a rendu ces composés réactifs vis-à-vis du titane et de ses oxydes. L'ancrage de lipides sur des particules de TiO2 ou des feuilles de Titane influe sur leurs propriétés de surface<br>This Ph-D work deals with the valorization of grapeseed oil for the preparation of novel and various bio-based polymers. Three pathways are developed starting from lipids and leading to polymeric materials such as self-assembled polymers, thermosets and hybride polymers. First, the vegetable oil and methyloleate were modified using radical addition on their double bonds. Following, hydroxylated, aminated and phosphonated lipids were synthesized.In a first study, the oil was hydroxylated via thiol-ene coupling reaction. The fatty alcohol was then converted into initiator for the cationic ring-opening polymerization of 2-methyl-2-oxazoline. These Lipopolymers so-called LipoPOx exhibit hydrophilic POx block and fatty block. Their amphiphilic nature confer them a self-organization ability in water. A monomodal and narrow distribution of nanoparticles was observed by DLS and AFM.In a second study, the oil and some fatty amides were also functionalized by UV-induced radical addition using cysteamine hydrochloride. A linear diamine and a branched polyamine were synthesized and used as hardeners of epoxidized vegetable oil leading to thermosets with high level of bio-carbone. The investigation on thermo-mechanical properties showed a Tg between -38 and -9°C.In a last study, the lipids were modified by radical addition of dimethylphosphite using thermal or photochemical process. Then, the phosphonate esters were converted into silylated moieties making them reactive toward titanium. The anchoring of lipids onto titanium based materials induced a modification of their surface properties
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Motillon, Coralie. "Formulation et caractérisation de résines thermodurcissables bio-sourcées pour l’industrie du bois." Thesis, Pau, 2013. http://www.theses.fr/2013PAUU3036/document.
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Les travaux présentés dans ce manuscrit sont consacrés à l’étude et à l’élaboration de résines de collage bio-sourcées pour remplacer les résines Urée-Formol (UF) d’origine pétrochimique, sources de formaldéhyde, utilisées actuellement dans l’industrie panneautière. Les résines étudiées dans le cadre de cette thèse sont formulées à partir de ressources locales (dextrines issues d’amidon de maïs et tanins d’écorces de pin maritime) et doivent respecter certaines contraintes industrielles. Pour répondre à ces contraintes, les travaux de recherche présentés dans ce mémoire vont de la compréhension structurale des mélanges des produits de base jusqu’à la fabrication de panneaux à l’échelle du laboratoire, en passant par la formulation et la réticulation des différentes résines thermodurcissables. Ces travaux montrent qu’il est nécessaire de travailler en milieu alcalin pour solubiliser les tanins. Dans cette situation, les mélanges tanins/dextrines donnent des suspensions colloïdales. Les fractions massiques en tanins et en dextrines permettant d’obtenir des paramètres respectant le cahier des charges varient de 0 à 40%. La réticulation de ces mélanges par l’épichlorhydrine a permis l’obtention de colles thermodurcissables insolubles dans l’eau ayant une bonne stabilité dimensionnelle à sec, mais un pouvoir gonflant plus ou moins important selon la formulation. Les propriétés adhésives, mécaniques et thermiques de ces matériaux ont été caractérisées et ont permis de sélectionner des formulations de colles ayant les meilleures performances thermomécaniques. Enfin, tout en respectant un protocole industriel, des composites ont été fabriqués à partir de ces colles et des particules de bois. Il a été montré que les panneaux de particules obtenus ont des performances mécaniques équivalentes à ceux fabriqués avec des colles UF<br>This work aims to substitute resins based on formaldehyde as UF by “green” thermosetting adhesives based on natural and renewable local products, in the wood composite industry. The resins studied in this thesis are made from local resources (dextrins from corn starch and tannins from maritime pine barks) and must respect certain industrial requirements. To meet these industrial constraints, the research work of this manuscript deals with studies ranging from the structural understanding of basic product mixtures, up to the characterization of the properties of panels manufactured in the lab, including the formulation and reticulation of resins. These studies show that it is necessary to work in an alkaline medium to solubilize the tannins. In this situation, the tannins / dextrin mixtures give colloidal suspensions. The mass fractions in tannins and dextrins allowing to obtain parameters respecting the specifications vary from 0 to 40%. The epichlorohydrin has been used as hardener to cross-link these resins. Thermosetting materials with good dimensional stability have been obtained. However the resin swelling depends on the composition of the formulation. Adhesive, mechanical and thermal properties of these materials were characterized. Thus, adhesive formulations with the best thermomechanical performances have been selected. Finally, composites have been made from these adhesives and wood particles, respecting an industrial procedure. It has been shown that these panels and those obtained with UF adhesives have equivalent mechanical performances
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Matoušová, Klára. "Dielektrické vlastnosti epoxidových pryskyřic." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-402126.
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This diploma thesis deals with the fundamental properties of epoxide mixtures, as determining of these fundamental properties of epoxide mixtures could in the case of favorable results lead to diminishing the amount of defects in epoxide-embedded instrument transformers. As the influence of effects in the manufacturing process of transformers causing poor quality is very extensit, the biggest emphasis is laid capitally on the influence of the epoxide casting mixture composition. The thesis describes the manufacture technology including used methodics and materials. The compositions of epoxide resins and the mechanisms of their curing. Also, the definitions of fundamental properties of dielectric materials and the description of diagnostic methods used to relative permitivity, dissipation factor and inner resistivity are included. suitable casts of acquired samples were set and dried out within the experimental part, followed by measurement of fundamental electrical properties in temperature and frequency relations. Hereafter a comparison of individual samples and the evaluation of their electrical properties will be carried out.
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Horák, Luděk. "Analýza elektrických vlastností epoxidových pryskyřic s různými plnivy v teplotní a kmitočtové závislosti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-376991.
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Presented master's thesis is focused on studying electroinsulating epoxy resin-based sealings. It describes the chemical composition, production, properties and measuring methods of basic electric quantities of these materials. The aim of the thesis is to compare several sets of samples of composite epoxy resins with different kinds of micro-ground siliceous sand as a filling. The temperature and frequency dependence of relative permittivity, dissipation factor and inner resistivity are measured for given samples.
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Scheffler, Thomas. "Werkstoffeinflüsse auf den Spritzgussprozess von hochgefüllten Phenol-Formaldehydharz-Formmassen." Universitätsverlag Chemnitz, 2018. https://monarch.qucosa.de/id/qucosa%3A32200.
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Im Rahmen der vorliegenden Arbeit wurden verschiedene duroplastische Formmassen laboranalytisch hinsichtlich der rheologischen und thermischen Eigenschaften untersucht. Es wurde u.a. gezielt die absolute Materialfeuchte gesteigert, um den Einfluss dieser auf das Fließ Härtungsverhalten zu charakterisieren. Anschließend wurden die Materialien auf einer hochinstrumentierten Spritzgussmaschine mit einem Fließspiralenwerkzeug untersucht. Dabei konnte ein direkter Zusammenhang zwischen dem Rückfluss und dem Plastifizierdrehmoment in Abhängigkeit der Materialfeuchte und der Prozessparameter detektiert werden . Des Weiteren wurden über die Differenzdruckmessung im Fließspiralenwerkzeug die scheinbaren Viskositäten über den Fließweg ermittelt. Hierbei konnten unterschiedliche Aufschmelzeffekte über die Fließweglänge in Abhängigke it der duroplastischen Formmasse, der absoluten Materialfeuchte und der Prozessparameter detektiert werden . Durch Schererwärmung konnte die Formmassentemperatur teilweise die Werkzeugtemperatur übersteigen. Hinsichtlich der mechanischen Eigenschaften (Schlagzähigkeit, Biegefestigkeit) konnten keine signifikanten Einflussgrößen detektiert werden. Hinsichtlich des Tg konnten systematischen Unterschiede detektiert und begründet werden. Die beste Möglichkeit zur Ermittlung des Tg lieferte die TMA. Die thermischen Glasübergänge korrelieren mit den in der DSC ermittelten Aushärtegraden , wobei mit steigender Materialfeuchte ein geringer Aushärtegrad detektiert wird.<br>Within this paper, the rheologieal and thermie eharaeteristies of different thermosetting molding eompounds were investigated using lab analysis methods. Among others, the absolute moisture eontent was inereased purposefully to investigate its influenee on the flow-euring behavior. Subsequently, the materials were analyzed using a highly instrumented injeetion-molding maehine and a flow spiral tool. A direet link between the baekflow and the plastifieation torque dependent on the moisture eontent and proeess parameters was deteeted . Furthermore, a measurement of the differential pressure was eondueted within the flow spiral to deteet the apparent viseosity over the flow path. Within this proeess, different melting effeets over the flow eurve length depending on the molding eompound, the absolute moisture eontent and proeess parameters were deteeted. The shear heating lead to a material temperature inerease of the molding eompound, whieh was partly higher than the tool temperature . Coneerning the meehanieal eharaeteristies (impaet strength, flexural strength), no signifieant influeneing faetors eould be deteeted. In eontrast, systematie differenees of the glass transition temperature were deteeted and their eause eould be explained. The best way to determine the glass transition is the TMA. The glass transition temperatures eorrelate with the degree of eure determined with the DSC, whereas an inereasing moisture eontent is assoeiated with a lower degree of eure.
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Derose, Anthony Nickolas. "Modeling resin flow during compression of copper-clad thermoset composite laminates." 1999. http://catalog.hathitrust.org/api/volumes/oclc/42004166.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1999.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 55-57).
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Cruz, Javier C. "Advanced cure monitoring and analysis for optimization of thermoset resin processes." 2008. http://www.library.wisc.edu/databases/connect/dissertations.html.
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Tsai, Jui-Che, and 蔡瑞哲. "Preparation and Properties of Silicon–Containing Thermoset Polyphenylene Ether Resin Compositions." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/13872662071520512661.
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碩士<br>國立高雄應用科技大學<br>化學工程系碩士班<br>95<br>Communication devices tend to function at higher speeds and frequencies. The substrate material for such devices demands a high glass transition temperature (Tg), low dielectric constant (Dk), and low loss factor (Df). Polyphenylene oxide (PPO), having high Tg and superior electrical properties, is a potential material for high frequency substrates. However, PPO is a thermoplastic resin and is poor in solvent resistance. Therefore, there is a need to modify PPO into a thermosetting resin so as to increase the solvent resistance and heat resistance properties. Recently, organophosphorous compounds have been considered to replace the traditional brominated flame retardants, with the consideration of avoiding the generation of corrosive and toxic gas. However, phosphorous-containing flame retardants may release the toxic “environmental hormone” under fire.
The goal of this research is focused on the preparation of silicon-containing polyphenylene oxide-thermosetting resin composition, which can be used in preparing prepregs and copper-clad laminates for high frequency printed circuit boards. Low molecular weight polyphenylene oxides (LPPO) can be synthesized by the oxidatively coupling a bifunctional phenol and a monofunctional phenol compound in the presence of cupric chloride and an amine. The structure of synthesized LPPOs will be confirmed by Fourier transform infrared spectroscopy (FTIR), Gel-Permeation Chromatography (GPC), nuclear magnetic resonance spectroscopy (NMR). Multifunctional epoxy resins will be introduced to the LPPOs and then cured with cyanate ester (BADCy) and amine terminated polydimethyl siloxane (ATPDMS), respectively. The properties of cured epoxy resins will be studied by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal mechanical analysis (TMA), dielectric analysis (DEA), thermal gravimetric analysis (TGA), limiting oxygen index (LOI), UL-94 vertical test and moisture absorption. The dielectric constant and moisture absorption of resulting cured polyphenylene oxide-thermosetting resins decreased with the increasing of LPPO contents. As a result of forming the carbon-silicon residue, the thermal stability and flame-retardant properties of cured silicon-containing polyphenylene oxide-thermosetting resins increased with the increasing of silicon contents. UL-94 V-1 rating could be achieved with 50 phr LPPO and silicon content as low as 2% in cured silicon-containing polyphenylene oxide-thermosetting resin. The LOI value of cured silicon-containing polyphenylene oxide-thermosetting resin with 100 phr of LPPO and 3% silicon content was 33 and UL-94 V-0 rating could be achieved. The cured materials prepared therefrom will be highly solder resistant, solvent resistant, flame retardant and also have excellent dielectric properties. The use of this resin composition will be environmentally friendly.
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Castellà, Núria [Verfasser]. "Development and characterization of polyurea-based thermoset resins / von Núria Castellà." 2009. http://d-nb.info/994151365/34.
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Chen, Yu-Jane, and 陳育甄. "Synthesis and characterization of the thermoset maleimide-epoxy and bismaleimide resins." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/86207682028880630165.
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碩士<br>中原大學<br>化學工程研究所<br>91<br>英文摘要
A novel compound (4-maleimidophenylglycidylether, MIE) containing both maleimido and epoxide groups was synthesized as use as monomers for preparation of new thermosetting resins. The chemical structure of MIE was characterized with FTIR and 1H NMR. Thermosetting resins showing high glass transition temperatures (>210
℃), good thermal stability (higher than 350 ℃), and excellent flame retardance (LOI = 38) were obtained from curing MIE with conventional
epoxy curing agents of DDM and DICY. The kinetics of the curing reactions was also studied.
Reacting MIE with various biphenol compounds gave a convenient approach to prepare bismaleimide compounds having epoxy linkages between the maleimide groups. These bismaleimides exhibited good organosolubility, low melting points, and wide processing windows, consequently referred their good processibility. It was found that
incorporating silicon group into the bismaleimide resulted in superior thermal stability of the cured bismaleimides.
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Tsai, Kun-Ling, and 蔡昆霖. "Synthesis of phosphorus-containing multifunctional epoxy resin and thermal properties of the resulting thermosets." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/94863378360763921449.
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碩士<br>國立中興大學<br>化學工程學系所<br>102<br>Based on phosphorus-containing polymer P5, and polymer P5-N3 which was prepared by P5 and polyformadehyde, we produced epoxy resins P5-EP and P5-N3-EP. The structures of P5-EP and P5-N3-EP were confirmed by FTIR and NMR spectra. By checking epoxy equivalent weight with theoretical value, we produced high purity epoxy resins.
Then, P5-EP and P5-N3-EP were curing with amine、benzoxazine and phenol novolac. Properties such as glass transition temperature, coefficient of thermal expansion, thermal decomposition temperature, and flammability of the resulting epoxy thermosets were evaluated and compared with each other. Because of high epoxide functional group numbers , the resulting of P5-N3-EP thermoset shows high Tg, high char
yield and excellent flame retardancy.
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Fröhlich, Jörg [Verfasser]. "Nanostructured thermoset resins and nanocomposites containing hyperbranched blockcopolyether liquid rubbers and organophilic layered silicates = (Nanostrukturierte Duromere und Nanocomposite auf der Basis von hyperverzweigten Polyether-Flüssigkautschuken und organophilen Schichtsilikaten) / vorgelegt von Jörg Fröhlich." 2003. http://d-nb.info/968525865/34.
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