Дисертації з теми "Nanofilled composites"
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Masouras, Konstantinos. "Elastic and surface properties of model nanofilled resin-composites." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509838.
Повний текст джерелаScotti, Nicola. "Laboratory evaluation of several nanofilled dental resin composites: mechanical and chemical properties." Doctoral thesis, Università degli studi di Trieste, 2015. http://hdl.handle.net/10077/10899.
Повний текст джерелаThe present thesis focused on nanofilled dental resins. The first year activity focused on depth of cure analysis of nanofilled composites. The second year activity focused on hardness, depth of cure and shrinkage stress analysis of bulk fill resin composites. The third year focused on degree of conversion and hardness of nanofilled resin cements.
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Raza, Mohsin Ali. "Carbon nanofiller-based composites for thermal interface applications." Thesis, University of Leeds, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.574596.
Повний текст джерелаSILVA, MARIANA DO NASCIMENTO. "GRAPHENE AS NANOFILLER IN COMPOSITES FOR ANTICORROSIVE PROTECTION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36392@1.
Повний текст джерелаCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTITUIÇÕES COMUNITÁRIAS DE ENSINO PARTICULARES
O nanocompósito estudado com função de revestimento anticorrosivo é constituído de Epóxi Novolac Tipo II aditivado com grafeno, sintetizado através do processo de esfoliação/redução do grafite empregando microondas. O sistema epóxi utilizado é composto pelos componentes: A, baseado em bisfenol F e cargas inorgânicas, e o B, endurecedor baseado em um polímero aminado. A síntese do grafeno e sua aditivação no componente A, foram realizadas pelo CTNano - UFMG. O principal objetivo desta dissertação é o estudo da aplicabilidade do nanocompósito, onde o grafeno é utilizado como aditivo complementar em matriz polimérica (epóxi), como alternativa de maximizar a proteção anticorrosiva. Foram estudadas diferentes aditivações: CR (sem aditivo), e aditivadas (0.1 por cento e 0.5 por cento). O substrato utilizado foi o aço carbono 1020, cuja superfície foi preparada com jateamento abrasivo e em seguida revestida com uma pistola de ar comprimido e com solvente para auxiliar o processo. Para avaliar a eficiência destes revestimentos foram realizados ensaios de corrosão (Célula Atlas e Ensaios Cíclicos), teste de aderência (Pull Off), medida de espessura (MEV) e rugosidade do substrato através do rugosímetro analógico e microscopia óptica. Para a dispersão do grafeno foi adicionado diglidil éter de bisfenol A (DGEBA) como um diluente. Os resultados obtidos indicaram que o grafeno apresentava boa dispersão na matriz polimérica. Concentrações de grafeno acima de 0,1 por cento em massa levam à falha da proteção anticorrosiva. Este comportamento pode estar relacionado à presença de solvente residual ou DGEBA não reagido no sistema com grafeno, além de possível atuação de grafeno agregado como ponto de tensão. O mecanismo de adesão revestimento/substrato permaneceu inalterado para todas as aditivações estudadas.
The studied nanocomposite with anticorrosive coating function is composed of Novolac Type II epoxy added with graphene, synthesized through the process of exfoliation / reduction of graphite using microwaves. The epoxy system used consists of the following components: A, based on bisphenol F and inorganic fillers, and B, hardener based on an amino polymer. The synthesis of graphene and its additivation in component A were performed by CTNano - UFMG. The main objective of this dissertation is the study of the applicability of the nanocomposite, where graphene is used as complementary additive in polymer matrix (epoxy), as an alternative to maximize anticorrosive protection. Different additives were studied: CR (without additive), and additives (0.1 percent and 0.5 percent). The substrate used was carbon steel 1020, the surface of which was prepared with abrasive blasting and then coated with a compressed air and solvent gun to aid the process. To evaluate the efficiency of these coatings were performed corrosion tests (Atlas Cell and Cyclic Tests), Pull Off test, thickness measurement (MEV) and roughness of the substrate through the analogous rugosimeter and optical microscopy. For the dispersion of graphene, diglycidyl ether of bisphenol A (DGEBA) was added as a diluent. The results indicated that graphene showed good dispersion in the polymer matrix. Concentrations of graphene above 0.1 percent by mass lead to failure of the anticorrosive protection. This behavior may be related to the presence of residual solvent or unreacted DGEBA in the graphene system, in addition to the possibility of aggregated graphene as voltage point. The coating / substrate adhesion mechanism remained unchanged for all additives studied.
Xiang, Dong. "Processing and properties of melt processed high density polyethylene-carbon nanofiller composites." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.676504.
Повний текст джерелаKelnar, I. "Polymer-polymer Microfibrillar Composites: Effect of Nanofillers on Structure and Properties." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35451.
Повний текст джерелаLutz, Vincent. "Carbon nanotubes as nanofillers or fibers for multifunctional epoxy-based composites." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0039.
Повний текст джерелаNowadays, polymer-matrix composites reinforced with carbon fibers are increasingly used in the whole transport sector (aerospace, automotive and railway industries). However, the obtained parts still suffer from low impact resistance and low damage tolerance. To improve these properties, the matrix precursors have to be combined with organic or inorganic compounds to lead to multi-phased matrices. Among them, carbon nanotubes (CNT) are especially promising for targeting multi-scale reinforcement. Since high quality of the parts are required, continuous-fibers-reinforced composites can be produced by resin transfer molding (RTM) which also offers a reduced cost if compared with high temperature- and high pressure-based processes. However, RTM requires a very low viscosity of the polymer precursors and CNT-filled precursors are far too viscous to be injected on dry performs. In addition, this strategy does not allow for a control of the CNT location and orientation in the final part. In this study, innovative ways have been developed to insert CNT in the preform with local positioning and defined orientation. Deliveries of CNT in the matrix, from a neat carbon multi-nanotubes fiber produced by direct spinning, or from a CNT grown on carbon fiber were investigated in two types of epoxy matrices (with very different TG). Different polymer matrix/fiber interfaces have been generated using neat carbon multi-nanotubes fiber, CNT grown on carbon fiber and conventional carbon fiber, with or without sizing. A fine mechanical characterization of various fibers and particularly the measurement of single fiber interfacial properties have been performed in order to determine mechanical performance of continuous fiber reinforced composites. In addition, the nature of adhesion and quality of matrix/fiber interface have been fully evaluated by different multi-scale analyses and suitable microstructural observations
LASIO, BARBARA. "Fabrication of Cu-based metal matrix composites reinforced with carbon nanofillers." Doctoral thesis, Università degli Studi di Cagliari, 2019. http://hdl.handle.net/11584/260760.
Повний текст джерелаWang, X., Q. Zheng, S. Dong, Ashraf F. Ashour, and B. Han. "Interfacial characteristics of nano-engineered concrete composites." Elsevier, 2020. http://hdl.handle.net/10454/17954.
Повний текст джерелаThis study investigates the interfacial characteristics between aggregates and cement paste matrix in nanofillers modified concrete. A three-point bend test on the specimens composed of two pieces of aggregates bonded with a thin layer of cement pastes with/without nanofillers was carried out to characterize the interfacial bond strength of the composites. The scanning electron microscope observations and energy dispersive x-ray spectrometry analysis were also performed to characterize the interfacial microstructures and compositions of the composites. The experimental results indicated that the nanocomposites have higher interfacial bond strength and narrower interfacial transition zone thickness as well as more optimized intrinsic compositions and microstructures than that of composites without nanofillers. Specifically, the interfacial bond strength of nanocomposites can reach 7.67 MPa, which is 3.03 MPa/65.3% higher than that of composites without nanofillers. The interfacial transition zone thickness of nanocomposites ranges from 9 μm to 12 μm, while that of composites without nanofillers is about 18 μm. The ratio of CaO to SiO2 in the interface of composites without nanofillers is 0.69, and that of nanocomposites increases to 0.75–1.12. Meanwhile, the nanofiller content in nanocomposite interface is 1.65–1.98 times more than that in the bulk matrix. The interfacial microstructures of nanocomposites are more compact and the content and crystal size of calcium hydroxide were significantly reduced compared with that of composites without nanofillers.
The National Science Foundation of China (51978127 and 51908103), and the China Postdoctoral Science Foundation (2019M651116).
Jumahat, Aidah. "Effect of nanofillers on thermo-mechanical properties of polymers and composite laminates." Thesis, University of Sheffield, 2011. http://etheses.whiterose.ac.uk/12875/.
Повний текст джерелаChatterjee, Sanjukta. "Structural and Physical Effects of Carbon Nanofillers in Thermoplastic and Thermosetting Polymer Systems." Doctoral thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-171449.
Повний текст джерелаPang, Le. "Development of mechanically enhanced polycaprolactone (PCL) composites silane: Functionalized titanate nanofiller for melt electrowriting in 3D printing." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/206450/2/Le_Pang_Thesis.pdf.
Повний текст джерелаRaimondo, Marialuigia. "Improving the aircraft safety by advanced structures and protecting nanofillers." Doctoral thesis, Universita degli studi di Salerno, 2014. http://hdl.handle.net/10556/1480.
Повний текст джерелаInspection and Maintenance are important aspects when considering the availability of aircraft for revenue flights. Modern airframe design is exploiting new exciting developments in materials and structures to construct ever more efficient air vehicle able to enable efficient maintenance. The improvement in the aircraft safety by advanced structures and protecting nanofillers is a revolutionary approach that should lead to the creation of novel generation of multifunctional aircraft materials with strongly desired properties and design flexibilities. In recent years, the development of new nanostructured materials has enabled an evolving shift from single purpose materials to multifunctional systems that can provide greater value than the base materials alone; these materials possess attributes beyond the basic strength and stiffness that typically drive the science and engineering of the material for structural systems. Structural materials can be designed to have integrated electrical, electromagnetic, flame resistance, and possibly other functionalities that work in synergy to provide advantages that reach beyond that of the sum of the individual capabilities. Materials of this kind have tremendous potential to impact future structural performance by reducing size, weight, cost, power consumption and complexity while improving efficiency, safety and versatility. It is a well-known fact that, actually, also a very advanced design of an aircraft has to take required inspection intervals into account. An aircraft with inherent protective abilities could help to significantly extend the inspection intervals, thereby increasing aircraft availability. The challenge in this research is to develop and apply a multifunctional composite for structural applications. The aim of this project is the formulation, preparation and characterization of structural thermosetting composites containing dispersed protective nanofillers. This project specifically targets composites tailored for multifunctional applications such as lightning strike protection, and flame resistance. These composites were designed to enable their application on next generation aircrafts. With regard to the objectives of this PhD project the multifunctional composite systems were developed with the aim of overcoming the following drawbacks of the composite materials: • reduced electrical conductivity; • poor flame resistance. The thermosetting material was projected considering compatibility criteria so that to integrate different functions into a material that is capable of bearing mechanical loads and serves as a structural material element. [edited by author]
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Hudec, Jiří. "Sledování vlastností nanokompozitních materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220100.
Повний текст джерелаPedrazzoli, Diego. "Understanding the effect of nanofillers on the properties of polypropylene and glass fiber/polypropylene multiscale composites." Doctoral thesis, Università degli studi di Trento, 2014. https://hdl.handle.net/11572/368547.
Повний текст джерелаKilbride, Marianne. "Influence of carbon nanographite and other nanofillers on the properties of thermoset : thermoplastic blends for composite matrices." Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=12800.
Повний текст джерелаGouveia, Thayla Hellen Nunes 1985. "Efeito do envelhecimento artificial acelerado, clareamento e manchamento nas propriedades físicas de um compósito nanoparticulado = Effect of accelerated artificial aging, bleaching and staining of physical properties of a nanofilled composite." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290657.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo in vitro foi avaliar as propriedades físicas de uma resina composta nanoparticulada submetida ao envelhecimento artificial acelerado (AAA), ação de agentes clareadores e manchamento extrínseco. O estudo foi dividido em 2 experimentos. O experimento 1 avaliou a influência do AAA e do peróxido de carbamida a 16% com diferentes espessantes na retenção do brilho (GU), cor (?E), microdureza (KHN) e rugosidade média (Ra) de superfície do compósito. A análise qualitativa da superfície de resina foi realizada através de microscopia de força atômica. Cem amostras cilíndricas (7,0mm x 2,0mm) foram confeccionadas e distribuídas aleatoriamente em 10 grupos (n=10). Somente metade dos grupos foram envelhecidos. Para o tratamento clareador/espessante, os grupos com e sem AAA foram divididos em: peróxido de carbamida 16% (PC) com carbopol, PC com natrosol, gel de carbopol, gel de natrosol e sem tratamento (controle). Os dados obtidos foram analisados por meio de ANOVA dois fatores e teste de Tukey. Para o ?E as comparações múltiplas foram realizadas pelos teste de Tukey e Dunnett. Os valores de rugosidade foram analisados pelos testes de Kruskal Wallis, Dunn e Mann Whitney. O nível de significância considerado foi de 5%. O PC com carbopol promoveu redução apenas na microdureza do compósito, diferindo estatisticamente do controle. Para o PC com natrosol esta alteração não foi observada. O PC com carbopol aumentou a rugosidade e diminuiu o brilho das resinas envelhecidas, enquanto o natrosol só o briho foi reduzido, diferindo estatisticamente do grupo controle. O Experimento 2 avaliou a influência dos tratamentos clareadores em diferentes concentrações e manchamento com café na propriedades físicas anteriormente citadas da resina nanoparticulada, submetidas ou não ao AAA. Duas amostras representativas de cada grupo foram avaliadas em microscopia eletrônica de varredura. Cento e vinte amostras cilíndricas foram confeccionadas, semelhante ao estudo anterior, distribuídas em 12 grupos (n=10). Metade das amostras foram envelhecidas artificialmente. Para o tratamento clareador/pigmentação, os grupos com e sem AAA, foram divididos em: peróxido de carbamida a 10% (PC 10%), peróxido de hidrogênio a 35% (PH 35%) e sem tratamento clareador, com e sem pigmentação por café. Os dados foram coletados e submetidos a ANOVA três fatores e teste de Tukey para comparações múltiplas. Para o ?E as comparações múltiplas foram realizadas pelos testes de Tukey e Dunnett (?=0,05). Nas resinas sem envelhecimento, os agentes clareadores reduziram a microdureza do compósito, entretanto a rugosidade, brilho e cor não apresentaram alterações. Após o envelhecimento, o PC 10% aumentou a rugosidade e diminuiu o brilho comparado ao PH 35%. A pigmentação também reduziu a microdureza das resinas sem e com envelhecimento e alterou a cor das resinas envelhecidas (?E>25). Portanto, a ação dos géis clareadores reduziu a microdureza do nanocompósito, sendo que a composição do gel clareador influenciou nessa alteração. O AAA promoveu significativas alterações nas propriedades físicas avaliadas, além de favorecer uma maior degradação da superfície da resina pelo agente clareador e este efeito contribuiu para um maior manchamento extrínseco
Abstract: The aim of this in vitro study was to evaluate the physical properties of a nanocomposite subjected to artificial accelerated aging (AAA), to the action of bleaching agents and to extrinsic staining. This study was divided into two experiments. Experiment 1: evaluate the influence on a composite surface of AAA and 16% carbamide peroxide with different thickeners, in gloss retention (GU), color (?E), microhardness (KHN) and roughness (Ra). Qualitative analysis of the resin surface was performed by atomic force microscopy. One hundred cylindrical samples (7.0mm x 2.0mm) were prepared and randomly divided into 10 groups (n = 10). Only half of the groups were aged. For the bleaching/thickening treatment, the groups with and without AAA were divided into groups/ treatments: 16% carbamide peroxide (PC) with carbopol, PC natrosol, carbopol gel, natrosol gel and untreated (control). Data were submitted to two-way ANOVA and Tukey¿s test for multiple comparisons. The multiple comparisons for ?E were performed by using Tukey¿s and Dunnett¿s tests, and roughness values was analysed by using Kruskal-Wallis, Dunn¿s, and Mann-Whitney¿s tests (? =0.05). The PC with carbopol promoted a decreased in the composite microhardness differing significantly from the control. As for CP + natrosol this change in the microhardness was not observed. The treatment with CP + carbopol increased the roughness and decreased the gloss of the aged resins, whereas natrosol reduced only the gloss which differed statistically from the control. Experiment 2: evaluate the influence of bleaching treatments with different concentrations and coffee staining, in the physical properties of nanocomposite, submitted or not to AAA. Two representative samples of each group were evaluated in scanning electron microscopy (SEM). One hundred twenty cylindrical samples were prepared similar to the previous study and divided into 12 groups (n = 10). Half of specimens were artificially aged. For the bleaching/pigment treatment, groups with and without AAA, were divided into the following groups: 10% carbamide peroxide (10% CP), 35% hydrogen peroxide (35% PH) without bleaching treatment, with and without pigmentation of coffee. Data were submitted to three-way ANOVA and Tukey¿s test for multiple comparisons. The multiple comparisons for ?E were performed by using Tukey¿s and Dunnett¿s tests (?=0,05). The resins without aging, the bleaching agents promoted a reduction in the composite microhardness, however, in the roughness, gloss and color this changes were not observed. After aging, the pigmentation also reduced the microhardness of the resins with and without aging and altered the color of the aged resins (?E> 25). 10% PC increased roughness and decreased gloss compared to 35% PH. Pigmentation also reduced the microhardness of the resins with and without aging and change the color of the aging resins (?E> 25). The action of bleaching agents reduced the microhardness of the nanocomposite, and this alteration was influenced by the composition of the bleaching gel. The AAA promoted significant changes in the evaluated physical properties and favored the further deterioration of the resin surface by the bleaching, contributing to a greater extrinsic staining
Mestrado
Dentística
Mestra em Clínica Odontológica
IEZZI, IOLANDA. "Age-related regenerative potential of human Dental Pulp Stem/Stromal Cells (hDPSCs): possible consequences in an ageing society." Doctoral thesis, Università Politecnica delle Marche, 2020. http://hdl.handle.net/11566/274614.
Повний текст джерелаUncomplicated dental treatments for pulpitis and periodontitis continues to be challenging especially in elderly, and regenerative approaches could meet this contingency. Ageing is a physiologic phenomenon occurring with time, which hamper the organs’ functional capacity that normally maintains tissue homeostasis and physiological responses. Moreover, it is well known that aged cells significantly affect their microenvironment, as they secrete pro-inflammatory and matrix-degrading molecules. The impact of these factors on Mesenchymal Stem/Stromal Cells (MSCs) could be also of interest for a better understanding of the age-related regenerative potential. Since Dental Pulp Stem/Stromal cells (DPSCs) represent a good candidate for oral restorative therapies, the study of age-related changes in their recovering capability could be crucial for developing customized treatments for an ageing society. In our in vitro investigations, we firstly analysed changes in the morphology, proliferation, and differentiation toward mesenchymal, odontoblastic and neuronal phenotypes of human DPSCs (hDPSCs) harvested from differently aged donors. Then, we studied the effects of an age-related microenvironment on the biological performances of hDPSCs isolated from young and old subjects. Cytofluorimetric, immunohistochemical, quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR), and western blot analyses were performed. We observed a decline in hDPSCs proliferation and differentiation potential with age. Moreover, these cells showed distinct age‐related mineralization capabilities as well as neurogenic differentiation. In addition, cell-conditioned media from an age-related microenvironment was able to modify the behaviour of hDPSCs isolated from young or old subjects. Later, aimed to combine the conventional restorative dentistry with the recent regenerative techniques, the in vitro impact of a commonly used nanofilled composite (Filtek Supreme XTE) on hDPSCs was taken into account. In this research, proliferation, apoptosis, differentiation ability as well as matrix mineralization, of hDPSCs cultured in the presence of a nanofilled composite were examined. Our data demonstrated that Filtek Supreme XTE affects and delays hDPSCs differentiation and mineralization processes when compared to a control group with dentin-slices as well as in tissue culture plates. This initial approach performed with young cells paves the ways for future studies with hDPSCs derived from old subjects, in order to develop a bioactive material customised for an ageing population In conclusion, our results confirmed that ageing differently impaired hDPSCs biological properties and local factors may modulate these processes. Our observations represent a valid tool for the development of tailored regenerative strategies in an ageing society.
Daloia, Debora. "Friction and Wear Behavior of Graphene Reinforced Epoxy." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1403532384.
Повний текст джерелаYang, Jing. "Phosphonium ionic liquids : Versatile nanostructuration and interfacial agents for poly(vinylidene fluoride-chlorotrifluoroethylene)." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI072/document.
Повний текст джерелаThis thesis work deals with an understanding of the versatile roles of phosphonium ionic liquids (ILs) as nanostructuration and interfacial agents for the fluorinated polymer matrix, i.e.,poly(vinylidene fluoride-chlorotrifluoroethylene) (P(VDF-CTFE)). In this context, two phosphonium ILs with different functionalities in steric hindrance and extra dipolar groups are firstly incorporated in P(VDF-CTFE) matrix to prepare polymer films. The crystalline phase structure, dispersion morphology and crystallization behavior are finely characterized with the goal of providing a full and deep understanding of the versatile and tunable nanostructuration effect of phosphonium ILs. Subsequently, in order to elucidate the mechanism of interfacial influence of IL, a fluorinated phosphonium IL with a cation structure combining three phenyls and a short fluorinated chain is added on the surface of graphene oxide (GO) and reduced graphene oxide (rGO), making them as functional nanofillers to be incorporated into P(VDF-CTFE) matrix. Thus,P(VDF-CTFE)/graphene composite films with different filler contents are prepared in order to investigate the mechanism of interfacial interaction and its influence on the composite films, such as crystalline phase structure, crystallization behavior, chain segmental relaxation behavior, dispersion morphology and the final dielectric properties
Liu, Yang. "‘Tri-3D’ electron microscopy tomography by FIB, SEM and TEM : Application to polymer nanocomposites." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0076/document.
Повний текст джерелаThis work is focused on the characterization and quantification of the 3D distribution of different types of fillers (nanoparticles, nanotubes, etc.) in polymer matrices. We have essentially used tomography techniques in electron microscopy. Multiple approaches to electron tomography were performed: FIB-SEM (focused ion beam/scanning electron microscope) tomography, SEM tomography and TEM (transmission electron microscope) tomography. Polymer nanocomposites are basically synthesized in order to improve the physical properties (mechanical, electric, etc.) of the pure polymer constituting the matrix, by a controlled addition of fillers at the nanoscale. The characterization of such materials and the establishment of accurate correlations between the microstructure and the modified properties require a three-dimensional approach. According to the nanometric size of the fillers, electron microscopy techniques are needed. Two systems of polymer nanocomposites have been studied by multiple electron tomography approaches: P(BuA-stat-S)/MWNTs (statistical copolymer poly(styrene-co-butyl acrylate) reinforced by multi-walled carbon nanotubes) and P(BuA-stat-MMA)/SiO2 (statistical copolymer poly(butyl acrylate-co-methyl methacrylate) reinforced by silica nanoparticles). By combining various techniques, the characterization and the quantification of nanofillers were possible. In particular, statistics about size, distribution and volume fraction of the fillers were measured. This study has then provided 3D information, which contributes to a better understanding of properties of the nanocomposites. Attention has been paid to analyze carefully original data, and artifacts and causes of errors or inaccuracy were considered in the 3D treatments. We also attempted to compare benefits and drawbacks of all techniques employed in this study, and perspectives for future improvements have been proposed
Xie, Ming-Yue, and 謝明岳. "Study of High Voltage Insulator with the Characteristics of Nanofilled Insulation Composite." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/52770253382567482201.
Повний текст джерела國立聯合大學
電機工程學系碩士班
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In power systems, insulators can ensure the isolation between the transmission line and the ground, therefore the stability of the power systems is closed related to the insulation characteristics of insulators. Insulation characteristics of the insulators mainly depend on the material used in insulator manufacturing, the shape design of the insulators and the coating conditions on the surface of insulators. In addition to the traditional porcelain insulators, the polymer insulators are also widely used in power systems. The contour design can improve the tangential electric field of the surface of the insulators to decrease the probability of the surface flashover of the insulators. The coating on the surface of the insulators can enhance the hydrophobicity on the surface of the insulators to improve the insulation performance of insulators. After measuring the samples of the epoxy resin filled with nanoparticles, the breakdown voltage increases with the thickness of the samples. The dielectric constant of samples are positive correlated to the density of the filler in the samples. The samples with 5 wt% SiO2 nanoparticles have the highest breakdown voltage and the samples with 5 wt% Al2O3 nanoparticles have the more stable failure rate. In the samples groups of 5 wt% nanoparticles, the samples with calcination of mixed SiO2 and Al2O3 have higher dielectric constant. The contour design of insulators is performed by the genetic algorithm merged with the charge simulation method. The optimal contour of the insulators changes with the constraints. The results of insulator coating with RTV silicone rubber shows that the BaTiO3 3 wt% filled can get the best hydrophobicity, and the smallest leakage current occurs at the BaTiO3 10 wt% filled.
Mora, Cordova Angel. "A Morphology Study of Nanofiller Networks in Polymer Nanocomposites: Improving Their Electrical Conductivity through Better Doping Strategies." Diss., 2018. http://hdl.handle.net/10754/627412.
Повний текст джерела(10725372), Rajan Nitish Jain. "Intrinsic Self-Sensing of Pulsed Laser Ablation in Carbon Nanofiber-Modified Glass Fiber/Epoxy Laminates." Thesis, 2021.
Знайти повний текст джерелаLi, Wenjing [Verfasser]. "PET-PP-based polymer composites : effects of compatibilizer and nanofillers on the processing structure property relationships / von Wenjing Li." 2009. http://d-nb.info/999353039/34.
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