Tesis: "PMMA copolymers"

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CAVALCANTE, JONAS S. "Caracterizacao de copolimero reticulado, a base de acrilato e metacrilato obtido por fotopolimerizacao para aplicacao como guia de onda". reponame:Repositório Institucional do IPEN, 2005. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11396.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Bier, Frédéric. "Conception et synthèse d’une matrice polymère thermoplastique pour l’obtention de matériaux composites recyclables, résistants au feu et utilisables dans l’industrie". Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0040.

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De nouvelles matrices thermoplastiques à base de poly(méthacrylate de méthyle) (PMMA) pouvant entrer dans la composition de matériaux composites ont été synthétisées et caractérisées du point de vue de leur température de transition vitreuse (par calorimétrie différentielle à balayage) et de leur dégradation thermique (par analyse thermogravimétrique et par microcalorimétrie). La stratégie suivie était d’incorporer dans les chaînes de PMMA des unités de répétition comportant un groupement latéral phosphoré retardateur de flamme via une copolymérisation radicalaire du MMA avec un monomère phosphoré. Un ensemble de monomères phosphorés retardateurs de flamme ont été synthétisés à partir de l’oxyde de 9,10-dihydro-9-oxa-10-phosphaphenanthrène-10 (DOPO) en faisant varier la nature de la fonction polymérisable (styrénique, acrylique, méthacrylique), la nature de l’atome lié au phosphore (oxygène, carbone, azote) et la longueur du bras espaceur. Nous avons montré qu’en adaptant la structure et la quantité des unités de répétition phosphorées, la température de transition vitreuse du matériau était maintenue proche de celle du PMMA alors que la dégradation thermique des matériaux était déplacée vers de plus hautes températures. Comparativement les mélanges physiques de PMMA et de DOPO avec une même teneur en élément phosphore présentent une température de transition vitreuse significativement plus basse
Novel poly(methyl methacrylate) (PMMA) thermoplastic matrices which can be used in the elaboration of composite materials have been synthesized and characterized from the point of view of their glass transition temperature (by differential scanning calorimetry) and their thermal degradation (by thermogravimetric analysis and by pyrolysis combustion flow calorimetry). The strategy followed was to incorporate in the PMMA chains repeat units comprising a flame retardant phosphorous side group via a radical copolymerization of MMA with a phosphorus-containing monomer. A set of phosphorus-containing flame retardant monomers has been synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide (DOPO) by varying the nature of the polymerizable function (styrenic, acrylic, methacrylic), the nature of the atom bound to the phophore (oxygen, carbon, nitrogen) and the length of the spacer arm. We have shown that by adapting the structure and the quantity of the phosphorus repeating units, the glass transition temperature of the material was kept close to that of the PMMA while the thermal degradation of the materials was shifted to higher temperatures. Comparatively, physical blends of PMMA and DOPO with equivalent phosphorus contents exhibited significantly lower glass transition temperatures

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Genoyer, Julie. "Compatibilization of PMMA/PS blends by nanoparticles and block copolymers : effect on morphology and interfacial relaxation phenomena". Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10198/document.

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Ces travaux de thèse présentent une étude du mécanisme de compatibilisation induit par des nanoparticules d’argile dans les mélanges de polymères en utilisant la rhéologie. Pour cela, de la montmorillonite, la laponite et l’halloysite, modifiées ou non, ont été ajoutées à des mélanges PMMA/PS. Les résultats de rhéologie linéaire en cisaillement ont montré que le mécanisme de compatibilisation, particulièrement le phénomène de coalescence, dépendait beaucoup de la localisation des nanoparticules. La montmorillonite modifiée, présente à l’interface entre les polymères, est la plus efficace à inhiber la coalescence et est aussi efficace qu’un copolymère à bloc de haute masse molaire. Ceci est particulièrement intéressant car les nanoparticules d’argile représentent un coût moindre comparé aux copolymères à bloc. Dans ces travaux, une attention spéciale a été portée aux relaxations présentes dans les mélanges. En utilisant la rhéologie linéaire en cisaillement, un effet Marangoni a été mis en évidence pour la première fois dans le cas de nanoparticules d’argile modifiées présentes à l’interface. Enfin, les mélanges soumis à un flux élongationnel puis relaxation ont montré que la relaxation des gouttes de phase dispersée après une importante déformation était plus rapide par ajout d’argiles dispersées dans la matrice et ralentie par des argiles mieux dispersées soit à l’interface, soit dans l’ensemble du mélange
In this thesis, the compatibilization mechanism induced by clay nanoparticles in polymer blends was investigated using rheology. To do so, montmorillonite, laponite and halloysite, modified or not, were added to PMMA/PS blends. Linear shear rheology showed that the compatibilization mechanism, especially the coalescence phenomenon, was greatly influenced by the localization of clay nanoparticles. Modified montmorillonite, which was located at the interface, was shown to be the most efficient at inhibiting coalescence among clays and as efficient as a block copolymer with a high molecular mass. The latter is particularly interesting as nanoparticles are cheaper than block copolymers. In this work, special attention was given to relaxations happening in blends. Using linear shear rheology, Marangoni stresses due to a gradient in compatibilizer concentration at the interface was evidenced for the first time in the case of organically modified clay nanoparticles when located at the interface. Finally, submitting blends to elongational flow and subsequent relaxation showed that the relaxation of the droplets after high deformations was faster in the case of clays dispersed in the matrix and slowed down by the interfacial tension in the case of a better dispersion of clays at the interface or in the whole blend

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Ozlem, Gundogdu Suriye. "The Characterization Of Some Methacrylate And Acrylate Homopolymers, Copolymers And Fibers Via Direct Pyrolysis Mass Spectroscopy". Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615308/index.pdf.

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THE CHARACTERIZATION OF SOME METHACRYLATE AND ACRYLATE HOMOPOLYMERS, COPOLYMERS AND FIBERS VIA DIRECT PYROLYSIS MASS SPECTROSCOPY Ö
zlem Gü
ndogdu, Suriye Ph.D., Department of Polymer Science and Technology Supervisor: Prof. Dr. Jale Hacaloglu December 2012, 177 pages Poly(methyl methacrylate) possesses many desirable properties and is used in various areas. However, the relatively low glass transition temperature limits its applications in textile and optical-electronic industries. Monomers containing isobornyl, benzyl and butyl groups as the side chain are chosen to copolymerize with MMA to increase Tg and to obtain fibers with PMMA. In this work, thermal degradation characteristics, degradation products and mechanisms of methacrylate homopolymers, poly(methyl methacrylate), poly(butyl methacrylate), poly(isobornyl methacrylate) and poly(benzyl methacrylate), acrylate homopolymers, poly(n-butyl acrylate), poly(t-butyl acrylate), poly(isobornyl acrylate), two, three and four component copolymers of MMA and fibers are analyzed via direct pyrolysis mass spectrometry. The effects of substituents on the main and side chains, the components present in the copolymers and fiber formation on thermal stability, degradation characteristics and degradation mechanisms are investigated. According to the results obtained, the depolymerization mechanism yielding mainly the monomer is the main thermal decomposition route for the methacrylate polymers, acrylate polymers degradation occurs by H-transfer reactions from the main chain to the carbonyl groups. However, when the alkoxy group involves

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He, Guping. "The Effect of Modified AuNPs on the Morphology and Nanostructure Orientation of PPMA-b-PMMA Block Copolymer Thin Films". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-154391.

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Block copolymer/inorganic nanoparticle hybrids draw great attention of scientists from various areas for their potential applications in diverse fields such as microelectronics, sensors, and solar cells. Inorganic nanoparticles (NPs) can be expected to be incorporated into block copolymers with order and selectivity by self-assembly of NPs and/or by synergistic self-assembly between NPs and block copolymers. The morphology and nanostructure order of block copolymers can be also adjusted and directed by incorporation of NPs. In this study, the effect of the size and modification of AuNPs on the morphology and nanostructure orientation of block copolymer PPMA-b-PMMA thin films were systematically investigated. The lateral BCP structure in thin films was improved by adding AuNPs. The controlled location of AuNPs in the BCP thin films depended on the particle size and stabilizing species. The re-orientation of cylindrical domains depended on the modification of AuNPs. PPMA-coated AuNPs, corresponding to the lower surface energy component of BCP, were powerful in directing the cylinders from parallel to perpendicular to the substrate. These results provide a general guide for other BCP/inorganic NP hybrid systems for desired morphology and nanostructure orientation.

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6

Dupayage, Ludovic. "Élaboration contrôlée de glycopolymères amphiphiles à partir de polysaccharide : synthèse de Dextrane-g-PMMA par polymérisation radicalaire par transfert d'atome". Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL011N/document.

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De nouveaux glycopolymères amphiphiles en peigne de type dextrane-g-poly(méthacrylate de méthyle) ont été obtenus via une polymérisation radicalaire contrôlée par transfert d’atome (ATRP). Pour contrôler les paramètres macromoléculaires de ces glycopolymères potentiellement biocompatibles et en partie biodégradables, la stratégie de synthèse « grafting from » a été sélectionnée et appliquée selon deux voies de synthèse. La première voie comporte quatre étapes : acétylation partielle des fonctions hydroxyle du dextrane ; introduction des groupements amorceurs d’ATRP ; ATRP contrôlée du méthacrylate de méthyle dans le diméthylsulfoxyde ; hydrolyse des groupements acétate dans des conditions douces. La seconde voie de synthèse permet d’obtenir ces glycopolymères en seulement deux étapes : introduction directe des groupements amorceurs d’ATRP sur le dextrane ; ATRP contrôlée du méthacrylate de méthyle dans le diméthylsulfoxyde. Des études détaillées de chaque étape ont permis à la fois d’estimer la longueur de la chaîne de dextrane et d’assurer le contrôle de l’architecture des glycopolymères (nombre et longueur des greffons). Des études préliminaires par tensiométrie interfaciale ont permit d’évaluer le caractère tensioactif de ces glycopolymères
Synthesis of the new comb-like amphiphilic glycopolymer dextran-g-poly(methyl methacrylate) was obtained thanks to an Atom Transfert Radical Polymerization (ATRP). In order to control the macromolecular parameters of these biocompatible and partly biodegradable glycopolymers, the “grafting from” strategy was applied using two different multi-step pathways. The first one is composed of four steps: partial acetylation of dextran hydroxyl groups; introduction of initiator groups convenient for ATRP; ATRP of methyl methacrylate in dimethylsulfoxide; acetyl group deprotection under mild conditions. The second pathway allows us to obtain such glycopolymers in only two steps: direct introduction of the same initiator groups onto the dextran chain and subsequent ATRP of methyl methacrylate in dimethylsulfoxide. Throughout the synthesis, detailed studies of each step enabled us to estimate the length of the dextran backbone and to assure the control of copolymer architecture in terms of graft number and graft length. Preliminary interfacial tension measurements highlighted the surfactant properties of such glycopolymers

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Bézard, Philippe. "Développement de procédés de gravure plasma innovants pour les technologies sub-14 nm par couplage de la lithographie conventionnelle avec l'approche auto-alignée par copolymère à blocs". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT007/document.

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Le coût de la poursuite de la miniaturisation des transistors en-dessous de 14 nm demande l’introductionde techniques moins onéreuses comme l’approche auto-alignée par copolymères à blocs (DSA) combinéeà la lithographie 193 nm. Etudiée principalement pour des motifs de tranchées (pour les FinFETs)ou de cylindres verticaux (pour les trous de contact, c’est ce cas qui nous intéressera), le polystyrène-bpolyméthylmétacrylate(PS-b-PMMA) est un des copolymères à blocs les plus étudiés dans la littérature,et dont la gravure présente de nombreux défis dûs à la similarité chimique des deux blocs PS et PMMA.Proposer une solution à ces défis est l’objet de cette thèse.Dans notre cas où le PS est majoritaire, le principe est d’obtenir par auto-organisation des cylindresverticaux de PMMA dans un masque de PS. Le PMMA est ensuite retiré par solvant ou par plasma,les motifs ainsi révélés dans le PS peuvent être alors transférés en utilisant ce dernier comme masque degravure. Une couche de copolymères statistiques PS-r-PMMA neutralise les affinités du PS/PMMA avecle substrat et permet l’auto-organisation.Un des problèmes majeurs est le contrôle des dimensions ; traditionnellement, le PMMA est retiré paracide acétique et le PS-r-PMMA gravé par plasma d’Ar/O2 qui aggrandit le diamètre des trous (CD)en consommant lattéralement trop de PS. Des temps de recuit acceptables pour l’Industrie donnent ausommet du masque de PS une forme de champignon induisant une dispersion importante des diamètresmesurés (~4-5 nm).Nos travaux montrent que la dispersion de CD peut être corrigée par plasma en facettant le sommetdes motifs. Dans un premier temps, un procédé de retrait du PMMA par plasma continu de H2N2 a étédéveloppé afin de s’affranchir des problèmes induits par l’acide acétique et les plasmas à base d’O2. Cecia permis de révéler des défauts d’organisation non rapportés dans la littérature à notre connaissance : desfilms de PS de quelques nanomètres peuvent aléatoirement se trouver dans le domaine du PMMA et ainsibloquer la gravure de certains cylindres. Afin de graver ces défauts sans perdre le contrôle des dimensions,un procédé composé d’un bain d’acide acétique et d’un plasma synchronisé pulsé de H2N2 à faible rapportde cycle et à forte énergie de bombardement a été mis au point. Il permet de retirer le PMMA, facetterle sommet du PS (ce qui réduit la dispersion de CD à moins de 2 nm), graver les défauts et la couche deneutralisation tout en limitant l’agrandissement des trous à moins d’un nanomètre. La dernière difficultévient des dimensions agressives et du rapport d’aspect important des trous de contact gravés. Afin delimiter la gravure latérale et la consommation des masques, des couches de passivation sont déposées surles flancs des motifs pendant la gravure mais à des échelles inférieures à 15 nm, ces couches de quelquesnanomètres sont trop épaisses et nuisent au contrôle des dimensions. Les plasmas doivent être alors moinspolymérisants et la création d’oxydes sur les flancs par ajout d’O2 doit être évitée.Enfin, les techniques de détermination des dimensions à partir d’images SEM ne sont plus assezrobustes à ces échelles. Afin d’en améliorer la robustesse, des algorithmes de reconstruction d’image etd’anti-aliasing ont été implémentés
Shrinking transistor’s dimensions below 14 nm is so expensive that lower-cost complementary techniquessuch as Directed Self-Assembly (DSA) combined with 193 nm-lithography are currently beingdeveloped. Either organized as trenches for the FinFET’s fin or vertical cylinders for contact holes(which is our case study), Polystyrene-b-polymethylmetacrylate (PS-b-PMMA) is a well-studied blockcopolymer but introduces challenging etching issues due to the chemical similarities between the PS andPMMA blocks. The aim of this thesis is to overcome those etching challenges.In our case where PS is the dominant phase, the principle of DSA is to obtain through self-assemblya pattern of vertical cylinders of PMMA inside a mask constituted of PS. PMMA is then removed eitherby solvent or plasma, revealing the patterns in the PS mask, which will be used as an etching mask forpattern transfer. In order to allow self-assembly, a thin brush layer of random copolymers PS-r-PMMAis used to neutralize the affinity of each phase with the substrate.One of the main issues with DSA is the control of the dimensions (CD control): usually, PMMAis dissolved in acetic acid bath and the brush layer is etched by an Ar/O2 plasma which increasesdramatically the pore’s diameter (CD) by laterally etching the PS. Short duration of thermal annealingsuitable for the Industry induces some “mushroom” shape at the top of the mask which consequentlyincreases the measured CD dispersion (~ 4-5 nm).Our work shows that CD uniformity can be corrected by faceting the top of the patterns throughplasma etching. As a first step, a dry-etch process for PMMA based on H2N2 chemistry has beendeveloped in order to free ourselves from acetic-acid’s and O2-based plasma’s issues. As far as we know,the discovered kind of defects has never been reported in the literature: few nanometer-thick films madeof PS can randomly be found in the PMMA’s domain, thus delaying the etching of random cylinders. Inorder to etch those defects without loosing the CD control, an other process constituted of an acetic acidbath followed by a synchronously-pulsed H2N2 plasma at low duty cycle and high bias power has beendeveloped. This process removes PMMA, facets the top of the PS features (decreasing CD dispersionbelow 2 nm), etches both the defects mentionned above and the brush layer without increasing thepores’ diameters by more than one nanometer. One last etching challenge comes from the aggressivedimensions and the high aspect ratio of the contact holes. In order to limit the lateral etching and themask consumption overall, passivation’s layer are usually deposed on the sidewall of the features duringthe etching process, but at dimensions below 15 nm, those layers are too thick and cause a CD control lossthough they are only few-nanometer thick. The polymerization’s capacity of plasmas has to be loweredat this scale and oxidized layer’s formation by adding O2 to the plasma chemistry has to be avoided.Last but not least, the techniques based on SEM images to determine the pore’s dimensions are notrobust enough at those scales. In order to gain in robustness, image reconstruction and anti-aliasingalgorithm have been implemented

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Muzeau, Elisabeth. "Etude des relaxations mécaniques alpha et bêta du PMMA, du PS et de leurs copolymères". Lyon, INSA, 1992. http://www.theses.fr/1992ISAL0042.

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Les relaxations mécaniques alpha et bêta de polymères morphes ont été étudiées par spectrométrie mécanique dynamique dans le but de comprendre le rapport entre les propriétés mécanique dynamique et la structure chimique des systèmes. Pour cela, les matériaux poly(méthacrylate de méthyle) (PMMA) et polystyrène (PS) ont été choisis ainsi que des copolymères de ces deux systèmes. L'analyse des spectres de relaxation bêta du PMMA a permis d'attribuer la distribution des temps caractéristiques à une distribution très large du facteur entropique ainsi qu'une distribution plus étroite du facteur étroite du facteur énergétique. L'analyse de la relaxation bêta des copolymères a mis en évidence deux composantes, la première liée à la relaxation des unités MMA et la seconde attribuée à la relaxation des unités S. Les résultats expérimentaux de relaxation alpha des copolymères présentent une relaxation principale unique dont les caractéristiques se situent entre celles du PMMA et du PS. La relaxation alpha du PMMA s'étend jusqu'à des température basses. La relaxation alpha de tous les matériaux et les effets de vieillissement physique sur cette relaxation ont été analysés sur la base d'une théorie moléculaire des défauts quasi-ponctuels, développée au laboratoire. Cette théorie rend compte de l'ensemble des résultats expérimentaux en apportant une interprétation physique aux phénomènes observés dans ces polymères. Un tel travail met en évidence la relation entre le comportement mécanique et l'architecture moléculaire des polymères
The alpha and beta mechanical relaxations of amorphous polymers have been studied by dynamic mechanical spectrometry in order to understand the relation between the mechanical properties and the chemical structure of the systems. Poly(methyl methacrylate (PMMA), polystyrene (PS) and their copolymers were selected for this study. The analysis of the beta-relaxation spectra of PMMA enabled us to attribute the distribution of relaxation times to a very bread distribution of the activation entropy and a narrower distribution of the activation energy. The analysis of the beta-relaxation of the copolymers showed that it consists of two components, the first of which is due to the MMA units relaxation, and the second due to the relaxation of styrene units. The results on the alpha-relaxation of the copolymers exhibit only one relaxation process, whose characteristics lie between those of PMMA and PS. The alpha-relaxation of PMMA spreads out to low temperatures. Alpha relaxation process of each of the polymers and the physical ageing effects on this relaxation have been analysed on the basis of the quasi point defect theory developed in the laboratory. The theory accounts for all the experimental results and further provides a physical interpretation of the observed phenomena in these polymers. Such a study provides evidence for the relation between the mechanical behaviour and molecular architecture of polymers

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Hayirlioglu, Arzu. "Directed Assembly of Block Copolymer Films Via Surface Energy Tunable Elastomers". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399049231.

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Saraiva, Greice Kelle Viegas. "Caracterização de copolímeros e efeito da estrutura em sistemas biomiméticos". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-23092015-143832/.

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Copolímeros, macromoléculas orgânicas ou inorgânicas com alta massa molar, consistem de unidades monômericas repetidas, unidas por ligações covalentes e que apresentam mais de um tipo de monômero. Neste trabalho estudamos três copolímeros constituídos por dois blocos distintos, isto é copolímeros dibloco, onde um dos blocos é constituído pelo polimetacrilato de metila, PMMA e o outro pelo polimetacrilato de N,N dimetilamino, PDMAEMA, e o homopolímero de PDMAEMA. A fórmula geral dos copolímeros dibloco estudados é PMMAm-b-PDMAEMAn onde o número de monômeros de cada bloco é representado pelos índices m e n. Os copolímeros PMMA1-b-PDMAEMA6,3 (MM, 54.200), PMMA1-b-PDMAEMA3,0 (MM 27.558), o PMMA1-b-PDMAEMA1,1 (MM 25.555) e o homopolímero PDMAEMA (MM 41.614,9) tiveram suas massas molares e a razão entre os monômeros de cada bloco caracterizados por cromatografia de gel permeação, GPC, e NMR. Determinamos a concentração micelar crítica (CMC) dos copolímeros e verificamos, por RMN e fluorescência, o efeito da concentração e do pH na sua agregação. A interação dos copolímeros com vesículas unilamelares grandes, LUVs, preparadas com misturas de fosfatidilcolina, PC, e fosfatidilglicerol, PG, foi estudada em diferentes condições de pH e força iônica. A interação dos polímeros com as LUVs também foi estudada medindo-se o diâmetro hidrodinâmico e potencial zeta das LUVs na presença dos polímeros. Observou-se que, quando a razão polímero/lipídio é alta, os polímeros se ligam às LUVs, neutralizando completamente a carga das vesículas. Quando a concentração de LUVs é próxima à dos polímeros, forma-se uma rede que conduz à agregação e precipitação dos complexos. Estudamos o efeito dos polímeros na permeabilização de LUVs e vesículas unilamelares gigantes (GUVs) preparadas com misturas de PC:PG. Os copolímeros permeabilizaram as LUVs, dependendo da razão polímero/lipídio, do pH, força iônica e das características hidrofóbicas e hidrofílicas de cada copolímero. Quanto maior a porcentagem de PG nas LUVs maior a interação com os copolímeros. A ligação dos copolímeros às LUVs deve produzir segregação dos fosfolipídios negativos na bicamada das LUVs (i.e., separação lateral de fases) facilitando a permeabilização das vesículas. Demonstramos que os copolímeros se ligam à superfície das GUVs modificando a sua forma e levando ao rompimento das vesículas. Estes efeitos foram modulados pelo pH e a força iônica do meio. O efeito de permeabilização dos copolímeros foi correlacionado com as razões entre os blocos hidrofóbicos e hidrofílicos. Quando o copolímero tem uma maior fração de PDMAEMA, o bloco mais hidrofílico do copolímero, este efeito é mais evidente. A porcentagem de permeabilização, após um tempo definido, para copolímeros de mesma massa molar, como o PMMA1-b-PDMAEMA3,0 (MM 27.558) e o PMMA1-b-PDMAEMA1,1 (MM 25.555), é muito maior com o copolímero com maior porção hidrofílica, o PMMA1-b-PDMAEMA3,0. O homopolímero DMAEMA também se mostrou eficiente na interação com as LUVs, porém menos que o PMMA1-b-PDMAEMA6,3.que possui maior numero de unidades DMAEMA e uma sequencia de monômeros de MMA. Demonstramos, nesta Tese, que o efeito de copolímeros sintéticos contendo regiões hidrofóbicas e hidrofílicas são bons modelos de peptídeos e proteínas permitindo avaliar quantitativamente o efeito dessas interações em modelos de membranas.
Copolymers are organic or inorganic macromolecules with high molecular weight, consisting of repeated monomer units joined by covalent bonds and exhibit more than one type of monomer. Here, we studied three copolymers consisting of two different blocks, i.e. diblock copolymers, where one block is constituted by methyl polymethacrylate, PMMA and other by polymethacrylate N, N-dimethylamino, PDMAEMA and a homopolymer PDMAEMA. The general formula of the diblock copolymers studied was PMMAm-b-PDMAEMAn where the number of monomers of each block is represented by indexes m and n. The PMMA1-b-PDMAEMA6,3 copolymers (MW, 54,200), PMMA1 PDMAEMA3,0-b (MW 27,558), the PMMA1 PDMAEMA1,1-b (MW 25,555) and PDMAEMA homopolymer (MW 41614.9) had their molecular weights and the ratio between the monomers of each block characterized by gel permeation chromatography, GPC, and NMR. The critical micelle concentration (CMC) of the copolymers was determined by fluorescence and the aggregation of the copolymers verified by NMR. The effect pH on the copolymers CMC was also determined. The interaction of copolymers with large unilamellar vesicles, LUV, prepared with mixtures of phosphatidylcholine, PC, and phosphatidylglycerol, PG, was studied under different conditions of pH and ionic strength. The interaction of the polymers with the LUVs was also studied measuring the hydrodynamic diameter and zeta potential of the LUVs in the presence of the polymers. It was observed that when the ratios polymer / lipid are high, the polymers bind to the LUVs, completely neutralizing the charge of the vesicles. When the concentration of LUVs is close to that of the polymers, it forms a network that leads to aggregation and precipitation of the complexes. We studied the effect of polymers in permeabilization LUVs and giant unilamellar vesicles (GUVs) prepared with PC:PG. The copolymers permeabilized the LUVs, depending on the ratio polymer / lipid, pH, ionic strength and the hydrophobic and hydrophilic characteristics of each copolymer. The higher the percentage PG LUVs lead to greater interaction with the copolymers. The binding of the copolymers to the LUVs with negative charge induced phase separation of phospholipids in the bilayer of LUVs (ie, lateral phase separation) facilitating the permeability of the vesicles. We demonstrate that copolymers bind to the surface of GUVs changing its shape and leading to rupture of vesicles. These effects are modulated by pH and ionic strength of the media. The permeabilization effect of the copolymers was correlated with the ratios of the hydrophobic and hydrophilic blocks. When the copolymer has a larger fraction of PDMAEMA, the more hydrophilic block copolymer, this effect is more evident. The percentage of permeabilization, after a set time, for the same molar mass copolymers such as b-PDMAEMA3,0 PMMA1 (MW 27,558) and PMMA1 PDMAEMA1,1-b (MW 25,555), is much more efficient with copolymer with greater hydrophilic portion, the b-PMMA1 PDMAEMA3,0. The DMAEMA homopolymer also proved efficient in interacting with the LUVs. We demonstrated that synthetic copolymers containing hydrophobic and hydrophilic regions are good models of peptides and proteins allowing quantitatively evaluate the effects of these interactions on model membranes

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Adapa, Deekshitha. "Sorption of Benzene, Tolueneand Ethylbenzeneby Plasticized PEMA and PEMA/PMMA Sensing Films Using aQuartz Crystal Microbalance (QCM) at 298.15K". Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7720.

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Detection of volatile organic compounds (VOC’s) in the environment is important for human health and wellness. Long term exposure of certain VOC’s like benzene, toluene, ethylbenzene and xylene (BTEX) has a severe effect on human health. There are techniques such as gas chromatography, photo ionization, and mass spectroscopy that are time consuming, require gas sampling and are ineffective in real time sensing in air. Acoustic wave devices such as surface acoustic wave (SAW) devices can be used for sensing BTEX compounds in both vapor and liquid phase. The quartz crystal microbalance (QCM) is a low-frequency acoustic wave device, which can be used to characterize polymer film sensing quickly and easily by studying the sorption properties of BTEX compounds in them. In this work, thin films (~ 0.5 microns) of polymer/plasticizer blends are spin-coated on a 5MHz QCM for the detection of VOC’s. A polymer/plasticizer combination of poly (ethyl methacrylate) (PEMA) and a copolymer of poly (ethyl methacrylate) and poly (methyl methacrylate) (PEMA/PMMA) with di n-butyl phthalate (DBP), di-n-butyl sebacate (DBS) and n-butyl stearate (BS) are used for the detection of benzene, toluene and ethylbenzene in vapor phase. The working apparatus consists of a stream of solvent vapor diluted with nitrogen to an arbitrary concentration passing over the QCM oscillated to its resonant frequency. The sorption data are reported at 298.15 K in terms of activity as a function of weight fraction curves and are interpreted with the Flory-Huggins ternary model. The addition of plasticizer modifies the free volume properties of the polymer, thereby increasing diffusion and sensitivity of BTEX vapors. The plasticizer composition is tailored to 17.5%, for maximum sorption with minimal viscoelastic effects. The sorption and sensitivity of BTEX are interpreted and studied in terms of plasticizer type and concentration.

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12

Freluche, Mathilde. "Copolymères greffés et matériaux nanostructurés à base de polyméthacrylate de méthyle et de polyamide-6". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2005. http://tel.archives-ouvertes.fr/tel-00079021.

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Cette étude porte sur l'élaboration de matériaux polymères nanostructurés à base de poly(méthacrylate de méthyle) (PMMA) et de polyamide-6 (PA-6). Les mélanges sont réalisés par extrusion réactive, c'est à dire par mélangeage en fondu de chaînes de polymères portant des groupes mutuellement réactifs. La réaction de greffage a lieu entre la fonction amine en bout de chaîne du PA-6 et des groupes anhydride le long des chaînes de PMMA. Les compositions des mélanges extrudés et des copolymères formés peuvent être déterminées, dans la plupart des systèmes, à l'aide d'une méthode de caractérisation principalement basée sur la chromatographie d'exclusion stérique. Ces résultats combinés à la microscopie électronique en transmission ont permis de déterminer les caractéristiques optimales des polymères employés (composition du PMMA réactif et taille des chaînes de PA-6) afin de former des mélanges nanostructurés. Dans ce système, la formation de mélanges nanostructurés est limitée à des PA-6 de faible masse molaire. En revanche, lorsqu'un copolymère à bloc contenant deux blocs PMMA fonctionnalisés anhydride et un bloc central incompatible est utilisé dans les mélanges, la taille de la dispersion n'est que légèrement affectée par la taille des chaînes de PA-6. La cristallinité du PA dans les matériaux nanostructurés a été étudiée. Les propriétés des matériaux étudiées ici (résistance aux solvants et évolution du module de conservation avec la température) peuvent être corrélées à leur structuration et à la connectivité des domaines de PA-6 dans le matériau.

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13

Courbaron, Anne-Claude. "Gestion de la dispersion des MWNT par adsorption et greffage de copolymères PAA-PMMA pour le renforcement d’un polyépoxyde". Pau, 2010. http://www.theses.fr/2010PAUU3007.

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L’interface entre les nanotubes de carbone multi parois (MWNT) et la résine époxyde est en grande partie responsable de l’état de dispersion et de la transmission des contraintes mécaniques. Pour améliorer l’adhésion interfaciale, nous proposons de greffer des copolymères à blocs à la surface des MWNT via une polymérisation «in situ». Les copolymères de l’étude sont composés d’un bloc de polyacide acrylique (PAA) et d’un bloc de polyméthacrylate de méthyle (PMMA). L’étude des cinétiques de polymérisation des copolymères et de réticulation de l’époxyde a permis de montrer l’effet catalyseur des MWNT. Le greffage est mis en évidence par l’étude des températures de dégradation des copolymères. Nous avons montré que les copolymères choisis favorisent la dispersion des nanotubes. Les MWNT greffés PAA-PMMA présentent une efficacité supérieure aux MWNT adsorbés PAA-PMMA et permettent d’obtenir des dispersions de bonne qualité. Les effets du taux de copolymères, de leurs masses molaires moyennes et des densités de greffage ont également été analysés du point de vue des dispersions. Nous avons caractérisé les propriétés mécaniques des nanocomposites (polyépoxyde + nanocharges) en fonction de l’état des dispersions et des interactions copolymères – MWNT. Lorsque l’interface est rendue compatible grâce aux copolymères adsorbés ou greffés, les propriétés rhéologiques du polyépoxyde sont nettement améliorées, particulièrement dans le cas des MWNT greffés PAA-PMMA pour lesquels la dispersion est la meilleure
Interface between multi wall carbon nanotubes (MWNT) and epoxy matrix is admitted to play an important role in the dispersion quality and mechanical stress transfer. To improve the interfacial adhesion, we propose to chemically graft block copolymers onto MWNT surface using an “in situ” polymerisation. Herein, block copolymers are composed of one polyacrylic acid block (PAA) and one polymethyl methacrylate block (PMMA). The studies of polymerization kinetics, and cure epoxy showed the catalytic effect of MWNT. The grafting is highlighted by the study of copolymers degradation temperatures. Block copolymers make easier the MWNT dispersion in epoxy resin. MWNT grafted PAA-PMMA are more efficient than MWNT adsorbed PAA-PMMA, and give well dispersed nanotubes. The influence of copolymers proportion, molecular weight and grafting densities are also analyzed for the dispersion aspect. We characterized the mechanical properties of epoxy composites according to the dispersion quality and copolymers – MWNT interactions. It appears that when the interface is made compatible thanks to adsorbed or grafted copolymers, the rheological epoxy properties are clearly improved, especially with MWNT grafted PAA-PMMA which offer the best dispersion

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14

Ferrari, Federico. "Synthesis of Metal-Binding Ligand-Containing Copolymers, Nanoparticles and Blends". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19186/.

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In this thesis we developed three copper-containing systems. Copper shows intriguing abilities in photocatalysis, however, one of the major limitations of many copper complexes is that photochemical properties might be quenched in solution caused by π-interactions between solvent and solute, due to Jahn-Teller distortion in the excited state. As such, we herein seek to synthesise copper heteroleptic complexes that will subsequently be nanoprecipitated with a polymer. This will allow the polymer to encase the complex and prevent the solvent-induced quenching. Subsequently, the preparation of blends of polymer with the aforementioned copper complexes, at different weight ratios is sought. The preparation of the blend is particularly interesting as the catalytic properties are anticipated to be inferior on account of the low surface area. However, owing to the polymer matrix better, mechanical properties are anticipated. The blends can combine the mechanical properties of the polymer and the luminescence of the complex, with the advantage that the polymer matrix can also prevent quenching from oxygen. As final task, we developed a copper-containing monomer. The synthesis of a monomer that contains copper and can be excited under ultraviolet (UV) light is particularly interesting.

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15

Hutjens, Charles Michael. "Morphology Control for Model Block Copolymer/Nanoparticle Thin Film Nano-Electronic Devices on Conductive Substrates". University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1374496041.

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16

Meyer, Jens [Verfasser] y Mathias [Akademischer Betreuer] Ulbricht. "PVDF Ultrafiltrationsmembranen mit maßgeschneiderter Trennleistung durch Einsatz von PEO-b-PMMA Diblock Copolymeren / Jens Meyer ; Betreuer: Mathias Ulbricht". Duisburg, 2018. http://d-nb.info/1159879338/34.

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17

SABY, DUBREUIL ANNE-CLAIRE. "Sechage de films polymeres : etude du couplage entre la diffusion et la transition vitreuse - application a des copolymeres pmma/pnbma". Paris 6, 2001. http://www.theses.fr/2001PA066369.

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Les cinetiques de sechage de solutions polymeres dependent principalement, dans le regime concentre, de la diffusion du solvant dans la solution et de son couplage avec la transition vitreuse. Dans ce cadre, nous nous sommes interesses aux comportements de sorption/desorption d'une serie de copolymeres pmma/pnbma, a temperature constante (t = 25\c) et en regime concentre en polymere, et nous avons etudie l'influence de la transition vitreuse induite par la variation de la concentration de la solution polymere en fonction de la composition du copolymere. Une technique gravimetrique mettant en uvre une microbalance a quartz piezoelectrique est utilisee. Les echantillons sont des films minces, d'epaisseur inferieure a un micrometre. Des experiences de quasi-equilibre ont montre que la quantite de solvant absorbee dans le film en regime vitreux varie de facon importante selon l'etat de la structure de la matrice polymere. Pour les isothermes de desorption en regime vitreux, celui-ci peut etre caracterise a l'aide du module elastique osmotique intervenant dans le modele de leibler-sekimoto. Les resultats obtenus montrent un ecart significatif par rapport aux modules des polymeres secs. Les cinetiques pseudo-fickiennes observees en reponse a des echelons de pression differentiels traduisent un couplage entre la diffusion et la relaxation viscoelastique de la matrice polymere. Coefficient de diffusion mutuelle et temps caracteristique de relaxation sont evalues a l'aide du modele de solubilite dependant du temps. Une methode d'identification globale, l'inversion ensembliste, est adoptee : elle permet de tenir compte des erreurs de mesure et donne acces au domaine d'incertitude attache a chaque parametre du modele. Nous avons montre que le coefficient de diffusion mutuelle decroit tres fortement a la fois quand la proportion en monomeres nbma diminue et quand la concentration en solvant diminue, bien que les resultats soient obtenus en regime vitreux.

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18

Maire, Helene C. "Characterization of cylindrical nano-domains in thin films of polystyrene-poly(methyl methacrylate) diblock copolymer studied via atomic force microscopy". Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1037.

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19

Freluche, Mathilde. "Copolymères greffés et matériaux nanostructurés à base de poly(méthacrylate de méthyle) et de polyamide-6". Paris 6, 2005. https://tel.archives-ouvertes.fr/tel-00079021.

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20

Dronet, Séverin. "Matériaux nanostructurés obtenus par combinaison de polymérisation radicalaire contrôlée et de mélangeage réactif". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00430883.

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Dans cette étude, nous avons réalisé des matériaux nanostructurés à partir de copolymères méthacryliques greffés par du polyamide 6. Le greffage s'effectue par mélangeage réactif en faisant réagir la terminaison amine du polyamide sur des fonctions réactives du squelette méthacrylique. En étudiant différentes architectures de squelette, nous avons remarqué que la distribution des sites réactifs jouait un rôle important. Dans le but de comprendre cet effet sur la structuration et les propriétés mécaniques de ces matériaux, nous avons synthétisé des copolymères modèles de méthacrylate de butyle par polymérisation radicalaire contrôlée (méthode ATRP). Pour bien contrôler l'architecture de ces copolymères, nous avons développé un système de suivi de la polymérisation, par spectroscopie en proche infrarouge, nous permettant de connaître en temps réel la longueur des chaînes formées. Nous avons ainsi obtenu une variété de copolymères bien contrôlés (masses molaires voisines, polymolécularités faibles) dont les sites réactifs (acide méthacrylique) sont répartis statistiquement sur toute la chaîne (architecture monobloc), sur une partie de la chaîne (dibloc) ou sur les deux extrémités de la chaîne (tribloc). Le greffage du polyamide sur ces squelettes a ensuite été réalisé à l'état fondu en extrudeuse, et nous avons étudié la structuration par microscopie électronique (TEM), les propriétés mécaniques par analyse dynamique (DMA), la cristallisation par analyse enthalpique différentielle (DSC) ainsi que la résistance aux solvants de ces matériaux. Tout d'abord, l'efficacité de greffage du polyamide sur les squelettes méthacryliques est très élevée (jusqu'à 90%) et augmente avec la densité de sites réactifs. Ensuite, la distribution des sites réactifs, donc des greffons polyamide, influence fortement la structuration des mélanges et leurs propriétés. Nous avons pu définir le type de squelette à utiliser pour obtenir une morphologie donnée. Finalement, les résultats de cette étude ont été utilisés pour réaliser des matériaux nanostructurés à partir de squelettes triblocs élastomériques PMMA-b-PABu-b-PMMA et PS-b-PABu-b-PS. Nous avons ainsi obtenu des élastomères thermoplastiques hautes performances transparents, résistants aux solvants et avec une tenue mécanique dépassant les 200°C.

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21

Sully, Yves. "Synthèse de latex acryliques et styréniques en présence de copolymères a blocs PMMA-B-POE : Application a la protection de substrats metalliques". Mulhouse, 1998. http://www.theses.fr/1998MULH0539.

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En vue de réaliser des latex terpolymères statistiques destines a servir de protection temporaire pour des substrats métalliques, nous avons étudié la polymérisation radicalaire en émulsion de monomères acryliques et styreniques, cela en présence de tensioactif non-ionique macromoleculaire de type copolymères à blocs PMMA-b-POE poly(methacrylate de methyle) -bloc- poly(oxyde d'éthylène). L'objectif recherche consistait en l'obtention de donnes permettant de caractériser l'influence de ce type d'agent d'émulsification sur la (co)polymérisation de monomères (meth)acryliques et styreniques, ceci afin de cerner les comportements cinétiques et les caractéristiques colloïdales mis en jeu. A ce propos, nous avons montre que les valeurs des coefficients reliant le nombre de particules (np) à la concentration en tensioactif étaient typique des tensioactifs macromoléculaire, à savoir une valeur bien supérieure a celle de 0. 6 usuellement rencontrée pour les émulsifiants classiques de type sds. En ce qui concerne le modèle de nucléation, il semblerait que le modèle de nucléation propose par smith et ewart, notamment dans le cas des homopolymères ps, soit a même d'expliquer les phénomènes rencontres et en particulier pour ce qui est du nombre moyen de radicaux (n). Quant a l'étude des propriétés thermiques (t#g) des films de latex contenant un tel tensioactif, nous avons mis en évidence l'existence d'un processus de plastification des films de latex par ce type de tensioactif.

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22

Badel, Thierry. "Synthèse de copolymères par greffage radicalaire de méthacrylate de méthyle sur polyoléfine par extrusion réactive, en vue de la nanostructuration". Phd thesis, Université Claude Bernard - Lyon I, 2005. http://tel.archives-ouvertes.fr/tel-00149291.

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Ce travail porte sur le greffage radicalaire de méthacrylate de méthyle sur un poly(éthylène-co-1-octène) par extrusion réactive. Le contrôle de l'architecture des copolymères greffés nécessite la compréhension des mécanismes réactionnels mis en jeu, à température et viscosité élevées. Grâce à une étude sur molécules modèles, les sites de greffage, les réactions gouvernant la masse molaire des greffons, ainsi que les réactions compétitives à l'origine de l'homopolymérisation ont pu être quantifiées. L'étude modèle, complétée par une simulation numérique, souligne la nécessité de diminuer la température du milieu réactionnel pour favoriser la réaction de greffage. Parallèlement, l'extrusion réactive confirme les tendances dégagées par l'étude modèle et met en évidence l'influence des conditions de mélange sur la morphologie. Enfin, l'utilisation de radicaux nitroxyles pour limiter la réaction d'homopolymérisation, n'améliore pas significativement l'efficacité du greffage.

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23

He, Guping [Verfasser], Brigitte [Akademischer Betreuer] Voit y Christine [Akademischer Betreuer] Papadakis. "The Effect of Modified AuNPs on the Morphology and Nanostructure Orientation of PPMA-b-PMMA Block Copolymer Thin Films / Guping He. Gutachter: Brigitte Voit ; Christine Papadakis. Betreuer: Brigitte Voit". Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://d-nb.info/1068448865/34.

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24

Pyreňová, Eliška. "Studium vlastností polymery modifikovaných malt využívající pucolánově aktivní materiály". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240307.

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This diploma thesis is focused on the study of the properties of polymer-modified cementitious mortars which using pozzolanic active materials based on amorphous silica. Explores the possibilities of using the recycled glass as a partial replacement of cement in PMM. Properties of mortars are reviewed in mineralogical and technological point of view. For specification of the results were used the analysis RTG, DTA and REM.

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25

Datta, Uttam. "Synthesis and Self-Assembly of Organometallic Semiconducting PMMA-b-PFS-b-PS-b-PFS-b-PMMA Pentablock Copolymers". Phd thesis, 2005. http://tuprints.ulb.tu-darmstadt.de/588/1/Uttam_Datta.pdf.

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It was the goal of the present work to synthesize a series of well-defined pentablock copolymers of styrene (S), [1]dimethylsilaferrocenophane (FS) and methyl methacrylate (MMA) by sequential addition of monomers. Lithium naphthalide was used as difunctional initiator and a 1,1-dimethylsilacyclobutane (DMSB) mediated 1,1-diphenylethylene (DPE) end-capping technique was applied to ensure high block efficiency. The PMMA-b-PFS-b-PS-b- PFS-b-PMMA systems have molecular weights of Mn = 50,000 g/mol, polydispersity indices of PDI ≤ 1.12 and PFS volume fractions of around φ PFS=0.15. First, the difunctional middle block of PS was formed, followed by triblock PFS-b-PS-b-PFS, which then - after appropriate end-capping - was employed as a macroinitiator to polymerize MMA, leading to the final pentablock copolymer. The block copolymers were characterized by SEC and NMR. Under optimum reaction conditions - i.e. when chain termination during DPE/DMSB end-capping is minimized - the pentablock copolymer was obtained in approximately 75 % purity: the crude product contained - in addition to the pentablock - some tetrablock (20%) and triblock (5%) copolymers. This raw material, however, could be purified by selective precipitation procedures which addressed the differences in polarity of the constituents. By that method, almost quantitative removal of the triblock was possible whereas a small amount of the tetrablock remained in the pentablock fraction. Fortunately the presence of such small amounts of tetrablock copolymers did not influence the pentablock copolymer micromorphologies in an irreproducible way. Thus, profound investigations were possible to analyze the bulk properties of the materials. The pentablock copolymers were examined with the help of TEM and SAXS for their microphase behavior. The self-assembly was studied starting from dichloromethane, tetrahydrofuran and toluene solutions, after taking into consideration the solubility parameters. The formation of thermodynamically stable micromorphologies was forced by storing the solvent cast films in the saturated atmosphere of the corresponding solvent for 3-4 weeks followed by annealing at elevated temperatures 180 DegC - 220 DegC. Prior to this, it was ensured by TGA and DSC analysis that the pentablock copolymers are of sufficient thermal stability for this treatment. Annealing under various conditions followed by TEM analysis revealed good phase separation and the formation of highly ordered microstructures, such as spheres-on/in-spheres, spheres on lamellar interface, biphasic lamellar, cylinders and spheres on cylinders micromorphologies. These morphologies were further verified and supported by SAXS scattering profiles. Conductivity measurements on original and doped samples (I2 and TCNE) of PFS containing homo and block copolymers with/without microphase separation were carried out by dielectric spectroscopy (DRS). The maximum conductivity observed for the doped PFS sample (10-7 S/cm) decreased to 10-10 S/cm on dilution by domains of PS and PMMA in the block copolymers of various architectures.

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26

Chao, Yu-Sheng y 趙禹昇. "Structures and properties of PS/PMMA copolymers prepared using organogels as nano-templates". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/67392650277678344923.

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碩士
淡江大學
化學工程與材料工程學系碩士班
98
This research focus on preparation of nanostructured polymeric materials by polymerization at monomers within a scaffold composed of self-assembled 1,3:2,4-Dibenzylidene sorbitol (DBS) nanofibrils. We induce DBS nanofibrils in St-MMA monomers and then thermally initiate the free-radical polymerization of the monomers. The plate rheometer results show that the samples are organogels and elastic modulus will higher at the higher DBS concentration. The TEM results show that the DBS nanofibrils form the different morphology under the different monomers environment. When St monomer more then MMA monomer the nanofibrils will be scattered. When MMA monomer more then St monomer the nanofibrils will be gather. By GPC analysis, we found that adding DBS in polymeric can slightly decrease the molecular weights. The TGA and DSC analysis show that adding DBS in polymeric the decomposition temperature did not variation but the glass transition temperature will slightly decrease. The SEM results show that we can find the sign of DBS nanofibrils wash by alcohol at PS sample but we can not find the sign of DBS nanofibrils wash by alcohol at PS-PMMA and PMMA sample.

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27

Yeh, Je-Yuan y 葉哲源. "Preparation and micellization of block copolymers (PS-b-PMMA) of various chain lengths". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/60953132945619439186.

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碩士
逢甲大學
化學工程學所
95
Polystyrene-b-polymethyl mathacrylate (PS-b-PMMA) copolymers with various block chain lengths were prepared via stable free-radical polymerization (SFRP). Acetone and toluene were used as the solvent, respectivety, to study the micellization. The micellar types and sizes depend on the relative chain lengths of two blocks. The critical micellar concentraction (CMC) was determined by using the Du Nouy’s tensionmeter, the micellar size was decided by using the dynamic light scttering (DLS), and the size and shape of micelle was also determined by using scanning electron microscope (SEM). Although the molecular weight increases with conversion , we found that the polymerization is not exclusively ”living”.The hydrodynamic radius of eatch block copolymer was determined by using DLS at concentraction below CMC. It was found that the aggregation may have size deviate from the normal dimension for either the micellar size or the single molecular size. The calculation found that the micelle was constituted of fewer molecules when the polymer has the larger solvo- philic chain length.

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28

Datta, Uttam [Verfasser]. "Synthesis and self-assembly of organometallic semiconducting PMMA-b-PFS-b-PS-b-PFS-b-PMMA pentablock copolymers / eingereicht von Uttam Datta". 2005. http://d-nb.info/97586307X/34.

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29

Wang, Teng-yi y 王騰逸. "Control of Film Morphologies in Self-Assembly of High-Mw PS-PMMA Block Copolymers". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26132187897235058051.

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碩士
國立中山大學
材料與光電科學學系研究所
101
Control of film morphologies to generate one-dimensional (1D) or three-dimensional (3D) polymeric photonic crystals from self-assembly of high-Mw polystyrene-b-polymethylmethacrylate (PS-PMMA) block copolymers (BCPs) is conducted in this study. Microphase-separated lamellar and gyroid phases can be observed in the bulk samples of high-Mw PS-PMMA BCP by transmission electron microscopy (TEM). Disordered morphologies are observed in the as-spun PS-PMMA thin films from poor solvents for PMMA (i.e. benzene, toluene, and divinylbenzene) due to fast evaporation of solvents. After solvent annealing by benzene, PMMA micelles in a PS matrix can be obtained. By contrast, coexistence of parallel and perpendicular lamellar microstructures is found in the PS-PMMA thin film after solvent annealing by neutral dichloromethane. In contrast to as-spun disordered morphologies from PMMA poor solvents, microphase-separated bicontinuous or lamellar microstructures are observed in the as-spun PS-PMMA thin films from PS-selective 1,1,2-trichloroethane or chloroform. After solvent annealing by neutral dichloromethane or 1,2-dichloroethane, the improvement of the lateral arrangement for the gyroid phase can be found. Also, a phase transition from the as-spun bicontinuous to lamellar microstructures are obtained using PS-selective solvents such as chloroform and 1,1,2-trichloroethane for annealing. Except for solvent-induced microstructural orientation, large-area and well-oriented lamellar microstructures parallel to the substrate can be successfully carried out in the PS-PMMA thick film by shear-induced orientation. Accordingly, 1D BCP photonic crystals are fabricated from the self-assembly of the lamella-forming PS-PMMA. The red- and blue-shifting reflectivity bands of the 1D BCP photonic crystals can be stimulated by the swelling and de-swelling of the microdomain driven by solvent vapor, revealing the reversible solvatochromic behavior. Also, the complexation of PMMA with metal salts is performed in the high-Mw PS-PMMA BCP. After complexation, the increase of segregation strength of microphase segregation and the decrease of the refractive index contrast may give rise to the formation of strong-segregated lamellar microstructures with sharp reflectivity bandwidth in the metal-complexed PS-PMMA. As a result, the solvent-responsive 1D BCP photonic reflectors with tunable bandwidth can be successfully carried out in the PS-PMMA BCP films having well-aligned microstructural orientation by solvent- and shear-induced orientation.

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30

HUANG, PO-HAN y 黃柏翰. "Synthesis and Properties of Nanocomposites , Copolymers and Particle Toughened PMMA Based on Novel Acrylates". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/n4687j.

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碩士
義守大學
生物技術與化學工程研究所
102
This research includes three major parts. The first part of the research is to copolymerize methyl methacrylate with three different monomers, which are dipropylene glycol mono-methyl ether acrylate(DOBA), propylene glycol mono-methyl ether acrylate(OBA1) and its isomers, OBA2, through the method of solution polymerization with different proportions, aollowing by the investigation of the thermal stability and the optical properties of the copolymers. The results turn out that compared with PMMA, the copolymers have an enhancement in thermal stability and better potentiality in toughness enhancement. The second part of the research is to prepare nanocomposites, POBA1/clay, POBA2/clay and PDOBA/clay. We added different proportions of modified clay into monomers of OBA1, OBA2 and DOBA. Then, we synthesized nanocomposites, POBA1/clay, POBA2/clay and PDOBA/clay by miniemulsion polymerization, and conduct investigation of their structure, thermal stability. The results show that the nanocomposites we made are intercalated nanocomposites with partially-exfoliated structure, which have a great improvement in their thermal stability. All in all, PMMA has the best optical property of all plastics. It not only excels in weatherability, but also has a wide range of application. However, PMMA is brittle, which makes its impact resistance unideal. Therefore, the third part of the research is to produce particle toughened PMMA to improve its impact resistance. In the experiments, we prepare particles of POBA1, POBA2 and PDOBA by emulsifier-free emulsion polymerization. Then, by the method of mass polymerization, we scatter different proportion of those particles onto the monomers of MMA to create particle toughened PMMA and test the thermal stability, mechanical properties and other characteristics of the particle toughened PMMA. The result shows that the particle toughened PMMA we create have an enhancement in toughness and further increase its thermal stability.

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31

Finkhäuser, Stefanie. "Mechanische Spektroskopie an PMMA-Systemen: Nichtlineares Verhalten und UV-aktive Blockcopolymere". Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0023-3DDB-B.

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32

chien, Hao-Ching y 簡豪慶. "Effect of Phase Separation Morphology on the Adhesion of PS/PMMA Interface Reinforced with Mixed Composition of Random Copolymers". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/12803311927686075765.

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碩士
國立臺灣大學
化學工程學研究所
92
We have measured the fracture toughness of interface between polystyrene (PS)/poly methyl methacrylate (PMMA) using mixed composition of different random copolymers of PSf-r-PMMA1-f, where f is the volume fraction of PS in the random copolymer. Nine different composition of PS-PMMA were used with f ranging from 0.1 to 0.9. We have found the fracture toughness of interface can be significantly increased with mixed random copolymer compared with that from the copolymer of single composition. It is found that with increasing concentration of the mixed random copolymer at the interface, the Gc of the interface increase quickly and finally reaches a plateau around 140 j/m2. SIMS experiments confirmed that the mixed composition of differ- ent random copolymers organize at the interface to form an artificial composition drift .It also shows the fracture toughness of a interface with multicomponents is strongly affected by annealing time. We interpret this time-effect on Gc is related with the formation of the two dimension phase separation of the blending thin film followed by TEM and AFM technic. We suggest that fracture toughness increases with time in the beginning of annealing under the interfacial welding mechanism and the rearrangement of random copolymers at PS/PMMA interface, and decreases later with the dilute mechanism which minimizes the domain size of PS-rich island. Because such phase separation structure is submicrometer-scale, minimizing of the domain size would result in the worse stability of the initiation and the widening of PS-crazing fibril. The failure mechanism is examined by ATR-FTIR technique. This method suggests a simple method for one to effectively use random copolymers for reinforcement.

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33

Huang, Yu-ming y 黃昱明. "Synthesis of PE-b-PMMA Block Copolymer with Nanoporosity". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/16921443029927955338.

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碩士
國立中正大學
化學工程所
96
A Thin polyethylene (PE) film containing nanoporosity has been formed. First, we cast a PE-b-PMMA block copolymer into a thin film for the PMMA to self-assemble as cylinders. Then, with the removal of the PMMA phase we obtain a thin PE film with nanoporosity. Poly(ethylene-block- methylmethacrylate) is formed via hydrogenation of poly(butadiene-block-methylmethacrylate) which has been synthesized using anion polymerization. To achieve the desired morphology, we have blended homo- polymethylmethacrylate into PE-b-PMMA metioned before. The nano-porosity is formed by removing the PMMA phase via UV- Light degradation. GPC、NMR、TGA、DSC、UV-Vis Spectrometer、FTIR、AFM、SEM have been used in our work extensively in order to ascertain the molecular structure and determine the physical properties.

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34

Yi-Chun, Lee y 李奕均. "Synthesis and Photochromic Behaviors of Azobenzene-based PMMA Copolymer". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/23266077060293225295.

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碩士
輔仁大學
化學系
89
Optical data storage materials are mainly based on organic molecules. To be suited used as an optical data storage material, molecules has to be photochromic ; i.e., they must be capable of being reversibly switched between two spectroscopically distinct forms by use of light. The photochrome that we have chosen is a substituted azobenzene, which shows a cis-trans isomerization on either a photochemical process or a thermal process. The geometric configuration of the azo bond in azobenzene based compounds can be reversibly switched from trans to cis. The two states have distinct absorption spectra. However, this cis state is thermodynamically unstable with respect to the trans state; therefore a thermal relaxation process occurs even in the dark( at room temperature ). The thermal back-reaction strongly limits the lifetime of the cis state and it should be influenced by the substituent on the azobenzene moiety, temperature and the environment( i.e., solvent type, solvent polarity, type of polymer matrix etc. ). In this study, azobenzene-based PMMA was synthesize by copolymerization of MMA with azobenzene moiety-tagged MA( methacrylate ). The azobenzene moiety was attached with different electron-withdrawing group( i.e., NO2, CN ),and different spacer length was built between the polymer chain and the azobenzene chromophore. Our results showed that slow back-isomerization( cis to trans )rate was observed in the solution sample when proceeded with weaker electron-withdrawing group, shorter spacer length and lower content of azobenzene-tagged MA. Whereas no significant difference was found when a film sample was used.

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35

H, Chen C. y 陳俊宏. "Synthesis and Dielectric Behaviors of Azobenzene-based PMMA Copolymer-Substituent Effect". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/80646617329913690759.

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碩士
輔仁大學
化學系
92
Abstract In this study, azobenzene-based PMMA was synthesized by copolymerization of MMA(methyl methacrylate) with azobenzene moiety-tagged MA(methacrylate). The azobenzene was attached with different electron-withdrawing groups( i.e., -NO2, -CN, -Aceto ),and different spacer length was built between the polymer chain and the azobenzene chromophore. The molar ratio of azobenzene-tagged MA to MMA used were in the range of 1/99 ~ 5/95. A total of 13 copolymers were synthesized in this study. All the copolymer structures were characterized by FT-IR, NMR, GPC, DSC, and TGA. The dielectric analysis showed that the copolymer with shorter space length gave larger dielectric constant than the one with longer space length. All the copolymers gave a scattered results on the dielectric measurements, regardless of the types of electron-withdrawing groups or the amounts of azobenzene moieties. It seems reveal that a poling operation is necessary. On the other hand, a quite steady, constant dielectric property was obtained in the simple mixing blends made of various azobenzene dye with PMMA. It revealed that the types of the electron-withdrawing group and the amount of the dye incorporated( up to ~10% by wt. )played a minor role in affecting the dielectric behavior of these blends.

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36

Kao, Ting-Chung y 高挺鐘. "Process Development for Rapid Self-Assembly of PPV-b-PMMA Block Copolymer". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/91030719978214983258.

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碩士
國立臺灣大學
高分子科學與工程學研究所
104
Rod-coil block copolymers have long been a research interest for their great potentials in nanolithography and flexible optoelectronics applications. By adjusting interactions between segments and their volume fractions, one can acquire various nanoscale morphologies. However, the segment interactions of rod-rod and rod-coil of the copolymers are very strong, the formation of ordered structure is rather difficult even they are annealed under a fairly high temperature for a long time. To promote the formation of ordered structure of rod-coil block copolymer, chemical modifications of side chain or main chain are usually used to suppress interactions, but that affects the original physical properties of pristine copolymers. In this work, we’ve developed a facile method to form a highly ordered nanostructure of PPV-b-PMMA at low temperature and short time without any chemical modification. By adding high boiling point selective additives in the copolymer, the thermodynamic equilibrium of ordered structure can be reached with relatively low temperature and short time. If the high boiling point additive cannot remove during the annealing process completely that will affect the chemical and physical properties of the copolymer. Therefore, we further improve the process by treating the samples under different annealing environment. Two new systems are investigated: open system and vacuum system as compared with the original confined system (sample annealed in a metal washer). The additive has more room to facilitate the movement of copolymer and to be evaporated effectively during the annealing. By optimizing the annealing condition, we can not only retain the nanostructure of the copolymer, but also improve the quality of ordered structure without presence of any additive. For example, vaccum system can help copolymer to form structure in 1.5hr annealing period. This technique provides an efficient and energy-saving process for self-assembly copolymers to form highly ordered structures.

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37

Lai, Mei-Tsu y 賴美足. "Studies of the self-assembly of P3HT-b-PMMA rod-coil diblock copolymer". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/91352740866317339864.

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碩士
國立清華大學
化學工程學系
94
Block copolymer (BCP) self-assembly is an essential part of nanotechnology, and it offers one of the few practical strategies for making ensembles of nanostructures. Self-assembled BCPs have found applications in a number of fields of nanotechnology such as photonic band gap materials, nanostructured networks, nanolithographic templates, etc. Most of the research in this field has been focused on coil-coil BCPs with flexible polymer chains. During the past two decades, rod-coil BCPs, where one of the constituting blocks has a rigid conformation and the other is flexible, have attracted great attention. Due to the combination of two extreme polymer chain conformations (rigid and flexible), complex phase structures and morphologies have been observed. In this study, the self-assembled structure of a conjugated rod-coil P3HT47-b-PMMA220 diblock copolymer was investigated using SAXS, WAXS and TEM. The results showed that this copolymer self-organized to from hierarchical structure with two different length scales. The larger-length-scale structure was formed due to microphase separation between P3HT and PMMA block resulting in P3HT microdomain of ca. 20 nm in diameter embedded in PMMA matrix. The P3HT microdomain further consisted of a smaller-length-scale structure due to the formation of ca. 5 nm in diameter nano-ribbons. The regular layered structure due to the microphase separation between to backbone and side chain of P3HT, in this case, was hindered due to covalent linking with PMMA chains. Furthermore, from temperature-dependent SAXS experiment, an order-disorder transition (ODT) of the nano-ribbon structure in the copolymer was revealed between 50 ~ 80℃.

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38

Kai, Wang Pung y 王鵬凱. "Synthesis and Photochromic Behavior of Azobenzene-based PMMA Copolymer in Solution and Thin Film". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/51933223841794334602.

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碩士
輔仁大學
化學系
90
The photochrome of azobenzene dye will induce trans-cis photoisomerization under ultra-visible light﹒The reverse reaction will be reverse by heat or light with different wavelength；Moreover , there are three properties : 1. Good arrangement of polymer , 2. Good solvation , 3. Good process to be drived easily , which can be applied in storage material of light in this kind of copolymer﹒Therefore , it is quite potential and valuable to do further research﹒ This research is to synthesize monomer with azobenzene and copolymerize with methyl methacrylate (MMA)﹒Then the copolymer will become side-chain copolymer﹒The optical property of this copolymer is worthy of research﹒In this study, the azobenzene moiety was attached with the same electron-withdrawing group and the same spacer length(n=11)﹒Further , we synthesize azobenzene and copolymerize with different mole percentage of MMA to induce copolymerizing reaction﹒The copolymer we get after reaction will be discussed individually in the following two situations:1. Solvent polarity；2. Thin film and studied it`s phenomenon of photochrome﹒I would suggest that each kind of phenomenons in the copolymer are affected by different solvent polarity and their application in the storage material of light in practice﹒The study result shows that photochrome wil isomerizes faster with higher mole percentage of azobenzene in the copolymer﹒However, the rate of isomerization will be faster with higher solvent polarity due to more attractions﹒

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39

Ke, Jiun-Kuang y 柯俊光. "A Study on Direct Writing of PS-b-PMMA Block Copolymer Using Dip-pen Nanolithography". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/77330573540174862379.

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碩士
國立中正大學
光機電整合工程所
95
Block copolymer(BCP) can self assemble into micro phase separation, so BCP is researched popularly. The general fabrication is spin coating, but this method can’t make BCP patterning. We use Dip-pen Nanofabrication to make BCP patterning on the substrate. In the same time, we confer phase separation about the thin film of BCP. The thesis separate into two parts. First we discuss how to transport BCP on the substrate. From experiment result in this thesis, we understand that BCP isn’t transported by water meniscus. We suppose the BCP obtain energy by frication and make the temperature to reach Tg, so BCP become melts. In the second part, we write BCP on the substrate and make BCP film uniform. We write BCP on wafer or prewetted substrate in this experiment. We can find that BCP is easy to nucleate. We guess the reason is the effect of BCP cohesion is larger than the interaction between BCP and substrate. We write BCP on PMMA to make stronger interaction between BCP and PMMA. BCP film can be written uniformly on PMMA and the thikness is smaller then 5 nm. In the final part we observe the micro phase separation. We find micro phase separation in one experiment. From literature review, there is no phase separation when thikness is smaller than 15 nm. This result is so surprised. It is too pity that experiment is unstable, the result has no repetition

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40

Lai, Yu-Hung y 賴育宏. "Formation of Nanoporosity through Degradation of Poly(methylmethacrylate) in the PE-b-PMMA Block Copolymer". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/85017566957265890353.

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碩士
國立中正大學
化學工程所
96
A PE-b-PMMA has been formed via hydrogenation of PB-b-PMMA which was synthesized via anionic polymerization. To achieve the desired morphology, we have blended a homo-polyethylene into PE-b-PMMA enabling the PMMA phase to self-assemble as cylinders. The PE-b-PMMA/homo-polyethylene has been cast into films under various temperatures, rotation speeds, and annealing durations. Afterwards, the PMMA microdomains are cleaved via UV-Light degradation and removed by acetic acid resulting in the formation of a nanoporous PE film. SEM and AFM images indicate that the resulting PE film has a pore size of 25~50 nm and thus is potentially useful for photonic crystal or fuel cell applications.

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41

Liu, Chia-Hong y 劉家宏. "Adding Inorganic Nano-Silica Particles into the Organic PS Phase of PS-b-PMMA Diblock Copolymer". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/76845319101442466825.

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碩士
國立中正大學
化學工程所
97
Using the self-assembly characteristic of diblock copolymer and its unique phase separation morphology, we blend the surface modified nano-silica into the diblock copolymer in order to disperse these nano-particles selectively and uniformly in polymer film. In this study, the diblock copolymer (PS-b-PMMA) and short chain PS capped with coupling agent 3-CPTMOS were prepared firstly via anionic polymerization. Then the capped PS was bonded with nano-SiO2 by the sol-gel reaction. Finally, various amounts of PS-SiO2 was blended into PS-b-PMMA and spin-casted to films. After annealing the morphology of these films was thoroughly studied by AFM and SEM.

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42

Tien-Ching, Lin. "Synthesis and Morphology Characterization of Amphiphilic Block Copolymer, polystyrene-block-poly[3-(trimethoxysilyl propyl methacrylate] (PS-b-PMSMA)". 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2707200615220700.

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43

Lin, Tien-Ching y 林典慶. "Synthesis and Morphology Characterization of Amphiphilic Block Copolymer, polystyrene-block-poly[3-(trimethoxysilyl propyl methacrylate] (PS-b-PMSMA)". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/02635813499962937989.

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碩士
國立臺灣大學
高分子科學與工程學研究所
94
Amphiphilic block copolymers have been extensively studied in recent years. They can not only be prepared by versatile synthetic approaches but also have multiple morphologies generated from its different chemical interaction between two blocks or environment. In this thesis, the synthesis and morphologies of amphiphilic block copolymer, polystyrene-block-poly[3-(trimethoxysilyl)propyl methacrylate] (PS-b-PMSMA), are reported. Two issues will be addressed in this thesis:： (1) Control of molecular weight and its distribution, chain length and its ratio by the reaction conditions of atom transfer radical polymerization (ATRP); (2) correlation of morphology of PS-b-PMSMA with PS/or PMSMA selective mixed solvent. In this study, the homopolymers of polystyrene(PS), poly[3-(trimethoxysilyl)propyl methacrylate](PMSMA), and diblock copolymer of PS-b-PMSMA were prepared by ATRP using alkyl bromide (MBrP) and CuBr/N,N,N’,N”,N”-pentamethyldiethylene -triamine (PMDETA) as initiator and catalyst, respectively. Various reaction composition and reaction condition were used to optimize the molecular weight and its distribution, including catalyst/initiator ratio, temperature, monomer and ligand concentration, and solvent content. The experimental results suggested the following conclusions for controlling the molecular weight and its distribution : (1)Increasing the concentration of CuBr and monomer or decreasing the content of solvent enhanced the polymerization rate and maintained the narrow molecular weight distribution; (2) Enhancing the concentration of CuBr2 would decrease polymerization rate but also decrease the molecular weight distribution; (3) enhancing reaction temperature could not only increase the polymerization rate but also enhance the initiation efficiency and obviously decrease the molecular weight distribution. The polydispersity indexes (PDI) of the obtained PS macroinitiators were controlled less than 1.1, and the PDI of both PMSMA and PS-b-PMSMA were controlled lower than 1.4. However, when the polymer molecular weight higher than 30000, the propagation of PMSMA would become difficult due to the high viscosity of polymerization reaction and steric hindrance from the polymer chain. Thus, the PDI would be out of control at such high molecular weight polymer. The morphology of PS-b-PMSMA in different solvent systems was studied by TEM. The experimental results suggested various kinds morphology from the following solvent systems: (1) The morphology observed at anisole /PMSMA selective solvent (1-Methoxy-2-propanol, MOPO) system are mainly spheres due to the strong repulsion between PMSMA corona blocks or the high Tg PS blocks at the core of micelle. (2) The morphology observed in anisole/PS selective solvent( ethyl acetate, EA) system is more versatile than PMSMA solvent/anisole system. The coexistence of sphere and rod-like micelles was observed at the anisole/EA mixed solvent with volume ratio of 50/50, and vesicles are observed at 25/75, respectively. At this system, surface energy between solvent and core is considered as the major driving force to determine size and shape of micelles. The χ increases as the selective solvent content increases and results in an enhancing the surface energy, which leads to decrease the unit surface area (a0). Hence, with the increase of packing parameter P(=v/a0l), the micelle change form sphere (P=1/3), rod-like micelle(P=1/3~1/2), to vesicle(P=1/2~1) were observed in the mixed solvent system. (3) The effect of block length on the morphology was found less significant than the effect of selective solvent. The only difference observed is the morphology size, e.g., PS123-b-PMSMA42 spheres (60nm) are larger than the PS95-b-PMSMA42 spheres size (40~50nm) due to the longer PS chain length. (4) PMSMA block was found hydrolyzed spontaneously. When a basic catalyst was added into PS-b-PMSMA solution, the vesicles formed from self-assembly of hydrolyzed polymers would be fixed, as observed by TEM. 1HNMR and FTIR analysis also suggested the crosslink of PMSMA chains. The present study suggests that the morphologies of PS-b-PMSMA could be tuned by different solvent polarity, block length or the addition of hydrolysis catalyst.

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44

CHEN, CHIEH-CHUN y 陳玠均. "Patterning of PDEAEMA-co-PMAA copolymer brush on silicon substrate for application of Yersinia pestis detection with homemade laser system". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/16571535327494273194.

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碩士
國立臺灣科技大學
材料科學與工程系
105
In this study, patterned PDEAEMA-PMAA co-polymer brushes were grafted from silicon substrates with VLSI processes. First at all, photoresists were patterned as line arrays with lithography process. Sequentially, the surfaces were treated with oxygen plasma to generate line patterns of hydrophilic groups. Halogen groups were immobilized through the line patterns of hydrophilic groups as initiators of ATRP. Finally, PDEAEMA-PMAA co-polymer brushes were grafted from the line patterns to generate polymer gratings. The composition of the surface at each stage of fabrication were verified with X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy(FT-IR). In addition, we designed a laser system to observe the intensity of reflective diffraction. Thickness of the polymer brushes were analyzed with atomic force microscopy (AFM) and the laser system.

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