To see the other types of publications on this topic, follow the link: Micro- and nano-composite.
Dissertations / Theses on the topic 'Micro- and nano-composite'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 26 dissertations / theses for your research on the topic 'Micro- and nano-composite.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Zhao, Hang. "Comportement multifonctionnel des composites comportant des nano/micro renforts." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLC020/document.
Full textAbstract:
En raison de leurs propriétés mécaniques, électriques et thermiques exceptionnelles, les nanotubes de carbone (NTC) ont reçu une importante attention mondiale. Les NTC ont un grand potentiel dans différents domaines d'applications tels que le stockage d'énergie et la microélectronique. Grâce à leur structure unidimensionnelle, leur important facteur d'aspect et leur faible densité, les NTC servent comme charges dans les composites. Par contre, en raison des fortes interactions entre eux, il est difficile de les disperser et de les aligner dans une matrice de polymère.Il est connu qu'une bonne conception d'hybrides, constitués de NTC verticalement lignés sur des substrats, améliore de manière significative la dispersion de ces derniers dans la matrice. Ces hybrides sont préparés par le procédé de dépôt chimique en phase vapeur (CVD). Une fois, ces hybrides sont dispersés dans la matrice du composite cela conduit à une nette amélioration des propriétés multifonctionnelles de ce composite. Les substrats utilisés dans cette thèse sont les nanoplaquettes de graphite (NPG) pour donner des hybrides NPG-NTC que nous appellerons par la suite GCHs. Les GCHs ont l'avantage d'avoir une faible densité et une structure totalement conductrice qui améliore les propriétés diélectriques et électriques des composites.Dans l'état de l'art, les relations entre l'organisation des GCHs et les conditions de synthèse par CVD et entre l'ajout des GCHs dans les composites et les réseaux conducteur interne dans les composites n'ont jamais été étudiées. Pour cela, dans cette thèse, nous allons soigneusement étudier et discuter ces problèmes mentionnés.Dans le premier chapitre, nous présentons une revue générale de la structure, des propriétés, des applications et de la synthèse des NTC et des NPG. Nous présentons aussi les procédures de l'intégration des nanoparticules dans des matrices polymères et les méthodes de fonctionnalisation des NTC. Nous discutons aussi des états électriques et les caractéristiques (di)électriques des composites en fonction de la quantité de la charge conductrice.Le deuxième chapitre présente tout d'abord la synthèse des NTC sur les NPG par CVD. Ensuite, l'influence des paramètres de la CVD, la température, la composition du gaz et le temps de la réaction, ont été étudié. Les résultats qualitatifs et quantitatifs obtenus d'après les caractérisations des ces hybrides peuvent servir comme base de données pour l'intégration et l'influence des ces hybrides dans les composites.Le troisième chapitre présente les composites binaires polyvinylidene fluoride/GCHs et leurs propriétés diélectriques qui sont nettement améliorées par rapport aux composites ternaires composés de polyvinylidene fluoride/NPG/NTC. Les composites obtenus par dispersion des GCHs dans la matrice à l'aide du procédé d'extrusion-injection, présentent un seuil de percolation fortement réduit (5,53 vol%) et une stabilité thermique relativement élevée. Leurs propriétés diélectriques améliorées peuvent être attribuées à des réseaux sous forme de micro-condensateurs et le changement de la cristallinité de la matrice peut être attribué à la bonne conception des hybrides.Le quatrième chapitre étudie les composites GCHs/polydiméthylsiloxane (PDMS) avec la haute performance piézo-résistive dans une large gamme de température. Le composite présente un seuil de percolation ultra-bas et une grande sensibilité piézo-résistive. En particulier, les autres améliorations des propriétés électriques obtenues dans les composites GCHs/PDMS par rapport à celles des composites à base de NTC/PDMS, de NPG/PDMS ou encore de NTC-NPG/PDMS. Les légers mouvements des doigts peuvent être détectés grâce à l'usage de ces films composites en tant que capteurs de mouvement<br>Due to the outstanding mechanical electrical and thermal properties, carbon nanotubes (CNTs) received worldwide attentions and intensive investigations in last decades. CNTs are greatly potential in applications such as energy storage and microelectronics. The one dimensional structure, high aspect ratio and low density, promote CNTs serving as the excellent fillers in composites field. However, due to the strong interactions, CNTs are usually difficult to be dispersed and aligned in a polymer matrix. Designing the CNTs construction reasonably is an effective way to ameliorate the dispersion states of CNTs in matrix. These specific hybrid constructions allowed CNTs arrays synthesized vertically onto the substrates through catalyst chemical vapor deposition method. These CNT arrays effectively overcome the problem of CNTs aggregation and promote the interconnection among CNTs, leading to a considerable improvement of multi-functional properties of composites. Graphite nanoplatelets (GNPs) served as substrate make their synthesizing products-GNP-CNTs hybrids (GCHs) possess distinct merits of all-carbon composition, totally-conductive coupling structure and the low intrinsic density. These GCHs constructions provide a great improvement in the dielectric and electrical properties of composites. However, the relationship between GCHs organization and synthesizing conditions during CVD process and the influence of the addition of GCHs to internal conductive networks have not been reported in detail. These mentioned issues will be investigated and discussed in this thesis, which is divided into four chapters:The first chapter makes a general review of the structure, properties, application and synthesis of CNTs and GNP substrates, and the main procedures of fabricating composites and surface functionalization of CNTs. Moreover, a short introduction of the development of micro-nano hybrids applied to the functional composites is made. Most importantly, the developing electrical states and (di) electrical characteristics of composites with ever-increasing conducting filler loading are reviewed in detail at the last part.The second chapter discusses firstly the synthesis process through the CCVD approach and the relationship between CVD parameters and the corresponding construction of GCHs, where the temperature, gas composition and reaction time were controlled. The constructions CNT arrays are dependent on the synthesis conditions. Furthermore, the results obtained from analysis can provide a structural foundation for the huge application potential of GCHs constructions. The third chapter introduces the poly(vinylidene fluoride)-based nanocomposites containing GCH particles, the dielectric properties of which are improved more greatly than the ternary composites loading equivalent mixture of GNPs and CNTs. The composites achieved by dispersing GCH particles into matrix using the mechanical melt-mixing process, showing a strongly reduced percolation threshold (5.53 vol %) and the relatively high thermal stability. Their improved dielectric properties can be attributed to the formed microcapacitor networks and the change of crystalline formation of matrix, caused by well-designed CNT arrays constructions. The fourth chapter investigates the advanced GCHs/ polydimethylsilicone (PDMS) composites with high piezo-resistive performance at wide temperature range. The synthesized GCHs can be well dispersed in the matrix through the mechanical blending process. The flexible composite shows an ultra-low percolation threshold (0.64 vol%) and high piezo-resistive sensitivity (gauge factor ~103 and pressure sensitivity ~ 0.6 kPa-1). Particularly, the much improvements of electrical properties achieved in GCHs/PDMS composites compared with composites filled with equivalent CNT, GNP or mixture of CNTs/GNPs. Slight motions of finger can be detected and distinguished accurately using the composites film as typical wearable sensor
2
Recman, Lukáš. "Deformační chování nano/mikro vyztuženého PMMA." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-233297.
Full textAbstract:
Práce sleduje vliv velikosti částic na elastický modul a deformační chování za mezí kluzu. Bylo pozorováno, že jak elastická oblast, tak oblast za mezí kluzu ukazuje silnou závislost chování na velikosti částic. Cílem této práce je korelovat experimentální data a teoretické předpoklady které bylo odvozeny pro deformační chování v elastické oblasti a v oblasti za mezí kluzu pro amorfní polymery a konkrétně pro PMMA. Vše je motivováno propojit zatím oddělené oblasti kontinuální mikromechaniky a diskrétní nanomechaniky. Deformační chovaní PMMA plněného nano a mikro plnivem bylo pozorováno v elastické a plastické oblasti. Byl zkoumán vliv velikosti částic na velikost modulu a deformačního zpevnění. Mechanizmus vyztužení je interpretován s použitím teorie imobilizace řetězců, nanočástice mají silný vliv na molekulární dynamiku a kinetiku zapletenin. Mým příspěvkem k tomuto tématu je ukázat výraznou závislost na mechanizmu vyztužení v závislosti na velikosti částic. A to jak pod teplotou skelného přechodu tak nad teplotou skelného přechodu. Ačkoli pro velikost modulu byla publikována značná množství dat, která byla následně i interpretována, vliv částic na deformační zpevnění je poskrovnu. Během elastické deformace je primární struktura materiálu neměnná, jedná se o elastickou deformaci, za mezí kluzu již toto neplatí a primární struktura je zde nevratně poškozena. Bylo ukázáno, že obsah nano částic vede ke zvýšení meze kluzu a vyššímu deformačnímu zpevnění. Tento nárůst deformačního zpevnění je v korelaci s Guth-Gold rovnicí. Je předpokládáno, že nanočástice slouží jako další fyzikální zapleteniny a vedou k fyzikálně více zapletenému systému. Stejný efekt jako v elastické oblast tj. vliv velikosti částic na modul, byla pozorována i během deformačního zpevnění.
3
Greco, Pier Paolo. "Development of novel polymeric and composite nano-structured micro-porous materials for impact resistance applications." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2517.
Full textAbstract:
Impact resistant materials (IRMs) are widely used in the automotive and packaging industry. Their main purpose is the protection of the transported occupants or goods. Cellular materials as well as structures combine lightness with large deformation under load. The energy absorption mechanism is provided by limiting the peak load and ensuring the elastic deformation of the IRMs. Polymeric foams are largely used as IRMs due to their cellular structure. Prediction of the foam properties in terms of Young’s Modulus (Elastic Modulus) and the onset of Plateau Region can be related to the foam density and the mechanical properties of the bulk material (Gibson and Ashby model). The structure of the foam is only partly accounted for in the Gibson and Ashby model in terms of material density. However, it is possible to produce cellular materials with the same density but very different internal architectures. This cannot easily be exploited in conventional polymer foams but the processing of High Internal Phase Emulsion (PolyHIPE) and its polymerisation route to produce PolyHIPE Polymers (PHPs) can produce materials with very different structures. Experiments have revealed that the PHPs properties are dictated by their detailed structure. Elastic PHPs with: 1) varying ratio of polymerizable oil phase with respect to aqueous phase and 2) varying mixing time/energy input were produced and tested by mechanical compression at different temperatures and strain rates. The elastic modulus increases with a quadratic law as a function of the polymerizable oil phase content of the HIPE when the mixing time is the same, as predicted by the model. The Specific Absorption Energy (SAE), represented by the area under the stress-strain curve, increases in a similar way. Increasing mixing time on HIPE has the effect of modifying the cellular structure. Smaller pores and narrower distribution of pores are observed. Such features are consistent for any set of PHPs densities and represent a design tool when some specific mechanical characteristics are prescribed. The assessment of process-structure-properties relationships was performed by combining the mechanical response of the various PHPs with the imaging of their structure by Scanning Electron Microscopy. The properties of PHPs were benchmarked with reference to two commercially available products. One material is characterised by a porous structure with a relatively high Young’s Modulus while the other by a non-porous and composite-like solid structure with lower elastic modulus. The properties of the PHPs can be engineered to shift from a foam-like material to a composite-like through the processing parameters which in turn modify the material porous structure. The temperature has very limited effect on the PHPs material unlike for the reference commercial materials. The enhancement of properties (increasing Elastic Modulus and SAE) induced by changing the processing route are remarkable for such a class of porous materials. When plotted on a Modulus-Density chart, the PHPs fill an existing material-chart gap, representing a new class of materials and opening new possibilities as IRMs.
4
Ha, Hung M. "Micro- and Nano-Scale Corrosion in Iron-Based Bulk Metallic Glass Sam 1651 and Silver-cored MP35N Lt Composite." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1260391940.
Full text
5
Wojcieszak, Marine. "La soie, "modèle" de polymères naturels fibreux : analyse vibrationnelle et nano/micromécanique, de la fibre au composite." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066506/document.
Full textAbstract:
Les protéines fibreuses (kératine, élastine, collagène, fibroïne…) représentent 1/3 des protéinesconstitutives des mammifères et des oiseaux. Ce sont des protéines qui ont une fonction de protection et/oumécanique. La soie apparait comme le système le plus « simple » car elle est principalement constituée demotifs de répétition à base d’alanine et de glycine, deux petits acides aminés. Certaines soies présentent despropriétés mécaniques comparables ou supérieures à celles des fibres synthétiques et seraient susceptiblesd’être de nouveau largement utilisées dans des applications techniques (par exemple biomédicales) si lavariabilité de leurs propriétés était maîtrisée. Ce travail porte sur la structure des soies grèges ou décreuséesde Bombyx mori (ver à soie domestique), de Nephila madagascariensis (araignée sauvage, fibre sansenveloppe de séricine), de Bombyx mori génétiquement modifié (incluant un gène de Nephila) et sur unesoie recombinante 4RepCT (Escherichia coli). La soie est analysée par spectrométrie Raman (et IRTF) ettraction uni-axiale, ainsi que par le couplage de ces méthodes. L’analyse de la région des bas nombresd’onde en spectroscopie Raman a permis de caractériser des régions ordonnées de 2 à 3 μm de long etdistantes d’environ 60 μm. Il s’agit de la première mise en évidence d’une hétérogénéité de structure de lasoie. Le couplage avec la traction uni-axiale montre une sollicitation de ces régions ordonnées sousdéformation, suggérant une organisation de la soie selon le modèle de Prevorsek, c’est à dire qu’une mêmechaîne macromoléculaire appartient à la fois à des régions amorphes et à des régions ordonnées. L’étudestatistique des propriétés mécaniques de la soie de ver et d’araignée montre une grande distribution, maisune bonne stabilité dans le temps (dizaines d’années). La modification génétique ne procure pasd’amélioration des propriétés mécaniques de la fibre, seulement une légère diminution de la variabilité.Diverses stratégies sont mises en oeuvre pour tenter d’échapper à cette variabilité : production bactérienne,solubilisation de la soie et régénération sous forme de films. Le rôle de l’eau lors de la biosynthèse de lasoie, ainsi que l’effet de divers paramètres (filtration, pH, séchage…) lors de la préparation des films ont étéétudiés. Nous avons pu confirmer que la présence d’agrégats de protéines favorise l’organisation dans lesfilms et 2 types de films ont donc été préparés. Les films les plus amorphes présentent les propriétésmécaniques les plus intéressantes, même si elles n’atteignent de quelques % de celles des fibres. Lafabrication de composites à matrice de soie régénérée renforcée par des fibres de soie permet d’augmenterla résistance et la déformation à rupture. Ces premiers résultats sont encourageants pour le développementde matériaux composites fibres de soie/matrice de soie régénérée<br>Fibrous proteins (keratin, elastin, collagen, fibroin ...) make up to one third of the proteins ofmammals and birds. They are structural proteins with a protective and/or mechanical function. Silk appearsto be the ‘simplest’ model because it mainly consists of two small amino acids residues (alanine andglycine). Some silks have comparable or superior mechanical properties compared to those of syntheticfibres and could be used in technical applications (e.g. biomedical) if the variability of their properties canbe controlled. This work focuses on the structure of silks from: Bombyx mori (domestic silkworm)degummed or not, Nephila madagascariensis (wild spider, no sericin coating), GM Bombyx mori (includinga gene of Nephila) a recombinant spider silk 4RepCT (Escherichia Coli). Silk is analyzed by Ramanspectroscopy (and FTIR), uni-axial tensile testing, and also by the coupling of these methods. The analysisof the low wavenumbers region in Raman spectroscopy allowed the characterization of ordered regions of 2to 3 microns separated by about 60 microns. This is the first evidence of the heterogeneous structure ofsilk. Coupling with the uni-axial tensile test shows that these ordered regions are stressed under macroscopicdeformation, suggesting silk organization according to Prevorsek’s model, i.e. that the samemacromolecular chain belongs to both amorphous and ordered regions. The statistical study of themechanical properties of silkworm and spider silks shows great dispersion, but a good stability over time(decades). Genetic modification does not improve the fibres mechanical properties but a slight decrease intheir variability. Various strategies have been investigated to control the variability: bacterial production,solubilization of silk and films regeneration. The role of water in silk biosynthesis, as well as the effect ofvarious parameters (filtration, pH, drying ...) during the preparation of the films were studied. It wasconfirmed that the presence of protein aggregates promotes the organization in film and two types of filmswere prepared. The most amorphous ones have the most interesting mechanical properties, though only afew percent of those from the starting fibres. The fabrication of regenerated silk matrix compositesreinforced by silk fibres increases the strength and strain to failure. These initial results are encouraging forthe development of silk fibres/regenerated silk matrix composite materials
6
Zhang, Jie. "Contribution aux développements des technologies de compression polymères chargés pour la réalisation d'inserts métalliques micro-structurés." Thesis, Besançon, 2013. http://www.theses.fr/2013BESA2044/document.
Full textAbstract:
Les travaux menés dans le cadre de cette thèse sont focalisés sur les procédés deréplication permettant la transformation des mélanges en composants par les technologiesen séquentiel ou bien en continu, selon les applications visées. Les développementsconcernent la mise en place et l’hybridation de différents procédés de micro-réplication(estampage à chaud de polymère thermoplastique et par laminage circulaire entre deuxrouleaux). Ces deux procédés sont développés et optimisés pour l’élaboration decomposants micro-structurés ou de microcomposants possédant des propriétésfonctionnelles mécaniques ou thermo-physiques requises à partir de différents mélangeschargés en poudres métalliques ou en nanotubes de carbone. Des exemples de réalisationde composants structurés, à base d’un système micro-fluidique possédant plusieurs canauxde 200 microns par 200 microns et des réservoirs de diamètre de 2 mm, sont prises commeexemple tout au long de ces travaux de cette thèse. Différents travaux de caractérisationsont été entrepris pour optimiser les procédés de micro-réplication par estampage à chaud etpar laminage circulaire entre deux rouleaux<br>The Ph.D subject concerns the study of two micro-replication processes by hotembossing and roll to roll processes for thermoplastic polymers and loaded polymers withpowders or carbon nanotubes. The micro-replication processes, realized in sequential orcontinuous ways, use some different elaborated loaded feedstocks in order to obtainstructural components or micro-component with high aspect ratio and mechanical orthermo-physical properties.A chain combining hot embossing and roll embossing and powder metallurgy have beendeveloped in our lab and investigated. The different micro mould die cavities have beenrealized with different micro-manufacturing process, elastomeric mould has been obtainedby casting process. Finally, a metallic structured die cavity has been obtained by combininghot embossing and debinding and sintering stages. The second topic is the comparison ofmetallic die cavity mould obtained by roll embossing or rolls embossing. Two demonstratorshave been developed during the preparation of this Ph.D period: first a metallic micro-fluidicsystem with micro-structuration with diameter of 1 mm for the reservoir and 200 microns by200 microns for the channel have been realized and characterized by different methods.Secondly, some functional micro-component has been obtained with carbon nanotube andsome specific properties in terms of mechanic and thermo-physical properties have beencharacterized
7
Pacchini, Sebastien. "Etude des potentialités des nanotubes de carbone dans le domaine hyperfréquence : Application à l'élaboration de matériaux nanocomposites et contribution à la miniaturisation de composants électromécaniques (NEMS)." Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00366700.
Full textAbstract:
La découverte des nanotubes de carbone (NTCs) par S.Iijima en 1990 a permis d'explorer un nouveau monde à l'échelle nanométrique. Les études sur la synthèse des NTCs durant le début de cette décennie ont apporté une reproductibilité des formes allotropiques de carbone. Les propriétés mécaniques et électriques exceptionnelles des NTCs ont éveillé l'esprit des scientifiques afin de concevoir des systèmes touchant le domaine de la nanotechnologie. Dans ce contexte, mes travaux de recherches ont visé à étudier les potentialités des nanotubes de carbone dans le domaine des hyperfréquences. Deux types d'applications peuvent être distinguées : l'élaboration de matériau nano-composite mais aussi la miniaturisation des composants électromécaniques (NEMS). L'application la plus immédiate des NTCs consiste à les utiliser comme additif dans des polymères, thermoplastiques, thermodurcissables ou élastomères, afin d'en modifier les propriétés. L'utilisation des matériaux composites à base de nanotubes de carbone apparaît comme une voie prometteuse dans le domaine des nanotechnologies grâce à leurs propriétés structurales et électroniques très particulières. Pour élargir le domaine d'application des NTCs, nous avons étudié un nouveau matériau composite à base d'un polymère (BenzoCycloButène BCB'') et de nanotubes de carbone double parois (DNTCs) pour une utilisation aux fréquences micro-ondes. Nous rapportons ici une étude des propriétés micro-ondes de composites BCB/DNTCs en fonction de la concentration massique de nanotubes. Nous présentons, dans un premier temps, les méthodes d'homogénéisation et de fabrication du composite, puis nous traitons l'élaboration de structures de test adaptées à des mesures µondes et millimétriques. Après caractérisation, nous donnons le comportement spectral et la modélisation pour les pertes linéiques ainsi que e* (permittivité effective complexe). Cette étude a permis de montrer qu'il est possible de configurer les performances électriques d'un matériau composite en fonction du % de NTCs incorporés. Ceci peut permettre de réaliser des matériaux absorbants d'ondes électromagnétiques pour la microélectronique. Une autre possibilité d'utilisation est d'exploiter les propriétés physiques ainsi que dimensionnelles des NTCs pour étendre le concept de composants passifs reconfigurables et micrométriques (MEMS) à l'échelle nanométrique avec l'élaboration de Système Nano-Electro- Mécaniques (NEMS). Leurs dimensions nanométriques permettraient de concevoir de futurs dispositifs électroniques fortement miniaturisés. Nous nous sommes donc intéressés au développement d'une filière technologique d'interconnexions pour réaliser une capacité variable dont la partie mobile est réalisée à l'aide de NTCs. Plusieurs voies ont été étudiées. Une 1ère comporte la croissance localisée des NTCs, réalisée à 600°C minimum par le LPICM. Cette température a impliqué de nombreux choix quant à la filière d'interconnexions (procédés chauds-froids suivant le positionnement de l'étape de croissance des NTCs) et d'études de compatibilité thermique. Une seconde voie est basée sur l'emploie de film mince de NTCs dispersés aléatoirement.- Au final, cette étude représente une grande avancée vers l'élaboration de NEMS RF à base de NTCs.
8
Peng, Suili. "Nano/micro particle-based functional composites and applications /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?NSNT%202007%20PENG.
Full text
9
Peters, Sarah June. "Fracture Toughness Investigations of Micro and Nano Cellulose Fiber Reinforced Ultra High Performance Concrete." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/PetersSJ2009.pdf.
Full text
10
Peditto, Francesca Priola Aldo Gérard Jean-François. "Photopolymerized micro-and nano-composites interface chemistry and its role on interfacial adhesion /." Villeurbanne : Doc'INSA, 2005. http://docinsa.insa-lyon.fr/these/pont.php?id=peditto.
Full text
11
Jordan, Jeff. "Composites at micro- and nano-scale and a new approach to the problem of a concentrated force on a half-plane." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/16431.
Full text
12
Banishev, A. A., A. A. Lotin, and A. F. Banishev. "Deformation Stimulated Luminescence of Nano-micro-parcticles SrAl2O4:(Eu2+, Dy3+) in a Matrix of Photopolymer and Creation of Sensor Elements of Mechanical Stresses." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35389.
Full textAbstract:
The work deals with low-temperature photoluminescence and deformation luminescence (mechanolu-minescence) of a composite material based on fine disperse powder of phosphor SrAl2O4:(Eu2+, Dy3+) and photopolymerizing resin that is transparent in the visible region. It has been shown that at the low tem-perature (T=15÷200 K) the photoluminescence spectrum of SrAl2O4:(Eu2+, Dy3+) displays two wide, partial-ly overlapping bands with the maxima at λ1max517 nm and λ2max446 nm. The short-wave luminescence band (λ2max446 nm) has been found to undergo temperature quenching and to completely decay at T200 K. A mechanism of mechanoluminescence excitation has been suggested. It has been shown that the com-posite material exhibits high sensitivity to mechanical action.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35389
13
Ladj, Rachid. "Elaboration de nanoparticule composite à propriétés optiques non-linéaires pour applications biomédicales." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENA032.
Full textAbstract:
Des marqueurs biologiques exogènes à base de nanoparticules hybrides possédant des propriétés optiques non-linéaires ont été préparés en tant qu'agent de contraste pour l'imagerie de second harmonique et le diagnostic de cellules pathogènes. L'iodate de fer est l'un des matériaux proposés dans ce domaine en raison de ses bonnes propriétés de second harmonique et de sa faible toxicité. Des nanoparticules d'iodate de fer ont été synthétisées par microémulsion inverse et miniémulsion inverse. Un bon contrôle de taille et de morphologie des particules a été obtenu dans les deux cas. En vue d'applications biomédicales, l'encapsulation des particules a été réalisée in situ par polymérisation en miniémulsion inverse. Enfin, l'encapsulation de particules de niobate de potassium par un polymère biocompatible a été étudiée. L'intérêt de ces particules hybrides a été démontré par des études in vitro en imagerie de second harmonique<br>Exogenous biomarkers based on hybrid nanoparticles with nonlinear optical properties were prepared as a contrast agent for second harmonic imaging and diagnosis of pathogenic cells. Iron iodate is one of the selected materials for this specific field due to its good second harmonic properties and its low toxicity. Iron iodate nanoparticles were synthesized by inverse microemulsion and inverse miniemulsion. In both cases, a good control of size and morphology was achieved. For biomedical applications, nanoparticles encapsulation was carried out in situ by reverse miniemulsion polymerization. Finally, encapsulation of potassium niobate nanoparticles with a biocompatible polymer was conducted. Their interest was demonstrated in vitro by second harmonic imaging studies
14
Mokhtari, Morgane. "FeCr composites : from metal/metal to metal/polymer via micro/nano metallic foam, exploitation of liquid metal dealloying process." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI088/document.
Full textAbstract:
Les métaux micro ou nanoporeux sont très attrayants notamment pour leur grande surface spécifique. Le désalliage dans un bain de métal liquide permet une dissolution sélective d'une espèce chimique (l'élément soluble) à partir d'un alliage d'origine (le précurseur) composé de l'élément soluble et d'un élément cible (qui deviendra nano/micro poreux) non soluble dans le bain de métal liquide. Quand le précurseur est plongé dans le bain de métal liquide, à son contact, l'élément soluble va se dissoudre dans le bain tandis que l'élément cible va en parallèle se réorganiser spontanément afin de former une structure poreuse. Quand l'échantillon est retiré du bain, il est sous la forme d'une structure bi-continue composée de deux phases : l'une étant la structure poreuse composée de l'élément cible et l'autre est une phase dans laquelle est présente l'élément du bain avec l'élément sacrificiel en solution solide. Cette phase peut être dissoute par une attaque chimique afin d’obtenir le métal nano/micro poreux. Les objectifs principaux de cette thèse sont l'élaboration et la caractérisation microstructurale et mécanique de 3 différents types de matériaux par désalliage dans un bain de métal liquide : des composites métal-métal (FeCr-Mg), des métaux poreux (FeCr) et des composites métal-polymère (FeCr-matrice époxy). Le dernier objectif est l'évaluation des possibilités d'utiliser la technique de désalliage dans un bain de métal liquide dans un contexte industriel. L'étude de la microstructure est basée sur des observations 3D faites par tomographie aux rayons X et des analyses 2D réalisées en microscopie électronique (SEM, EDX, EBSD). Pour mieux comprendre le désalliage, le procédé a été suivi in situ en tomographie aux rayons X et diffraction. Enfin, les propriétés mécaniques ont été évaluées par nanoindentation et compression<br>Nanoporous metals have attracted considerable attention for their excellent functional properties. The first developed technique used to prepare such nanoporous noble metals is dealloying in aqueous solution. Porous structures with less noble metals such as Ti or Fe are highly desired for various applications including energy-harvesting devices. The less noble metals, unstable in aqueous solution, are oxidized immediately when they contact water at a given potential so aqueous dealloying is only possible for noble metals. To overcome this limitation, a new dealloying method using a metallic melt instead of aqueous solution was developed. Liquid metal dealloying is a selective dissolution phenomenon of a mono-phase alloy solid precursor: one component (referred as soluble component) being soluble in the metallic melt while the other (referred as targeted component) is not. When the solid precursor contacts the metallic melt, only atoms of the soluble component dissolve into the melt inducing a spontaneously organized bi-continuous structure (targeted+sacrificial phases), at a microstructure level. This sacrificial phase can finally be removed by chemical etching to obtain the final nanoporous materials. Because this is a water-free process, it has enabled the preparation of nanoporous structures in less noble metals such as Ti, Si, Fe, Nb, Co and Cr. The objectives of this study are the fabrication and the microstructure and mechanical characterization of 3 different types of materials by dealloying process : (i) metal/metal composites (FeCr-Mg), (ii) porous metal (FeCr) (iii) metal/polymer composites (FeCr-epoxy resin). The last objective is the evaluation of the possibilities to apply liquid metal dealloying in an industrial context. The microstructure study was based on 3D observation by X-ray tomography and 2D analysis with electron microscopy (SEM, SEM-EDX, SEM-EBSD). To have a better understanding of the dealloying, the process was followed in situ by X-ray tomography and X-ray diffraction. Finally the mechanical properties were evaluated by nanoindentation and compression
15
永正, 邵., and Yongzheng Shao. "Study on the effects of matrix properties on the mechanical properties of carbon fiber reinforced plastic composites." Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB12902982/?lang=0, 2015. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB12902982/?lang=0.
Full textAbstract:
It was found that a significant improvement of mechanical properties of CFRPs can be achieved by the adjustment of the matrix properties such as toughness and CF/matrix adhesion via the chemical modification, as well as the physical modification by a small amount of cheap and environment-friendly nano fibers. Based on investigation of fracture mechanisms at macro/micro scale, the effects of matrix properties and nano fiber on the mechanical properties of CFRP have been discussed. Subsequently, the relationship has been characterized by a numerical model to show how to modulate the parameters of the matrix properties to achieve excellent fatigue properties of CFRP.<br>博士(工学)<br>Doctor of Philosophy in Engineering<br>同志社大学<br>Doshisha University
16
Wang, Sih Han, and 王思涵. "Magnetic Behavior Analysis of Magnetic Composite Nano/Micro Structure." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/09708299442991158342.
Full text
17
Tseng, Kuo-Tung, and 曾國棟. "Laser 3D printing technology for micro / nano composite structure." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/bkvmm8.
Full textAbstract:
碩士<br>中原大學<br>機械工程研究所<br>106<br>This thesis proposed a method to create molds with hierarchical micro/nano structures to enable the imprinting of conductive polymer polyaniline (PANI) for use as an electrode.The microstructure of mold was made by 3D printing. Computer-aided software (AutoCAD) was used to draw square column structures with micrometer size, and self-made 3D printer was used to fabricate micro-columns. Then the laser interference lithography was employed to build nanostructure on the surface of the micro-columns to form hierarchical micro/nano structures. Polydimethylsiloxane (PDMS) was used as a soft mold to duplicate the pattern of the previous hard mold. At last, PANI solution was poured into PDMS mold, then heat up to fabricate PANI solidified film applied in the supercapacitor.
Using field emission scanning electron microscope (FE-SEM) confirmed that the surface structure of the film identification. On a three-electrode electrochemical cell, experiments were performed to characterize the electrochemical properties of plane PANI and PANI with microstructure and hierarchical microstructure, respectively. Cyclic voltammetric (CV), galvanostatic charge–discharge, and electrochemical impedance spectroscopy (EIS) measurements were then conducted using 1M H2SO4 as an electrolytic solution. Experimental results demonstrated that its specific capacity was 487 F/g, which is higher approximately 60% compared with PANI plane film. Increasing the surface area of PANI through the inclusion of hierarchical structures enhanced oxidation/reduction reactions, leading to a higher average specific capacitance.
18
LEE, Tung-Yuan, and 李東原. "A Flexible Micro-PEMFC Electrodes of composite Polydimethylsiloxane(PDMS) Nano/Microstructures." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/88182798435113958462.
Full textAbstract:
碩士<br>國立清華大學<br>工程與系統科學系<br>102<br>In this paper, a novel design of PDMS-based bendable electrodes with microstructures is proposed for flexible proton exchange membrane fuel cells (PEMFCs). The design of the bendable electrodes incorporates micro-structured PDMS-film to increase the reaction area and fuel pass-way, conducting layer Au with strong conjugation to the PDMS-microstructures for electron conduction, and Pt catalyst for fuel reaction.
The electrodes perform ISO class 0 in adhesion test and only increase 6.6% resistance under 2/cm bending curvature. The half-cell test yields a performance of 12.7~13.8mA/cm-2 at 0.6V under serious bending conditions and also 2.55mW/cm2 at 0.321V in fuel cell test.
19
Tsai, Shin-Jae, and 蔡欣潔. "Preparation and study of physical properties of epoxy micro/nano composite." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/15777480972397651329.
Full textAbstract:
碩士<br>國立高雄應用科技大學<br>化學工程與材料工程系<br>97<br>This research is mainly divided into two parts: First, multi-wall carbon nanotubes (MWNTs) were synthesized by arc discharged method and it also studies the influences of the intensity of electricity and gas flow rates on the quality and yields of MWNTs. Moreover, carbon nanotubes were purified by chemical vapor phase oxidation. The structures and qualities of MWNTs were characterized by transmission electron microscope (TEM), field emission scanning electrical microscope (FE-SEM), fourier transform infrared spectrum (FTIR), and Raman spectroscopy. The results showed that the synthesized MWNTs are ranging in number five to dozens. The highest yield of MWNTs was obtained from gas flow rate at 2.5 L/min and the intensity of electricity at 120A, and the best crystalinity and purity of MWNTs were obtained from gas flow rate at 7.5 L/min and the intensity of electricity at 100A. The amorphous carbonaceous were decreasing after being purified by nitric acid oxidation.
In the second part, the epoxy micro/nano composites were prepared by epoxy resins with various inorganic materials such as self-synthesized MWNTs, vapor grown carbon fiber (VGCF), aluminum nitride and aluminum oxide. The curing behavior of curable resins were studied by differential scanning calorimeter (DSC) and the properties of cured resins were studies by FE-SEM, dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA) and thermal conductivity meter. The result showed that the more filler were added, the better dispersion in the resins. The glass transition temperature (Tg) and char yield were increased by increase filler contents. The thermal conductivity of high aspect ratio MWNTs and VGCF which contained 70% filler were obvious than filler of aluminum nitride and aluminum oxide. Moreover, a thermal conductivity of 6.276 W/mK was obtained when carbon fiber fillers content up to 70%.
20
Yew, Hsu Zenn. "Colour changes in nano-filled and micro-hybrid composite resins on exposure to spices." Thesis, 2012. http://hdl.handle.net/2440/73307.
Full textAbstract:
Colour changes in composite resins after immersion in beverages such as coffee, tea, alcohol beverage and carbonated drinks have been reported. Although much work has been done to determine the staining susceptibility of composite resins to various liquid beverages, effects of spices on colour stability of composite resins have not been fully researched.
Objectives: The aim of this study is to evaluate the colour stability of nano-filled (Filtek Supreme™) and micro-hybrid (Gradia Direct™) composite resins finished with either Sof-Lex™ discs or mylar strips upon exposure to turmeric, paprika and tamarind.
Materials and methods: Twenty cylindrical specimens were fabricated from two commercially available composite resins; Filtek Supreme XT™ (3M ESPE, St Paul, MN) and Gradia Direct X™(GC AMERICA). The top surfaces of the specimen were polished with Sof–Lex™ aluminium oxide discs (3M/ESPE, St Paul, MN USA) while the bottom surfaces were mylar strips finished. All samples were subjected to 500 thermocycling rounds between 5 and 55 ºC with 20 seconds dwell time prior to immersion in staining solution. Twenty specimens from each type of composite were then randomly divided into 4 groups (n=5) and immersed in each staining solutions (0.1% turmeric, paprika and tamarind) and distilled water (control) at 37 ºC. Colour measurement at baseline, after thermocycling, 24 hours (1 day), 72 hours (3 days) and 168 hours (7 days) of immersion in staining solutions were recorded with a reflection spectrophotometer under the D65 (daylight) illuminant using CIE L* a* b* parameters. Repeated measures analysis of variance (ANOVA) and Bonferroni post hoc tests were used to determine the significance and possible interactions of each factor.
Results: Among all the staining solutions tested, the highest colour deviation was obtained in the turmeric group, with mean colour change (ΔE) ranging between 17.92 and 55.25. Paprika recorded mean colour change (ΔE) ranging between 1.28 and 3.72, while tamarind produced mean colour change (ΔE) ranging between 1.12 and 5.42. The effect of finishing method on colour stability of composite resins appeared to be dependent on the type of composite resin. Filtek Supreme™ with mylar strips finished generally resulted in significantly more colour changes compared with specimens polished Sof-Lex™ discs, while Gradia Direct™ finished with mylar strips were found to be more resistant to colour changes. Colour change (ΔE) values were significantly influenced by the staining solutions, types of materials and finishing methods.
Conclusion: Within the limitations of this study, all spices used (turmeric, paprika and tamarind) have a potential to stain composite resins; with turmeric causing the most severe discolouration regardless of the type of composite resin or finishing technique employed. The result of this study also suggests that different materials respond differently to staining by spices when either finished with mylar strips or polished with Sof-Lex™ discs. Also, contemporary composite resins available in the market e.g. nano-composite and micro-filled hybrid composite are still susceptible to discolouration by exogenous factors despite advancement in the development of resin based restorative material.<br>Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2012
21
Yen, Jia-Hong, and 顏家宏. "Research on the micro friction of the Nano Aluminium Oxide / Polymethyl Methacrylate Composite." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/05969698262827366777.
Full textAbstract:
碩士<br>雲林科技大學<br>機械工程系碩士班<br>96<br>In the thesis, the nano composite containing PMMA matrix and nano Al2O3 are produced in three weight ratios ( 1%、3%、5%); the specimen having coated Al2O3 layer on pure PMMA are prepared as well. Then the nano scratch tribometer is used for the friction coefficient tests under different loadings and scratch velocities. In addition, the commercial code ABAQUS is employed to validate the experimental results.
It can be seen from the experiments that the friction coefficient is reduced by adding the nano Al2O3 to the PMMA and the test with coated Al2O3 layer yields the lowest friction coefficient. By measuring the surface topography with white light interferemeter, we find that the 3% Al2O3 sample possesses the smallest scratch depth. This finding concurs with the fact that the 3% Al2O3 specimen demonstrates the highest Vicker’s hardness, which leads to the lowest scratch depth. The scratch becomes shallow, thus the lower friction coefficient, in the cases of high velocity than that in the low velocity, and is believed to result from the viscous (strain rate) nature of the material. This surmise is verified by the numerical simulations where the tendency of decreasing the scratch depth is obtained as the simulated velocity is enhanced.
22
WU, YI-ZHE, and 吳易哲. "The Study of Fabrication Black Silicon Solar Cells With Micro / Nano Composite Structures." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/puwvb8.
Full textAbstract:
碩士<br>國立雲林科技大學<br>電子工程系<br>106<br>In This study demonstrates on the suppression of light reflection by nanostructures, and application to solar cells as anti-reflection. The characteristics of the pyramidal structure combined with the nanowire etching for surface reflectivity are discussed, Make use of phosphoric acid as n-type diffusion source with spin coating method to manufacture p-n junction, to achieve the goal of cost down.
In this experiment have a minimum reflectance of 3.2% by electroless etching for 60s, after thermal annealing at 400℃, the reflectivity drops to 2.9%, Pyramid structure combined with nanowire etching. Silver film deposited by magnetron sputtering has a minimum reflectivity of 2.5%. The electrical characteristic diffusion temperature of the p-n junction has the best electrical characteristics at 930 °C and the time at 20 min.
23
Tsai, Ming-Qun, and 蔡名琨. "A study on the fabrication and properties analysis of SiC/C micro-nano composite films." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/92349229617432323372.
Full textAbstract:
碩士<br>國立成功大學<br>機械工程學系碩博士班<br>92<br>The layer-by-layer carbon/silicon micro-nanocomposite films are deposited by ultra high vacuum ion beam sputtering system (UHV IBS) under different substrate temperature or at room temperature together with post vacuum annealing. The relations between deposition procedures, composition, micro-nano structure, temperature and mechanical properties are established after process and material analysis in this thesis. They are potentially used in the application of the surface modification of precision mechanics or micro electromechanical devices. The experiments are divided into two parts of single layer film and carbon/silicon multilayer film.
The results of deposition rate calibration show that the deposition rate of silicon film is higher than carbon film. The reason is the bonding strength of carbon higher than silicon. 40 nm carbon films deposited on silicon wafers at different temperatures are used to study the substrate’s temperature effect on the reaction of carbon to silicon. The results show the DLC begins to form nanocrystalline graphite (“glassy” carbon) when temperature increases. When substrate’s temperature is at 600 ℃, the carbon film begins to form silicon carbide. And when substrate’s temperature increases to 700℃, carbon and silicon react completely and the its topography is smooth. In addition, carbon/silicon micro-nanocomposite films were deposited at room temperature and then done by a series of post vacuum annealing to study the relation between films’ structure and mechanical properties at varied vacuum annealing temperature.
Two kinds of layer-by-layer films were prepared. First, single carbon film and two-layers carbon/silicon composite film were annealed at the same temperature and different time to study the relations of the structure and mechanical properties. The results show that the hardness of single carbon film is higher than two-layers carbon/silicon composite film due to the higher hardness of carbon film than silicon film. Both of the films decrease their hardness a little when annealing time increases. The reason is that carbon film is easy to graphitize at high temperature with increasing time. Second, three-layers carbon/silicon [a] composite films (Si/C/Si=50/200/50 nm), three-layers carbon/silicon [b] composite films (Si/C/Si=75/150/75 nm) and five-layers carbon/silicon composite films (Si/C/Si/C/Si=30/105/30/105/30 nm) were annealed at different temperature with the same time to study the relations of structure and mechanical properties. The results show the hardness is to increase when vacuum annealing temperature keeps at 700℃. The may be caused by the appearance of silicon carbide at 700℃. When vacuum annealing temperature increase to 900℃, the roughness of three-layers and five-layers carbon/silicon composite films increase obviously. It is caused by more crystallization of Si films in the multilayers at high temperature. The hardness of five-layer carbon/silicon composite films (Si/C/Si/C/Si=30/105/30/105/30 nm) and three-layers [a] carbon/silicon composite films (Si/C/Si=50/200/50 nm) are higher than three-layers [b] carbon/silicon composite films (Si/C/Si=75/150/75 nm). This is due to the total amount of carbon film and silicon film in the multilayer. In addition, the elastic modulus of five-layer carbon/silicon composite films is higher than three-layer carbon/silicon composite films to enhance the stiffness of materials. It is possible to promote the mechanical properties using multilayer composite structure by controlling the layer thickness and number.
24
LIN, WEN-ZHONG, and 林文中. "The Influence of Micro and Nano Fillers on the Thermal Properties of Polymer Composite Films." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/tf9kdj.
Full textAbstract:
碩士<br>國立虎尾科技大學<br>光電工程系光電與材料科技碩士班<br>106<br>The size of electronic products is becoming smaller and lighter and easier to carry today, but the computing power of the core processor is growing day by day. The heat generated from the CPU is likely to cause high temperature in the device. The performance, stability, lifespan, and user comfortability of electronic products could be reduced and even cause shot down of the system, since the thermal released from the CPU is accumulated quickly and difficult to dissipate from the electronic device. Therefore, how to remove the derived heat away from the heat source to avoid accumulation becomes quite important. In this study, we combined the electronic and phononic heat transfer mechanisms to increase the thermal conductivity of the composite coating films by filling a conductive polymer PEDOT between the BN, AlN, SiC micro-nano ceramic fillers gap. The heat is radiated from the surface of the composite films due to the high infrared emissivity fillers were connected by the conductive polymer. The highest thermal conductivity and the infrared emissivity of the composite coating can achieve 148.66 (W/M∙K) and 0.977, respectively. The results of this study also could be applied to the devices that are lightweight, fan-free or energy-efficient required devices in the future.
25
Yeh, Chun-Hung, and 葉俊宏. "Preparation of Micro/Nano Composite Powder Using Mechanofusion Technique and Its Application for Dye-Sensitized Solar Cells to Promote Conversion Efficiency." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/35485727910355480115.
Full textAbstract:
碩士<br>國立屏東科技大學<br>機械工程系所<br>95<br>This study designed and fabricated a sandwich TiO2 thin-film electrode for a dye-sensitized solar cell which contained a nanocrystalline TiO2 layer that was sandwiched between an ITO substrate and a layer of micro/nano TiO2/dye composite particles. Furthermore, the study investigated the effect of the sintering temperature and dispersants on the performance of a dye-sensitized solar cell (DSSC). A dry particle coating technique was performed to coat the powder of the CuPc dye (copper phthalocyanine, CuPc, C32H16CuN8) on the surface of the TiO2 powder. The coating was done by means of the Mechanofusion System. A nanocrystalline TiO2 layer and a layer of micro/nano TiO2/dye composite particles were subsequently fabricated in that order on the ITO substrate using the doctor blade technique. The BET surface area of the micro/nano TiO2/dye composite particles in the rotation speed of the rotating chamber was 3000 rpm as the mass of the CuPc dye powder increased from 1g to 2g, the BET surface area of the micro/nano TiO2/dye composite particles fell from 43.71 m2/g to 38.5 m2/g. Additionally, the CuPc dye powder mass was 2 g; as the rate of rotation of the chamber increased from 3,000 to 6,000 rpm, the BET surface area of the micro/nano TiO2/dye composite particles increased slightly from 38.5 m2/g to 39.39 m2/g. The dispersant of the TiO2 thin-film was alcohol and the sintering temperature was 450 ℃ in the dye-sensitized solar cell. This layer of micro/nano TiO2/dye composite particles (TiO2 and CuPc dye mass ratio was 9:2 g; the rotation speed of the rotating chamber was 6000 rpm) markedly increased the short-circuit photocurrent from 9.56 μA(conventional DSSC) to 15.59 μA(DSSC with a layer of micro/nano TiO2/dye composite particles). Nevertheless, this layer of micro/nano TiO2/dye composite particles increased the open-circuit photo-voltage from 0.09 V (conventional DSSC) to 0.48 V (DSSC with a layer of TiO2/dye composite particles).
26
Hsu, Sheng-Chieh, and 徐聖傑. "Comparative studies on the Preparation Preparation and Physical Properties of Environmentally Friendly PMMA-silica Nano/Sub-micron Scaled Composite Latexs Controlled by Chelating Agent." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/xk5y2j.
Full textAbstract:
碩士<br>中原大學<br>化學研究所<br>98<br>In this paper, comparative studies on the preparation and physical properties of as-prepared PMMA/nano-silica composite (PNS) and PMMA/Submicro-silica composite (PMS) materials were successfully presented. Vinyl-modified silica nanoparticles and sub-microparticles were first prepared by sol-gel route with/without chelating agent of acetyl acetone (AcAc). Specific feeding amount of silica particles was subsequently reacted with MMA monomers by emulsion polymerization to yield series of PMS and corresponding PNS materials, respectively.
Systematically comparative studies on the physical properties of both as-prepared composite materials indicated precisely that PNS showed effectively enhanced anticorrosion, mechanical properties as compared to that of corresponding PMS based on a series of instrumentation evaluations performed by electrochemical cyclic voltammetric (CV), Salt Spray Test, dynamic mechanical analysis (DMA), Gas Permeability Analyzer (GPA), Vapor Permeability Analyzer (VPA) and UV-visible transmission spectroscopy, respectively.