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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Influence of the Precursor on the Synthesis Mechanisms of Primary Amine-based Plasma Polymers: From Plasma Diagnostic to Film Chemistry and Applications

Denis, Laurent 17 December 2009 (has links)
Primary amine-based plasma polymer films (PPF) attract an increasing interest due to their potential applications as platforms to support cell growth and biomacromolecule immobilization. It has been demonstrated that the biological response of these films is correlated to their primary amine content (%NH2). Control and optimization of the process are thus very important requirements. However, despite the abundant literature related to this attractive technology, plasma polymerization remains very complex so that strong efforts are still needed to understand the relationship between the plasma chemistry and the PPF characteristics. The main part of this work describes the pulsed plasma polymerization of two isomeric precursors, namely allylamine and cyclopropylamine, with the aim to study the influence of the precursor on the plasma and the PPF physico-chemistries. The systems have been compared in similar conditions of mean power injected in the discharge (Pmean). Both experimental and theoretical approaches have been used to shed light on the process. Taking into account the electron energy in the plasma, differences between allylamine and cyclopropylamine plasma chemistries have been rationalized with the help of Density Functional Theory calculations. It is demonstrated that %NH2 can be increased by an appropriate choice of the precursor and the experimental conditions. Indeed, the use of cyclopropylamine can yield to PPF with a larger %NH2 compared to allylamine due to a preferential opening of the ring structure in the plasma. A method is also proposed to discriminate the PPF according to their cross-linking density (÷). While it appears to be independent of the chemical structure of the precursor, ÷ is observed to significantly vary with Pmean. The PPF have further been investigated with the aim to better understand the phenomena taking place when immersed in liquid medium, an essential step for biological applications. The results show that the decrease in the PPF thickness (Äd), conventionally observed upon immersion, directly depends on Pmean; the higher Pmean, the lower Äd. For the first time to our knowledge, the present work allows to unambiguously attribute this phenomenon to an increase of ÷ with Pmean. Furthermore, thanks to the analysis of the resulting solutions, the data give a new insight into the PPF behavior in liquid medium, suggesting that Äd is mostly related to a reorganization of the PPF network and not to material dissolution as usually claimed. Finally, some preliminary experiments indicate that the PPF can be used to support muscle cell culture; the performances of the PPF-coated materials reveal to be at least similar to those of the standard surfaces.
42

Liquid phase plasma technology for inkjet separation

Jordan, Alexander Thomas 31 January 2013 (has links)
Currently most deinking technologies are dependent upon flotation and dissolved air flotation (DAF) technology in order to separate inkjet ink from fiber and water. Much of this technology is based on ink that is extremely hydrophobic. This made flotation and DAF very easy to use because the ink in the water would very easily move with the air in flotation and be brought to the surface, after which the ink can be skimmed and the pulp can be used. Now that small scale printing has become the norm, there has been a move to high quality, small scale printing. This involves the use of a hydrophilic ink. Hydrophilic ink cannot be easily separated from water and fiber the same way the hydrophobic ink can be. With low concentrations of hydrophilic ink in the process water stream, it can be absorbed into the process but as the hydrophilic ink concentration rises alternative methods will be needed in order to separate inkjet ink from water. One solution is to find a method to effectively increase ink particle size. This will enable the ink particles to be filtered or to have an increase ecacy of removal during flotation. In this thesis, one solution is discussed about how electric field and electric plasma technologies can be used to increase particle size and help purify process water in recycle mills. This plasma treatment can very effectively bring ink particles together so that they may be separated by another method. There are two methods by which this may take place. One is polymerization and the other is electro-coagulation. These processes can work side by side to bring ink particles together. This plasma treatment process creates free radicals by stripping off hydrogen atoms from surrounding organic matter. These free radicals then react with the high alkene bond content within the ink to create a very large covalently bonded molecule. This is the new mechanism that is being investigated in this thesis. The other action that is taking place is electro-coagulation. Plasma treated ink can be filtered out using a cellulose acetate or cellulose nitrate membrane or they can be filtered using paper or fiber glass filters as well. The extent at which these can be filtered out is dependent on the size of the pores of the filter. In this study, it was shown that the plasma treatment was able to clean water with a fairly small amount of energy. It was also found that treatment time and concentration had very little eect on the outcome of the treatment ecacy. One factor that did have an effect was the pH. At very high pH values the process became noticeably less eective. The high pH essentially eliminated the electro-coagulation aspect of the treatment process and also hurt the polymerization aspect as well because of lower amount of hydrogen atoms available for the plasma to create free radicals. A model of the process was used to try to give the reader an idea of the ecacy that the process would have in an industrial scale process. The model assumes that two types of ink particles exist. One is ink that has a radical and another in which the ink does not have a radical. The model also assumes that if ink is at all polymerized, ink is filtered out with the 0.8 micron filter. The model assumes three reactions; initialization, propagation and partial termination. The partial termination is a result from the general chemical structure of ink. Ink has many double bonds in its general structure which makes termination very unlikely to occur, so the model assumes that on average when two radials interact that only one is eliminated. This model is only supposed to give the reader an idea of the ecacy of the process. The numbers provided in the model will change very significantly in a different system. The evidence behind polymerization aspect of the process comes from two main sources. One is the small molecule analysis from methanol after being exposed to the plasma and the other from the plasma being exposed to allyl alcohol. The small molecule analysis shows that the process generates free radicals on organic molecules. Methanol was exposed to the plasma and then the resulting GC/MS analysis showed that 1,2-ethanediol was present, this showed that the electric discharge process was able to create free radicals on organic molecules in the liquid phase. Using a similar process the plasma discharge process was exposed to a mixture of allyl alcohol, water and propanol and water in two separate experiments. The difference between these two molecules is an alkene bond that is between the carbon two and carbon three atoms. The particle size of both samples was then analyzed and it was shown that the solution with allyl alcohol had an average particle size about an order of magnitude larger than the solution with propanol in it. Because of all the evidence discussed here and in the rest of the thesis we believe that the plasma treatment of ink has both polymerization and electro-coagulation aspect. This process could also be a potential solution to the water soluble ink problem that will soon face the recycling industry.
43

Characterization of plasma-polymerized polyethylene glycol-like films

Pathak, Shantanu Chaturvedi 25 September 2008 (has links)
A parallel-plate capacitively-coupled plasma deposition system was designed and built for the growth of polyethylene glycol-like films. Deposition rate, bonding structure and dissolution and swelling behavior was characterized as a function of input RF power, reactor pressure and substrate temperature to provide information on the relationship between input plasma parameters and film properties. For the conditions studied in this thesis, deposition rates increased at increasing input powers and operating pressures and decreasing substrate temperatures. The PEG-like coatings resembled higher molecular weight solution-polymerized PEG films with a higher crosslinked structure. Manipulation of plasma deposition conditions allowed control of film crosslink density and resulted in tunable dissolution and swelling properties of the PEG-like polymer. At higher applied powers, lower operating pressures, and higher substrate temperatures, films had a higher crosslink density, thus leading to slower dissolution rates and smaller extents of swelling. Void space openings of swelled-state, PEG-like films were determined using electrophoretic drift and diffusion-controlled transport of fluorophore-tagged PAMAM dendrimers into the bulk of the coating. PAMAM dendrimers were used because of their well-defined sizes and negatively-charged succinamic acid surface groups as a means to probe pore sizes of the plasma films. It was estimated that the upper bound of pore size diameters in the plasma polymer was approximately equal to ~5.5-6.0 nm. Positron annihilation lifetime spectroscopy was used to determine average pore sizes and was estimated to equal ~0.60-0.65 nm.
44

Microstructures and multifunctional microsystems based on highly crosslinked polymers

Singamaneni, Srikanth. January 2009 (has links)
Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Tsukruk, Vladimir; Committee Member: Gall, Ken; Committee Member: Griffin, Anselm; Committee Member: Jang, Seung Soon; Committee Member: Thio, Yonathan. Part of the SMARTech Electronic Thesis and Dissertation Collection.
45

Metal plasma immersion ion implantation and deposition using polymer substrates

Oates, Thomas William Henry. January 2003 (has links)
Thesis (Ph. D.)--University of Sydney, 2004. / Title from title screen (viewed 5 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science. Degree awarded 2004; thesis submitted 2003. Includes bibliographical references. Also available in print form.
46

Caracterização estrutural e propriedades óticas e mecânicas do diglime polimerizado a plasma

Fernandes, Rodrigo Sampaio [UNESP] 24 May 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-05-24Bitstream added on 2014-06-13T19:37:20Z : No. of bitstreams: 1 fernandes_rs_me_guara.pdf: 1399605 bytes, checksum: db34bbb596dd0b00a21efd7933e1f803 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Esta dissertação de mestrado trata do estudo da caracterização estrutural, e de propriedades óticas e mecânicas do dietilenoglicoldimetiléter (DIGLIME) polimerizado via plasma. Este tipo de plasma produz filmes poliméricos com características físicas, químicas e biológicas semelhantes àquelas observadas em poli(óxido de etileno)- (PEO) e polietileno-glicol (PEG), que são polímeros produzidos através de processos químicos convencionais. Os polímeros a plasma foram obtidos usando descargas de rádio-freqüência operando em 13,56 MHz. Os parâmetros do processos de deposição utilizados foram potência de 10 a 40W e pressão de operação de 120 a 440 mTorr. A estrutura molecular dos polímeros foi estudada por espectroscopia infravermelha. De acordo com os resultados obtidos, baixas pressões e potências de RF produzem filmes poliméricos com características tipo PEO. A tensão mecânica residual nos filmes poliméricos foi investigada pelo método da deflexão de um feixe de laser. Os resultados indicaram tensões compressivas em todos os polímeros e boa estabilidade em função do tempo de envelhecimento. As propriedades óticas dos polímeros a plasma, como coeficiente de absorção, gap ótico e índice de refração foram investigadas através de espectroscopia ultravioleta-visível. O índice de refração calculado é próximo de 1,5 e o gap ótico decresce de 5,0 para 3,5 eV quando a potência de rádio-freqüência é aumentada de 10 para 40W . / This Mastering Dissertation deals with the study of structural characterization mechanical and optical properties of the diethyleneglycoldimethylether (diglime) polymerized by plasma. This kind of plasma produces polymer films with interesting physical, chemical and biological characteristics likely those observed in polyethylene-oxide (PEO) and polyethylene-glycol (PEG) that are polymers produced by conventional chemical processes. The plasma polymer films were obtained using 13.56 MHz radio-frequency discharges. The process parameters were RF power from 10 to 40W and operation pressure from 120 to 440 mTorr. The molecular structure of the films was investigate by infrared spectroscopy. According to the obtained results, low pressures and RF power discharges, produce polymer films with PEO-like characteristics. The residual mechanical stress in the films was investigated by the laser beam deflection method. The results indicated compressive stresses in all films and good stability as a time function. The optical properties of the plasma polymers such as absorption coefficient, optical gap and refractive index were investigated using ultraviolet-visible spectroscopy. The calculated refractive index is near 1.5 and the optical gap decreases from 5.0 to 3.3 eV as the RF power is increased from 10 to 40W.
47

Uso de filmes obtido pela polimerização por plasma de tetraetilortossilicato na fabricação de dispositivos miniaturizados. / Use of films obtained by tetraethoxysilane plasma polymerization for production of miniaturized devices.

Rodrigo Amorim Motta Carvalho 11 March 2009 (has links)
Os antigos e já bem desenvolvidos dispositivos para tratamentos e/ou análise de amostras têm sido grandemente estudados para novas adaptações, devido à importância de se construir sistemas miniaturizados. A obtenção destes sistemas miniaturizados baseia-se não apenas na construção ou metodologia, mas pode depender de modificação superficial para melhoria de desempenho ou diferenciação de aplicações. A modificação de superfície com filmes finos obtidos por plasma é bem conhecida na Microeletrônica. Assim, este trabalho teve como objetivo avaliar a possibilidade do uso da modificação superficial pela produção de filmes finos a partir da polimerização por plasma de Tetraetilortossilicato, TEOS - para fabricação de estruturas miniaturizadas, principalmente para retenção e/ou pré-concentração, em pré-tratamento de amostras ou mesmo para proteção de sistemas de detecção. A metodologia utilizada correspondeu a testes destes filmes em canais ou membranas seletivas. Quanto aos canais utilizou-se geometria planar e/ou tridimensional; as membranas foram testadas em geometria planar. Microcanais tridimensionais, usados tanto em fase gasosa como líquida, foram testados para determinação de retenção/pré-concentração de compostos orgânicos voláteis. Para testes de retenção de compostos inorgânicos em fase líquida (água como solvente) utilizaram-se não só microcanais, tridimensionais ou planares, como também membranas. Proteção de sistemas de detecção exigiu o uso de geometria plana. Quanto ao filme a base de TEOS, este foi testado imediatamente após a deposição, após envelhecimento por no mínimo seis meses ou após exposição a condições adversas como a que levam à hidrólise de radicais orgânicos presentes no filme, ou mesmo após hidrofobização da superfície, por exposição à Hexametildissilazana, HMDS. A construção de dispositivos, com canal planar ou tridimensional, permitiu o desenvolvimento de diferentes sistemas de tratamento, e respectivos métodos de análise, para separação, retenção e pré-concentração de amostras. Os resultados obtidos demonstraram que um dispositivo com canal tridimensional, tratado pela deposição a base de TEOS e posterior hidrólise do filme, permite a retenção de íons e formação de clusters de cobre, em fase líquida. Do mesmo modo, permite a separação de compostos orgânicos em pequena concentração e retenção de compostos polares, em fase gasosa. Para dispositivo planar foi observada a separação de íons através de estrutura plana, similar às utilizadas em eletrocromatografia. Os estudos processados permitiram propor pequenos dispositivos, de baixo custo e fabricação simples, que podem ser facilmente implantados na área de análises. Assim, o canal tridimensional testado tem comportamento semelhante ao de uma pré-coluna. Como é de simples construção e sua entrada e saída possui similaridades com uma pré-coluna comercial, a instalação desta pré-coluna em um cromatógrafo miniaturizado requererá poucas etapas. Essa nova pré-coluna também apresentaria grandes vantagens se fosse adicionada imediatamente antes de detectores não específicos, tais como os usados no nariz eletrônico. Pela diminuição de compostos presentes na mistura, as dificuldades de análise dos resultados igualmente decresce, pela maior facilidade de criação de padrões. / The long-established and well-known devices for sample pretreatment and/or analysis have been widely studied to new adaptations due to the miniaturization trend. The production of these miniaturized systems requires not only new approach on manufacturing and methodology but also depends on surface modification for performance improvement or new applications development. Surface modification using plasma-produced thin films is well established in Microelectronics. Therefore, the aim was to evaluate the use of Plasma polymerized Tetraethylorthosilicate surface modification on manufacturing of miniaturized structures. The main use of such a modification is on devices for sample pretreatment - retention, pre-concentration, or even for protecting detection system surface. The methodology carried out tested these thin films in channels and selective membranes. Whereas channels used three-dimensional and planar geometries, membranes were tested only with planar geometries. Three-dimensional microchannels, used in gaseous or liquid phase, were tested for retention/preconcentration of volatile organic compounds (VOCs). Retention of inorganic compounds in aqueous liquid phase was tested using not only three-dimensional and planar microchannels but also membranes. Protection of detection systems required planar geometry. TEOS thin film was tested after: deposition, ageing for several months; exposition to severe environmental conditions that leads to hydrolysis of organic radicals present in the film; surface hydrophobization due to hexamethyldisilazane, HMDS, exposure. Manufacturing of miniaturized three-dimensional and planar devices leads to some solutions on sample pretreatment and respective analysis methodology. These devices can be used for separation, retention and pre-concentration. The results pointed out that a threedimensional microchannel with plasma deposited TEOS film previously hydrolyzed allows ion retention and clusters formation in a copper aqueous solution. Furthermore, in gaseous phase, VOCs in small concentration can be separated whereas polar compounds can be retained. Planar device allows separation of inorganic ions in a structure similar to the ones used in electrochromatography. Small and low-cost devices are thus here provided, which can easily be machined and are very useful in the chemical analysis field. The three-dimensional microchannel presented behavior similar to the one of a chromatographic pre-column. This microchannel can also be easily adapted to a miniaturized chromatograph. Other possible use is in sample pretreatment, coupled ahead of non-specific detectors, such as electronic noise arrays, since it can decrease the numbers of compounds to be detected and, consequently, reduce drawbacks concerning results analysis.
48

Elaboration par plasma froid basse pression de revêtements polymères protecteurs de fibres organiques et inorganiques

Einig, Antinéa 03 October 2013 (has links)
L’allègement des structures combinée a l’augmentation de leurs propriétés mécaniques et électriques est un des axes d’innovation dans le domaine des composites à hautes performances. Certains de ces matériaux emplois des matrices organiques à renforts carbones. Une voie de recherche privilégiée est l’utilisation et l’intégration de nanomatériaux aux composites. Ainsi des nanotubes de carbone sont greffés à la surface des fibres de carbone, créant une fibre hybride. Pendant le processus industriel subi par la fibre, des nanotubes sont susceptibles d’être relâchés et de provoquer la dégradation des propriétés de la fibre. La dimension nanométrique de ces particules les rend plus performant que les matériaux conventionnels mais constitue un risque potentiel pour la santé de l’être humain. Pour conserver les nanotubes sur la fibre, un revêtement polymérique protecteur est ajouté à la fibre hybride. Dans le cadre de cette thèse, ce revêtement est déposé par polymérisation plasma sous vide d’un monomère. Les monomères d’acide acrylique et d’acétylène agissent avec les paramètres de dépôt sur l’interface entre les fibres et la matrice, et donc sur les propriétés mécaniques du composite. L’évolution de cette interface est caractérisée par l’énergie de surface du dépôt sur substrats modèles puis sur fibre hybride. Les revêtements issus des deux monomères assurent la protection des nanotubes, améliorent l’interface entre la fibre et la matrice, tout en conservant le gain de conduction apporte par le greffage des nanotubes. L’addition d’une étape de traitement plasma non polymérisable, avant ou après le dépôt du polymère, peut améliorer les propriétés interfaciales par rapport aux fibres hybrides. / Innovation areas in high performance composite are based on structure lightening combined with mechanical and electrical enhancement. Carbon reinforced organic matrix is widely used for composite applications. Nanomaterial’s incorporation appears among the ways of improvement. In this study, carbon nanotubes are grafted on carbon fibers’ surface to create a hybrid fiber. However, handling hybrid fibers may lead releasing CNT, weakening fiber properties and unwilling health risk. A protective layer is then required for properties saving and for safety purpose. In our work, a coating is deposited by low pressure plasma polymerization of organic monomer: acrylic acid or acetylene. Monomer deposit parameters influence cohesion at the interface between fiber and matrix by means of physical and chemical interactions. We show from results observed at microscal that macro mechanical properties of the final composite are also modified. Coating is characterized by means of surface energy calculation on model substrate. It allows choosing coating properties and plasma treatment conditions to be applied to hybrid fibers. A protective coating is obtained from the two monomers on nanotubes and increases mechanical properties at the fiber/matrix interface. The deposit does not spoil electrical conductivity of hybrid fiber. Addition of pre or post plasma treatment before or after coating may improve in some case mechanical properties of composite within the interface between protected hybrid fiber and matrix compared to uncoated one.
49

Fabricação e caracterização de Guia de Onda Polimerica a base de PMMA modificado por plasma de CHF3 / Polymeric optical waveguides fabricated by plasma fluorination process

Giacon, Virginia Mansanares 12 August 2018 (has links)
Orientador: Julio Roberto Bartoli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-12T18:45:17Z (GMT). No. of bitstreams: 1 Giacon_VirginiaMansanares_D.pdf: 2629036 bytes, checksum: 8a24595beeaf5a6bb205d496d70477a8 (MD5) Previous issue date: 2007 / Resumo: Dispositivos ópticos poliméricos são utilizados em comunicações e interconexões ópticas devido à intrínseca versatilidade da estrutura molecular polimérica, que permite modelagem do índice de refração dos materiais utilizados para a produção de núcleo e casca, além da facilidade de processamento e capacidade de moldagem desses materiais. O PMMA (poli [metacrilato de metila]) por apresentar alta transparência, possui as melhores propriedades ópticas, quando comparado à outros polímeros, além de boas propriedades mecânicas, sendo o seu uso bastante comum como material de núcleo em dispositivos ópticos. Nos dispositivos ópticos, como guias de ondas, um baixo índice de refração é necessário para o material de casca e é usualmente obtido com polímeros fluorados. Neste trabalho, guias de ondas planares foram fabricados com filmes ópticos poliméricos em substrato de silício. A casca, um polímero parcialmente fluorado de aproximadamente 0,6 mm de espessura, foi obtida através da polimerização por plasma com CHF3, utilizando um reator de placas paralelas de 13,56 MHz. O núcleo de PMMA foi produzido por spin coating. O índice de refração do núcleo e casca é de 1,49 e 1,40 respectivamente, medidos por elipsometria e acoplamento por prisma. Os filmes ópticos fluorados por plasma foram caracterizados por FTIR-ATR e interferômetria. Guias de ondas poliméricos com diferentes larguras, de 10 a 100 mm, foram moldados através de fotolitografia seguida por RIE usando uma máscara de fotolitografia de cromo. A caracterização óptica foi feita utilizando um laser (l= 632,8 nm) através de acoplamento fibra-guia. Atenuação do sinal da luz transmitida foi de 3,6 dB/cm para um guia de 100 mm de largura e aproximadamente 15 mm de espessura. Essa atenuação provavelmente possui uma significativa contribuição do acoplamento fibra-guia, com forte efeito nas perdas por inserção e espalhamento devido à rugosidade das superfícies laterais (horizontal e vertical). Ainda assim, este guia polimérico com casca de material fluorado, produzida pelo processo de polimerização por plasma, apresenta-se promissor. / Abstract: Polymeric optical devices have been studied in communication and interconnection optics due to the intrinsic versatility of polymers molecular structure, that allows advantageous refractive index modeling for core and cladding, and also to their easy fabrication process or patterning capability. PMMA, polymethylmetacrylate, shows the best optical properties among transparent polymers, being a very common core material for optical devices. Low refractive index is a requirement for cladding material and it is usually achieved with fluorinated polymers. Plasma of fluorocarbons are frequently used either for etching of substrates in microelectronic technologies or for deposition of plasma polymerized fluorinated monomers films. In this work, planar polymeric waveguides were fabricated on silicon substrate. The cladding was a fluorinated polymer (0.6 mm) produced by CHF3 plasma polymerisation (parallel plate reactor, 13.56 MHz) and the core was a PMMA film prepared by spin coating. The refractive index of the PMMA film and fluorinated film were 1.49 and 1.40, respectively, characterized by ellipsometry and metricon prism coupler. The plasma fluorinated optical films were characterized by FTIR-ATR and interferometer. The polymeric waveguides with different widths (from 10 to 100 mm), using the chrome mask, were patterned by UV photolithography and O2 plasma etching in Reactive Ion Etching process. The optical characterization was done coupling a laser beam (l=633nm), fibre-tofibre coupling method, using a multimode optical fibre. The propagation loss, is about 3.6 dB/cm at l=633 nm. Lower losses could be achieved by a more careful control of the RIE process and cleavage process. Despite of high optical losses, this plasma fluorinated polymer presents a potential processing alternative for cladding of polymeric optical waveguides. / Doutorado / Ciencia e Tecnologia de Materiais / Doutor em Engenharia Química
50

Contrôle des propriétés mécaniques par polymérisation plasma pour des surfaces innovantes antibactériennes / Control of mechanical properties by plasma polymerization for innovative antibacterial surfaces

Veuillet, Mathieu 09 March 2017 (has links)
Le contrôle de la formation des biofilms est un enjeu économique majeur pour un grand nombre de secteurs économiques comme la distribution d’eau potable. De nombreuses voies sont explorées pour contrôler leur développement. Ces travaux proposent d’explorer la possibilité de prévenir l’adhésion bactérienne en exploitant les propriétés mécaniques de surface de films minces obtenus par polymérisation plasma basse pression à partir de deux précurseurs : le 2-(diméthylamino)éthyl méthacrylate (DMAEMA) et l’hydroxyéthyl méthacrylate (HEMA). Les résultats des caractérisations des propriétés de surface (AFM, IR, XPS, mouillabilité, nanoindentation par AFM) de ces films minces ont montré qu’il est possible de contrôler les propriétés mécaniques des dépôts polymères plasmas, notamment du HEMA, tout en conservant des propriétés chimiques similaires. Les propriétés d’anti-adhésion bactérienne des films minces HEMA ont été évaluées en utilisant une souche Escherichia coli SCC1 au cours de culture statiques et dynamiques. Ces cultures ont montré que lorsque les propriétés mécaniques de surface sont de l’ordre de 600kPa, elles induisent des propriétés d’anti adhésion et une forte mobilité des bactéries. Sous flux, ces propriétés sont exaltées avec aucune bactérie détéctée au bout de deux heures. Afin de pérenniser cette solution sur plusieurs dizaines d’années, un système multicouche a été développé afin de conduire à un renouvellement périodique des propriétés antibactériennes. De plus, cette stratégie a été développée par polymérisation plasma à pression atmosphérique dans l’optique de son industrialisation. / Control of biofilm formation is a major economic challenge for a large number of economic sectors such as the distribution of drinking water. Many strategies have been explored to fight against their development. This work proposes to explore the possibility of preventing bacterial adhesion by playing with mechanical surface properties. To do this, low pressure plasma polymerization of two precursors: 2- (dimethylamino) ethyl methacrylate (DMAEMA) and hydroxyethyl methacrylate (HEMA) has been explored. The results of surface characterizations (AFM, IR, XPS, wettability and AFM nanoindentation) of these thin films showed the possibility to obtain different mechanical properties in wide range (kPa to MPa) with similar chemical surface properties. Bacterial anti-adhesion properties of these films were evaluated using an Escherichia coli SCC1 strain during static and dynamic cultures. These results showed that mechanical surface properties around 600 kPa induced very good bacterial anti-adhesion properties and also revealed mobility of bacteria on the surface. Under flow, these properties were highlighted with almost no bacterial detected after two hours. In order to prolongate the life time of these properties, multilayer system has been proposed and synthesis of these plasma polymer multilayer has been studied at atmospheric pressure for industrial scale up.

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