Дисертації: "Textile nanoparticles"

1

Panwar, Kamlesh. "Janus particles for textile applications." Thesis, IIT Delhi, 2016. http://localhost:8080/xmlui/handle/12345678/7219.

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Wilhelm, Manon. "Development of SERS substrates of metal nanoparticles and textile fibers." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15336.

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Mestrado em Ciência e Engenharia de Materiais
Noble metallic nanostructures are well-known materials that present interesting physical and chemical properties, especially the surface plasmon resonance involved in the surface-enhanced Raman signal (SERS) of molecules adsorbed at the metal surface. Since its discovery, the SERS method is a highly studied analysis technique that allows detecting molecules at very low concentration. Numerous works are currently leaded to develop more efficient SERS substrates to lower the detection limit. Also, the development of more convenient substrates, eventually coupled with portable Raman technology is promising for the detection of low concentrated molecules in multiple domains, as for example the detection of dyes. This report presents the study of new nanocomposites with texile fibers for their use as SERS substrates. A literature review about natural fibers, metallic nanoparticles, nanocomposites and SERS technique will first be presented to contextualize this research. Then, several combinations of composites were prepared with natural fiber matrix of linen, silk or cotton. To prepare the nanocomposites, gold and silver nanoparticles were synthesized by the citrate method and have a mean size of respectively 14 nm and 86 nm. Then, three techniques of synthesis are used to produce the nanocomposites; namely the blending of fibers and metal colloids previously prepared, with and without modification of the fiber’s surface with polyelectrolytes, and the in situ synthesis of the particles in presence of the fibers. The nanocomposites were then characterized by several techniques such as scanning electron microscope, X-ray diffraction and optical measurements. The molecular probe used to evaluate the quality of the composites as SERS substrates was methylene blue (MB). This molecule has a strong SERS signal and is a dye frequently used in textile industry. Mapping studies of the composites were performed, using Raman confocal microscopy with MB as molecular probe. These studies allowed monitoring the distribution of the metallic nanoparticles at the fiber’s surface, as well as the presence of MB. The results showed that the detection of MB through this technique strongly depends on the type of nanocomposite, knowing that the composites with silver presented a better SERS signal of MB than the similar material with gold. Particularly, the composites of linen and silver presented very promising results as SERS substrates for the detection of MB.
As nanopartículas de prata e ouro são materiais que exibem propriedades físicas e químicas muito interessantes, nomeadamente as que se encontram associadas a efeitos de superfície como por exemplo na obtenção de espetros de Raman de moléculas adsorvidas na superfície de metais, originando sinais por intensificação por superfície (SERS: Surface-enhanced Raman scattering). Desde a sua descoberta, o efeito de SERS tem sido aproveitado em técnicas de análise e deteção de analitos em concentração muito baixa nas respetivas soluções. Um aspeto muito relevante em termos de desenvolvimento de novos materiais é a investigação de substratos mais eficientes para SERS. Além disso, o desenvolvimento de substratos mais convenientes, eventualmente acoplados a instrumentos de Raman portáteis é também promissor para a deteção de baixas concentrações de moléculas em múltiplas áreas, como por exemplo a deteção de corantes. Esta dissertação de Mestrado apresenta estudos em novos nanocompósitos à base de fibras têxteis e nanopartículas metálicas, tendo em vista a sua utilização como substratos para SERS. Primeiramente é apresentada uma revisão bibliográfica sobre fibras naturais, nanopartículas metálicas, nanocompósitos e a técnica de SERS, de modo a contextualizar o trabalho de investigação. Este envolveu numa primeira fase a preparação de nanocompósitos à base de fibras naturais, tais como o linho, a seda e o algodão. Utilizaram-se para o efeito nanopartículas coloidais de Au e Ag obtidas pelo método de citrato, com tamanho médio de 14 e 86 nm, respetivamente. Seguidamente, exploraram-se três técnicas preparativas para obter os nanocompósitos, nomeadamente a mistura das fibras e os coloides metálicos previamente preparados, com e sem modificação prévia da superfície das fibras com polieletrólitos e, ainda, a síntese in situ das nanopartículas na presença das fibras. Os nanocompósitos foram caracterizados por diversas técnicas, tais como microscopia eletrónica de varrimento, difração de raio-X e espetroscopia eletrónica. Em particular, realizaram-se estudos detalhados de espetroscopia de Raman explorando o efeito de SERS e usando o azul de metileno (MB) como analito. Esta molécula origina um sinal de SERS intenso sendo um corante frequentemente utilizado na indústria têxtil. Realizaram-se ainda estudos pioneiros no mapeamento destes materiais, usando o MB como sonda molecular, utilizando microscopia confocal de Raman. Estes estudos permitiram igualmente investigar a distribuição das nanopartículas metálicas na superficie das fibras bem como a presença do MB. Os resultados indicaram que a deteção de MB por esta técnica depende fortemente do tipo de nanocompósito, sendo que os nanocompósitos contendo prata apresentaram melhor sinal de SERS para a deteção do MB em comparação com os materiais análogos de ouro. Em especial, os nanocompósitos de linho e prata originaram resultados muito promissores como substratos de SERS na deteção do MB.

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3

Messaoud, Mouna. "Fonctionnalisation anti-bactérienne passive ou active de tissus textiles par voie sol-gel ou photochimique - L'association du TiO2 et de la chimie douce." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00584376.

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Au cours de cette thèse, plusieurs approches de fonctionnalisation anti-bactérienne passive, de type"bactériostatique" utilisant des espèces hydrophobes, et active (selon un standard ISO), de type"bactéricide" utilisant des nanoparticules d'argent métallique ou des espèces à base d'ammoniumquaternaire, ont été testées sur des tissus textiles. Des solutions liquides ont été élaborées par voie sol-gelet photochimique, en association ou non. Elles ont tout d'abord été caractérisées d'un point de vuephysico-chimique, morphologique et structural, afin d'optimiser leur formulation et les caractéristiquesdes espèces en solution vis-à-vis de différents cahiers des charges industriels. Ce travail d'optimisation aen particulier conduit à des solutions stables permettant leur utilisation reproductible au cours du temps.Les solutions ont ensuite été imprégnées sur des échantillons textiles, par un dispositif simplifié de "padcoating"mis au point au cours de la thèse, afin de tester la fonction anti-bactérienne des textiles traités.Selon la nature des espèces imprégnées, l'optimisation des solutions conduit à une fonctionnalité antibactériennepassive ou active respectant l'aspect visuel du textile et ne dénaturant pas son toucher. Destests de lavage de laboratoire ou de lavage ménager en conditions réelles ont également montré unaccrochage notable des espèces imprégnées sur les textiles. Des options ont finalement été proposées pouraccroître cet accrochage afin de répondre à des conditions de lavage industriel. En conclusion, ce travail met en évidence le potentiel des approches d'élaboration par chimie douce en vue de fonctionnaliser des textiles, en permettant en particulier de proposer des méthodologies originales et simplifiées en adéquation avec des impératifs industriels.

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4

Gao, Weihong. "The fabrication of structurally coloured textile materials using uniform spherical silica nanoparticles." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-fabrication-of-structurally-coloured-textile-materials-using-uniform-spherical-silica-nanoparticles(c2815c09-5353-4667-a1a3-1b31b62f8787).html.

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Natural precious opals consist of silica nanoparticles of uniform diameter organised in a periodic three-dimensional structure. The physical structure of the material produces the perceived colour by a process of light diffraction. The modification of light by the physical structure of the material is also known as structural colour. This is a different process from how most surface colours are produced where light is more usually absorbed by dye and/or pigment molecules. Desirable aesthetic qualities could be achieved if the structural colours produced by natural opals could be replicated in the form of a film or a coating on textile substrates. The work presented investigates how to produce structurally coloured textiles using surface applications of uniform spherical silica nanoparticles (USSNPs). A novel one-step solvent varying (SV) technique has been developed to synthesise USSNPs with particle diameters in a controlled size range. Using suspensions containing USSNPs, structurally coloured artificial opal (AO) films have been fabricated by self-assembly using a process of natural gravity sedimentation. The sedimentation of a particular particle size range of USSNPs (from which a coloured film was produced), onto the surface of fabrics, produced a structurally coloured fabric. By controlling the mean particle diameter a wide range of spectral colours from red to blue was obtained. The light fastness properties of the coloured textiles were investigated. A further surface modification of USSNPs was performed by adding vinyl functional groups to improve the mechanical strength of the structural colour. This work suggested a novel approach to colouring textile materials without using traditional dyes and/or pigments.

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5

Quinsac, Axelle. "Effets innovants sur la soie par résonance plasmon de particules d'or." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10198/document.

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Le but de cette étude est de développer des effets innovants sur la soie par résonance plasmon. Pour cela, différents types de synthèses de nanoparticules d'or et d'alliages avec d'autres métaux nobles ont été envisagés : une synthèse préalable des nanoparticules par le biais de méthodes d'ores et déjà connues, suivie d'une incorporation sur la soie ; et une synthèse des nanoparticules in-situ sur la soie. Cette deuxième approche a permis de mettre en évidence deux effets intéressants : un effet irisé des colorations (couleur changeant en fonction de l'angle d'observation), dû à la formation simultanée sur la soie de nanoparticules plasmoniques absorbant la lumière et d'agrégats métalliques la réfléchissant ; et un effet d'addition des concentrations par rematage des pâtes d'impression permettant de réaliser des effets de superpositions et de dégradés attractifs pour les industriels. Après l'étude des paramètres de préparation, de stockage et d'impression à contrôler, la faisabilité d'un tel procédé en milieu industriel et la reproductibilité des résultats ont été validées. Il reste encore à réaliser certains réglages pour le passage à grande échelle en vue d'une future industrialisation
The purpose of this study is to develop innovative effects on silk due to plasmon resonance. For this, different synthesis pathways of pure gold nanoparticles and alloys with other noble metals have been considered: preliminary syntheses of nanoparticles through already known methods, followed by their incorporation on silk; and an in situ synthesis of nanoparticles directly on the silk. This second approach allowed us to identify two interesting effects: first, an iridescent effect of the dye (color change depending on the observation angle), due to the simultaneous formation on silk of plasmonic light-absorbing nanoparticles and light-reflective metal aggregates; second, an effect of concentrations addition by the pastes’ re-impression to achieve overlaying and gradient effects interesting for the industrial partners. After the preparation, storage and printing parameters’ study, the feasibility of such a process in industry and the reproducibility of the results have been validated. Some adjustments still need to be made in the case of a future industrialization

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6

Motay, Marvin. "Multifunctional photocatalytic substrates and textiles constructed via Layer-by-Layer self-assembly of Ag and TiO2 nanoparticles." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF030/document.

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Des films multicouches à base de nanoparticules de TiO2 et d’Ag ont été construits sur des substrats modèles et des textiles via la technique du Layer-by-Layer (LbL). Les films à base de nanoparticules de TiO2 construits sur substrats modèles ont montré un comportement photocatalytique non conventionnel pour la minéralisation de l’acide formique en phase gaz sous irradiation UV-A, et une minéralisation très importante a été obtenue avec un film possédant une unique couche de nanoparticule de TiO2. Ces films ont également montré des propriétés biocides sous irradiation UV-A. La mise en œuvre d’une méthode one-pot, combinant la synthèse photo-induite des nanoparticules d’Ag et dépôt de la couche de TiO2 par LbL, a permis la synthèse de nanoparticules d’Ag directement au sein des films et une exaltation très importante des propriétés photocatalytiques des films. Les méthodes de constructions ont été transférées avec succès sur textiles. Les films restent photocatalytiquement actifs et biocides sous irradiation UV-A après plusieurs cycles de lavages
TiO2 and Ag nanoparticle multilayered films were constructed on model substrates and textiles via Layer-by-Layer (LbL) assembly. The TiO2 nanoparticle based films constructed on model substrates showed a non-conventional photocatalytic behaviour for gas phase formic acid mineralisation upon UV-A irradiation, and a high mineralisation was obtained for a single layer TiO2 nanoparticle film. These films also showed biocidal properties upon UV-A irradiation. The elaboration of a one-pot method, combining the photo-induced synthesis of Ag nanoparticles and the LbL deposition of TiO2 nanoparticle layer, allowed the direct synthesis of Ag nanoparticles within the films and a high enhancement of the film photocatalytic properties. The construction methods were successfully transfered on textile surfaces. The films were photocatalytically active and biocidal under UV-A irradiation after several washing treatment cycles

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7

Singh, G. "Antibacterial activity testing of cotton medical textiles sonochemically impregnated with metal oxide nanoparticles." Thesis, Coventry University, 2014. http://curve.coventry.ac.uk/open/items/edeb833b-a792-49eb-bc22-bafbd374bb22/1.

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The Sonochemistry Centre at Coventry University is one of a group of organisations working on a project to develop a new technology for producing antimicrobial textiles. This technology involves the use of an ultrasonic process (sonochemical) to generate and impregnate fabrics with antibacterial metal oxide nanoparticles. The expectation is that these textiles can be produced at an affordable price for routine use in hospitals as uniforms, curtains, hospital bed sheets and linen. The aim of this PhD project was to assess the antibacterial activity of fabrics impregnated with ZnO and CuO NPs against a variety of Gram positive and Gram negative bacteria. The testing was principally carried out according to the absorption method from ISO 20743:2007. Research was also extended to compare different methods of assessing antibacterial activity of textile fabrics. These included disc diffusion tests and shake flask tests in saline or nutrient broth. Overall the results from absorption tests demonstrated that both the ZnO and CuO impregnated fabrics showed very good levels of antibacterial activity (A>2) against the test bacteria (Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa). During the optimisation of lab scale process to the pilot scale, two different types of CuO fabrics were produced to test and compare the antibacterial activity. One type of fabrics were impregnated with pre-made CuO nanoparticles by a ‘throwing the stones’ technology termed TTS and the other with sonochemically formed nanoparticles (in-situ), same as the lab process. The results indicated that the fabrics impregnated with sonochemically formed NPs displayed better antibacterial activity than the pre-made NPs. Leaching of the antibacterial agents in to saline was investigated using a shake flask method. CuO and ZnO coated fabrics prepared at laboratory scale were tested against Staphylococcus aureus, Acinetobacter baumannii and Escherichia coli. It was found that leachates prepared by shaking the fabrics in saline for 3 hours showed no antibacterial activity for CuO fabrics. However, leachates from ZnO fabrics showed an excellent activity after 24 ± 3 hours against all three bacterial species. Flow cytometry (FC) was investigated as an alternative to standard agar plate count (PC) methods for the determination of viable cell numbers. There was a general agreement between the results from agar plate counts and flow cytometry except that post incubation counts were greater with FC. The higher numbers of viable cells detected with FC may have been due to the presence of viable but not culturable cells (VBNC). Viable cells were observed by fluorescence microscopy in post incubation samples in which no viable cells were detected on nutrient agar plates. Cytotoxicity studies were conducted on ZnO and CuO fabrics from the pilot scale (both in-situ and TTS) against human dermal fibroblast cells (HDF) and human hepatocellular carcinoma cells (HepG2) using a MTT assay to determine cell viability. The results showed that ZnO and CuO are not toxic to HDF cells. However, cytotoxicity was seen in HepG2 cells with cell viability decreasing by > 14% for all the fabrics after 24 hours.

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Solomon, Meron. "Enhancing the durability of fluorocarbon-free Durable Water Repellant (DWR) formulation." Thesis, KTH, Skolan för kemivetenskap (CHE), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213517.

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The focus of the project was to alter and optimize the water repellant textile coating formulations to reach enhanced durability. For this purpose, the project was approached with three methods. Firstly, bio-based components were implemented in the mother emulsion to act as surfactant and crosslinking agent and to provide hydrophobic properties. Secondly different binders were added to crosslink and increase the coating resistance towards washes. Lastly additives at nano-scale were added to increase surface roughness in order to obtain higher hydrophobicity and improved of crosslinking capacity due to the presence of more functional groups. The stability of all emulsions was controlled using different techniques such as optical microscopy to determine particle size, distribution and any observable instability (flocculation etc.), normal aging at room temperature and accelerated aging using higher temperature. All coatings were applied using a laboratory padder on standard PA and PES pieces of textiles and hydrophobic performance was evaluated through ISO 4920 spray test. By standard washing and repeating spray test, durability could be assessed. Further structure and property studies have been run using other tests such as: contact angle measurement, breathability of the coating and SEM observations. Based on the obtained results the incorporation of low HLB, bio-based surfactants in low amount (~0,25%) resulted in an increase in the hydrophobic performance of the tested textiles. However, a decrease in shelf life could be observed with these surfactants at room temperature. Sonication was successfully used to increase both stability and shelf life significantly. Some binders and nanoparticles proved to be successful in increasing the coating quality and thus the durability. Overall many of the developed formulations could enhance performance on PA compared to the already present commercial product. On PES textile, however, the developed strategies yielded hydrophobic effect close to the commercial product.

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Vílchez, Maldonado Silvia. "Textiles funcionales obtenidos a partir de la incorporación de nanopartículas poliméricas." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/283167.

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El objetivo principal de la presente tesis es el diseño de nanopartículas de etilcelulosa para su utilización como vehículos de principios activos o sustancias lipofílicas y su deposición sobre un tejido, con la finalidad de obtener textiles funcionales. Para ello, se seleccionó como sustancia lipofílica modelo un filtro solar orgánico y como sustrato textil tejido de algodón. Debido a las características de la sustancia lipofílica seleccionada, el objetivo final de este trabajo es la obtención de tejido de algodón con propiedades protectoras frente a la radiación ultravioleta mediante la aplicación de nanopartículas poliméricas funcionales de etilcelulosa, preparadas por el método de evaporación del solvente a partir de nano-emulsiones aceite en agua (O/W). Por consiguiente, este estudio engloba el diseño de nanomateriales, su aplicación al tejido y estudio de la interacción entre las nanopartículas y el sustrato textil, y la evaluación de las propiedades finales de los tejidos tratados con nanopartículas. Las principales etapas de esta tesis son las siguientes: - Obtención de nanopartículas de etilcelulosa a partir de nano-emulsiones aceite en agua (O/W) utilizadas como plantilla o Estudio de la formación y caracterización de nano-emulsiones o Obtención de nanopartículas a partir de las nano-emulsiones seleccionadas -Aplicación de las nanopartículas sobre el tejido de algodón -Determinación de las propiedades del tejido tratado con nanopartículas Las investigaciones desarrolladas han permitido alcanzar las siguientes conclusiones principales: - Las nano-emulsiones estudiadas presentan suficiente estabilidad a 25ºC para ser utilizadas como plantilla para la obtención de nanopartículas poliméricas de etilcelulosa de tamaño <100 nm mediante el método de evaporación del solvente. - La determinación indirecta de la concentración de filtro solar en las nanopartículas por HPLC ha permitido concluir que el proceso de evaporación del solvente no induce la difusión del filtro solar hacia la fase continua del sistema, obteniendo un alto rendimiento de encapsulación (>95%). - La incorporación del agente reticulante Desmodur N100 en la fase oleosa de la nano-emulsión permite la obtención de nanopartículas insolubles en solventes orgánicos tales como etanol. Ello se ha atribuido a la reticulación de las cadenas de etilcelulosa. - La caracterización de los tejidos tratados con nanopartículas puso de manifiesto que los métodos convencionales de acabado del tejido “impregnación del tejido-paso por el foulard-secado” son adecuados para la incorporación de nanopartículas en una proporción suficiente como para otorgar funcionalidad de protección UV al tejido de algodón. - A partir de los resultados obtenidos se dedujo que en el mecanismo de anclaje de las nanopartículas en el tejido de algodón probablemente predomina la penetración de cadenas de celulosa (que se encuentran por encima de su Tg) en las cadenas poliméricas que forman las nanopartículas, formando un entrelazado que aumenta la resistencia de las nanopartículas frente a los procesos de lavado. - La evaluación de las propiedades de protección frente a la radiación UV de los tejidos tratados indica que las diversas modificaciones realizadas en el proceso de deposición de las nanopartículas sobre el tejido de algodón han permitido mejorar las propiedades de protección UV de los tejidos tratados, llegando a obtener textiles con una capacidad de protección excelente (UPF=50+). - Las medidas de transmitancia de los tejidos después de los lavados y la evaluación del detergente empleado pusieron de manifiesto que la capacidad de protección frente a la radiación UV resulta de una contribución del filtro solar de las nanopartículas que resisten después de los lavados (absorción en el intervalo UVB), y el agente blanqueante del detergente depositado en los lavados (absorción en el intervalo UVA).
The main objective of this thesis is the design of ethylcellulose nanoparticles for use as vehicles of lipophilic active substances and their deposition on fabric, to obtain functional textiles. For this purpose, it was selected as a model substance a lipophilic organic sunscreen and cotton fabric as textile. Due to the characteristics of the selected lipophilic substance, the final goal is to obtain UV protective cotton fabric. The main stages of this thesis are: - The preparation of ethylcellulose (EC) nanoparticles loaded with a sunscreen from oil in water nano-emulsions used as templates by the solvent evaporation method. - The application of EC nanoparticles on cotton fabric - The determination of the properties of the textile treated with the nanoparticles Following, the main conclusions of this work are described: - Nano-emulsions studied show sufficient stability to be used as template for the preparation of EC nanoparticles using the solvent evaporation method. - The determination of the concentration of sunscreen in nanoparticles by HPLC allow to conclude that the evaporation process of the solvent does not induce diffusion of sunscreen to the continuous phase (encapsulation efficiency > 95 % ). - The incorporation of the crosslinker Desmodur N100 in the oil phase of the nano-emulsion allows obtaining nanoparticles insoluble in organic solvents such as ethanol. - Characterization of treated fabrics showed that conventional fabric finishing methods "impregnation-padding-drying " are suitable to provide UV protection to fabric. - Evaluation of the properties of protection against UV radiation of the treated fabrics indicates that various modifications to the process of deposition of nanoparticles on the cotton fabric have improved fabric UV properties (UPF = 50+). - Results suggest that cotton textile UV protection is caused by nanoparticles (UVB absorption) and optical whitening agent deposition from detergent used in washing (UVA absorption).

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Dominguez, Kimberly. "Leaching of Silver Nanoparticles from Textiles." Ohio University Art and Sciences Honors Theses / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ouashonors155690445799457.

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11

Li, Dapeng. "Coloration of textiles with nanoparticle pigments /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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12

Schaefer, Sébastien. "Effets du dopage d'adsorbants nanoporeux par des métaux ou des semi-métaux nanodispersés sur leurs performances en stockage d'hydrogène par sorption." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0123/document.

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Dans cette thèse, des matériaux microporeux carbonés et décorés par des nanoparticules métalliques ont été synthétisés afin d’étudier l’effet de la décoration par les nanoparticules métalliques sur leurs propriétés d’adsorption d’hydrogène. L’utilisation de saccharose, de tannins de mimosa ou encore de paille de riz était en parfaite cohérence avec une démarche de respect de l’environnement et de développement durable. Le saccharose ainsi que les tannins permettent, via un prétraitement hydrothermal, d’obtenir des hydrochars qui sont ensuite activés par voie chimique ou physique. Ces synthèses ont donné accès, en fonction de paramètres de synthèse, à des matériaux à la porosité contrôlée dont les propriétés d’adsorption d’hydrogène à température ambiante ont ensuite été évaluées. En outre, l’intérêt majeur de cette thèse était de proposer un couplage entre les propriétés d’adsorption d’hydrogène, des basses pressions jusqu’à des pressions relativement élevées, et les propriétés texturales modélisées à l’aide d’outils théoriques, tels que la DFT, appliquée au fluide inhomogènes (Density Functionnal Theory). L’utilisation de dioxyde de carbone supercritique, de synthèses hydrothermales et des différents précurseurs a permis d’obtenir des matériaux dopés au nickel, au silicium ou à l’azote sans utilisation de solvant organiques préjudiciables pour la santé. Finalement, la décorrélation des différentes contributions de d’adsorption a permis de détecter et de quantifier les fractions d’hydrogène adsorbées et engagées dans divers processus tels que la physisorption, la chimisorption, le spillover et de détecter les phénomènes physisorption polarisée
In this PhD work, microporous carbonaceous materials decorated with metallic nanoparticles were developed in order to study the effect of nanodispersed metals on hydrogen sorption properties. Bio-sourced precursors such as sucrose, mimosa tannins or even rice straw have been used in order to promote eco-friendly, sustainable and innovating ways of synthesis. The use of hydrothermal pretreatment on tannins or sucrose allowed obtaining hydrochars that have been chemically or physically activated. Depending on synthesis parameters, these syntheses allowed to produce materials with controlled porosity. Then, the hydrogen adsorption properties of these materials were evaluated at ambient temperature as well as their textural properties. The main interest of this work was to propose a coupling between hydrogen sorption properties, from low to high pressure, and the textural properties. The textural properties were modelized using theoretical tools such as the DFT (Density Functionnal Theory). The use the different precursors and of decoration steps using supercritical carbon dioxide or hydrothermal synthesis, during which ones metallic or nitrogen containing precursors were used, allowed to obtain nickel, nitrogen or silicon doped materials without using harmful organic solvents. Finally, the decorrelation of the different adsorption contributions gave the possibility to detect and quantify the hydrogen fractions engaged in different processes such as physisorption, chemisorption and spillover. Polarized or enhanced physisorption was also detected using the same methods

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13

Dastjerdi, R., F. A. Sadrabadi, and S. Bahrizadeh. "Polysiloxane Sheltered Nanoparticle-Containing Intercalated Nanolayers." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35374.

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In previous researches, we have reported using cross-linkable polysiloxane (XPs) as a guideline for the design of a novel technique to stabilize different nanostructures on the textile surfaces. This followed by creating multiple-size nano-roughness on the textile surfaces using oppositely charged inorganic nanoparticles and cross-linkable polysiloxane resin to develop durable multifunctional textiles. In present study, creating multiple-size nano-roughness on the textile surfaces has been targeted via using nano-layers accompanied with nanoparticles for the textile modifications. A colloidal solution of nanoparticle-containing intercalated nanolayers has been prepared via pre-mixing of nanoparticles and nanolayers under ultrasound irradiation. Then, fabrics have been treated with the colloidal solution via the ultrasound–assistant exhaustion process. To compare the effect of combining nanoparticles and nanolayers, some samples were also produced in the absence of each component. Then, cross-linkable polysiloxane resin has been applied as a post-treatment on the nano-functionalized fabrics. The hydrophobic features of modified fabrics have been examined. According to the results, water droplet absorption time and contact angle of water droplets have been significantly increased via using the nanoparticle-containing intercalated nanolayers. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35374

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14

Momin, Nasar, and nasarhm@gmail com. "Chitosan and improved pigment ink jet printing on textiles." RMIT University. Fashion and Textiles, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20081029.154501.

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The purpose of this research was to explore two ways of the application of chitosan, a biopolymer, for ink jet printing of textiles. 1) To apply chitosan as a post-treatment on the fabric ink jet printed with pigment based inks for the fixation of pigments on the fabric. 2) To incorporate chitosan as a binder in pigment based ink jet ink formulations. The incorporation of chitosan was carried out in two ways. 1) Direct addition of chitosan into the ink formulations containing surface modified pigments. 2) Preparation of chitosan encapsulated pigment nanoparticles using complex coacervation technique and using these nanoparticles for the formulation of ink jet ink. The degree of deacetylation (DD) was determined using FTIR spectroscopy. Various protocols proposed by researchers were used to determine the DD of chitosan samples used in the present study. The protocol proposed by Raut was found to be fairly accurate in determining the DD of chitosan samples. The molecular weight of chitosan was estimated using dilute solution viscometry method. The characterisation of the film forming ability of chitosan was evaluated using scanning electron microscopy (SEM). The colour strength (K/S), colour difference, colour characteristics and colour fastness to laundering and rubbing of ink jet printed fabrics post treated with chitosan were evaluated using standard methods. Post-treatment (pad-dry-cure method) of cotton fabric ink jet printed with pigment based inks revealed that chitosan could effectively fix the pigments on cotton compared to the commercial textile binders and the water-soluble derivative of chitosan. The chemical interaction between chitosan and cotton fabric was illustrated by FTIR-ATR analysis and through determination of carboxyl group content. The ink jet printed cotton fabric post treated with 3gpl chitosan (MW 156,156) maintained almost 86% of bacterial reduction against Klebsiella Pneumoniae even after 50 launderings. Inks containing chitosan were formulated and were found to be stable in terms of mean particle size and viscosity over a period of one month and for 4 freeze/thaw cycles. A magenta ink containing chitosan was selected for ink jet printing of cotton fabric. It was found that the DF was around 97% for magenta ink containing chitosan compared to around 53% fixation for magenta ink without chitosan on cotton fabric. Surface modified carbon black pigment with carboxylated (COO-) surface functionality was selected to prepare chitosan encapsulated pigment nanoparticles by complex coacervation technique. Chitosan encapsulated pigment nanoparticles with mean particle size diameter of 876 nm and 742 nm were formed when 5 ml of 0.1% w/v pigment was mixed with 2ml and 3ml of 0.1% w/v chitosan, respectively. However, no correlation was found between the particle size of the nanoparticles formed and the concentration of chitosan. The DF with ink containing chitosan encapsulated pigment nanoparticles was found to be around 98% while the blank ink with only surface modified carbon black pigment showed 44% fixation.

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15

Hardian, Rifan. "Interplay between structure, texture, and reactivity in MOFs in the case of amorphous, defective, and composite materials." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0419/document.

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Metal-Organic Frameworks (MOFs) sont constitués de clusters métalliques connectés dans les ligands organiques. L'objectif principal de ma thèse était de caractériser la texture, la structure et la réactivité des MOFs dans le cas de systèmes présentant des défauts, amorphes et composites.La première étude est centrée sur les propriétés de la famille Fe-BTC et ce travail a été réalisé en collaboration avec l'Université d'Utrecht et l'Université d'Oxford. Une étude comparative entre le MIL-100(Fe) et son homologue commercial Basolite F300 (BASF) qui est amorphe ont été évaluées par l’adsorption de méthanol et d'autres techniques de caractérisation. De plus, les deux matériaux ont été testés pour être utilisés comme support pour l'imprégnation des métaux.Dans la deuxième étude, le broyage à la bille est utilisé comme stratégie de modification post-synthèse de MOFs. Le matériau ZIF-8 a été sélectionné de cas car il s'agit d'un MOF disponible dans le commerce (Basolite Z1200) et qui est en train de devenir de référence dans ce domaine. Ce chapitre examiner des propriétés flexibles, de la texture, de la structure, et la réactivité.Les MOFs UiO-66 et MOF-808 sont également analysées. Ces études ont été réalisées en collaboration avec l'Université Technique de Munich. UiO-66 contenant différents défauts d'ingénierie sont examinées. Nous avons démontré que les mesures d’adsorption de vapeur peuvent être un outil précieux pour accéder à la chimie des défauts. Le deuxième système est la série MOF-808 qu’une étude complète est présentée allant des diverses stratégies de synthèse de MOFs défectueux et composites jusqu'à leur propriété d'adsorption et de réactivité
Metal-organic frameworks (MOFs) are a class of porous materials that constructed from metal clusters connected with organic linkers. The main objective of my PhD was to characterize the texture, structure, and reactivity of MOFs materials with a particular focus on defective, amorphous and composite materials. The first study is centered on the properties of the Fe-BTC family and this work was realized in collaboration with Utrecht University and the University of Oxford. A comparative study between crystalline MIL-100(Fe) and its commercial counterpart amorphous Basolite F300 (BASF) were studied by using methanol adsorption to predict the reactivity. Other characterization methods are introduced to investigate both materials which were further tested to be used as supports for metal-impregnation. In the next study, ball-milling was employed as a post-synthesis strategy for MOF modification. This ZIF-8 material was selected since it is commercially available (Basolite Z1200) and is becoming one of the reference materials in this area. Extensive studies including flexibility, textural, structural, as well as reactivity of different milling products is presented. Zirconium-based MOFs (UiO-66 and MOF-808) were also examined in this thesis. These studies were performed in collaboration with TU Munich. UiO-66 series containing engineered defects are first examined. We demonstrated that vapor adsorption measurement is a valuable tool to access the chemistry of the defects. The second studied system is MOF-808 series, where a comprehensive study is presented starting from synthesis strategies of defective and composite MOFs up to adsorption properties and reactivity

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16

Dan, Chengyi. "Effects of nanoparticles on the microstructure and crystallographic texture evolution of two Aluminium-based alloys." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS147.

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Les effets des nanoparticules (cisaillables et non-cisaillables) sur l’évolution microstructurale et l'évolution de la texture cristallographique des deux alliages à base d’aluminium après laminage à froid ont été étudiés dans cette thèse. Un alliage Al-Sc contenant des nanoparticules cisaillables de Al3Sc et un composite Al-TiB2 contenant des nanoparticules non-cisaillables TiB2 sont étudiés. La microscopie électronique en transmission (MET), la diffraction d'électrons rétrodiffusés (EBSD) et l’analyse de la texture par la diffraction de neutrons sont utilisées pour caractériser le développement de la microstructure et la texture cristallographique lors du laminage à froid des 2 alliages.La restauration dynamique pendant laminage a été inhibée dans la matrice contenant des Al3Sc nanoparticules cisaillables et TiB2 non-cisaillables. Par conséquent, peu de cellules de dislocation ont été générées dans la matrice, ce qui limite la diminution de la taille des grains.Le développement de la texture de laminage est retardé par les nanoparticules cisaillables ou les particules non-cisaillables. Des bandes d’orientation de cube résiduelles se trouvent dans les matériaux contenant des particules cisaillables dans une matrice très déformée en raison de la limitation du glissement croisé. La réduction de la proption volumique des composantes de texture du laminage se produit dans les matériaux contenant de grandes particules non-cisaillables (de l’ordre d’un micromètre) en raison de la recristallisation dans les PDZs (Particle Deformation Zones), ce qui contribue également à la diminution des grains.De plus, le cisaillement de nanoparticules favorise le glissades en plan, ce qui conduit à une forte localisation des déformations et à l'apparition de bandes de cisaillement. La génération de bandes de cisaillement dépend de l'orientation et est dû au changement soudain des chemins de déformation et et de l'inhibition de la récupération dynamique. Les nanoparticules non cisaillables ont probablement pivoté avec la matrice environnante, ce qui pourrait constituer un nouveau mécanisme de déformation
The effects of shearable and non-shearable nanoparticles on the microstructure and crystallographic texture evolution of two Al-based alloys after cold rolling have been studied in this thesis. An Al-Sc alloy containing shearable Al3Sc nanoprecipitates and Al-TiB2 composite containing non-shearable TiB2 nanoparticles are investigated, respectively. Transmission electron microscopy (TEM), electron backscatter diffraction (EBSD) and neutron diffraction texture analysis are employed to characterize the microstructure and texture development of the two alloys during cold rolling.Dynamic recovery has been inhibited in the matrix containing both shearable (Al3Sc) and non-shearable (TiB2) nanoparticles due to the pinning effects. Hence, few dislocation cells are generated in these matrices that impedes the grain refinement.The development of rolling texture is retarded by either shearable nanoprecipitates or non-shearbale particles. Obvious residual Cube orientation bands are found in materials containing shearable precipitates at the deformed states due to the limitation of cross-slip. Volume reduction of rolling texture components occurs in materials containing large non-shearable particles (about 1 micrometer) due to the recrystallization at PDZs (Particle Deformation Zones), which contributes to grain refinement.In addition, the shearing of nanoprecipitates promotes planar slip leading to strong strain localization and the occurrence of shearbands. The generation of shearbands is orientation dependent and results from the sudden change of deformation paths and inhibition of dynamic recovery. The non-shearable nanoparticles probably have rotated together with the surrounding matrix, which could be a new deformation mechanism

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17

Lillie, John. "Mesoporous silica nanoparticle incorporation of essential oils onto synthetic textiles for tailored antimicrobial activity." Thesis, Manchester Metropolitan University, 2016. http://e-space.mmu.ac.uk/608777/.

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Healthcare associated infections (HCAI) impose significant financial and environmental problems for modern healthcare settings, therefore it is important to develop novel strategies to combat HCAIs and the causative microorganisms. This study investigates the use of an encapsulated essential oil (EO) antimicrobial coating for textiles in the healthcare environment. The antimicrobial activity of several EOs were studied, individually and in blends, against five microorganisms associated with HCAI (Staphylococcus aureus, methicillin resistant Staphylococcus aureus, Candida albicans, Escherichia coli, and Pseudomonas aeruginosa). A 1:1 blend of cinnamon (CIN) and clove oils (CLO) containing 94.8 % (v/v) eugenol (by GC-MS) showed the highest antimicrobial efficacy and gave a minimum inhibitory concentration (MIC) of less than 0.25% (v/v). Mesoporous silica nanoparticles (MSN) were used to encapsulate volatile EOs. The MSNs displayed narrow size distribution, high surface area and pore size between 1.8-2.2 nm. MSNs, directly loaded with CIN:CLO blend (72 % by mass of MSN), achieved bactericidal values (25-50 mg/mL) against the test microorganisms. Dynamic killing profiles of the EO loaded MSNs against the test microorganisms were recorded. The highest kill rates were observed during the first 15 minutes of contact. Organically modified silica (ormosil) gels were synthesised to provide thin film coverage of synthetic fibres. Gamma-methacryloxypropyltrimethoxysilane (-MPS) was used to attach un-loaded MSNs to the ormosil coating. A layer-by-layer treatment method provided good coverage of synthetic fibres with MSNs, as evidenced by scanning electron microscopy (SEM). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used to monitor the layer-by-layer treatment sequence. Head space GC-MS sampling of EO loaded MSN treated textile coupons showed that EO was able to diffuse from the MSN mesopores after being bonded to the synthetic fibres. The EO loaded MSN textile coupons were microbiologically challenged using a method based on AATCC 100. The EO loaded MSN textile coupons displayed good antimicrobial activity over five washing cycles using a method based on (AATCC 61 and 135) thereby indicating a degree of controlled release.

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Mmelesi, Olga Kelebogile. "Synthesis and characterization of pine cone carbon supported iron oxide catalyst for dye and phenol degradation." Thesis, Vaal University of Technology, 2017. http://hdl.handle.net/10352/418.

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M. Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology
Fenton oxidation is classified into two processes, homogeneous and heterogeneous. Homogeneous Fenton oxidation process, have been shown to be efficient in the degradation of organic pollutants. However, it was shown to have limitations which can be addressed by the heterogeneous Fenton oxidation. Despite the high efficiency of the heterogeneous Fenton oxidation process in the degradation of recalcitrant organic pollutants, the currents synthesis trends of the heterogeneous Fenton catalyst have been proven to be time and energy constraining, since it involves the multi-step were the activated carbon have to be prepared first then co-precipitate the iron oxide on the activated carbon. However, as much as the heterogeneous Fenton catalyst has been proven to have high catalytic activity towards degradation of organic pollutants, these catalysts have some limitations, such limitations include metal ions being leached from the catalyst support into the treated water causing catalyst deactivation and a secondary pollution to the treated water. In this thesis, these catalysts have been applied in the degradation of recalcitrant organic pollutants such as methylene blue and phenols. This study focuses on the single step synthesis of iron oxide nanoparticles supported on activated carbon, were carbonaceous material is impregnated with iron salt then pyrolysed via microwave heating. Microwave power and the amount of iron salt were optimized. The prepared activated carbon-iron oxide composites were applied to the degradation of 2-nitrophenol (2-NP) and methylene blue (MB). Methylene blue was used as a model compound due to the fact that it is easier to monitor the degradation process with UV-Vis as compared to 2-nitrophenol . 2-nitrophenol the additional step for the adjustment of pH is required since nitrophenols are colorless in color at lower pH. The characterization showed that the microwave power and the amount of the iron precursor have an influence on the porosity and surface functional groups of the activated carbon. Further it was vi observed that microwave power and iron precursor influnces the amount of iron oxide formed on the surface of the support. It was also observed that the activated carbon-iron oxide composite have the catalytic effects on the Fenton oxidation process of MB and 2-NP. The parameters such as H2O2, pH, catalyst dose, initial concentration, temperature affect the degradation of both MB and 2-NP. Kinetics studies showed that Fenton is a surface driven reaction since the results fitted the pseudo first order model. The thermodynamics parameters also showed that the reaction is endothermic, spontaneous and is randomized. This implies that the reaction of the degradation of MB and 2-NP is feasible and the catalysts prepared have high catalytic activity. MB and 2-NP were degraded to smaller organic molecules (carboxylic acids). The stability of the catalyst observed to decrease as the number of cycles increased, this is due to the leaching of iron ions from the support material. Hence it was concluded that the activated carbon-iron oxide composite was successfully synthesized and had the high catalytic activity for the degradation of MB and 2-NP.

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19

Twardoch, Marek. "Layer-by-layer modification of textiles : development of self-decontaminating functionalized textiles." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAE008.

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Les surfaces photo catalytiques permettent la fabrication de matériaux auto-décontaminants. Des textiles de ce type fonctionnant à la lumière naturelle peuvent grandement améliorer le niveau d’hygiène dans les pays en développent. L’assemblage couche par couche est bien adapté à la fonctionnalisation de textiles, cette technique permet de construire des revêtements composites hybrides avec un control nanométrique de la composition et de l’architecture, et cela indépendamment de la nature ou de la géométrie de la surface. Ce travail décrit la fabrication de revêtements photo-catalytiques composés de nanoparticules de TiO2 et de polyélectrolytes pour des applications d’auto-décontamination. Nous avons montré qu’il était possible de fabriquer des revêtements poreux et homogènes dont le contenu en photo-catalyseur est ajustable en fonction du nombre de couches et des paramètres de dépôts. Les textiles obtenus montrent des résultats prometteurs pour la dégradation de colorants et de polluants gazeux. La spectroscopie EPR nous a aussi permis d’investiguer les mécanismes de formation et la réactivité des radicaux sous illumination
Photocatalysis can be efficiently utilized for obtaining self-decontaminating properties of different surfaces. Production of sun driven self-decontaminating textiles can highly improve level of hygiene, especially in undeveloped countries. To prepare coatings on textiles, the Layer-by-Layer assembly method seems to be very attractive as it allows to build multifunctional hybrid materials with controlled nanoscale composition and architecture, regardless of surface type and geometry. This work describes the preparation of photocatalytically active coatings composed of TiO2 nanoparticles and polyelectrolytes for self-decontaminating applications. The quantity of deposited catalysts within the films can be precisely controlled by adjusting the number of layers and the deposition parameters. Coated textiles showed promising results in degradation of dyes and gas pollutants. In order to better understand degradation mechanisms, radical production in films during illumination have been investigated by EPR spectroscopy

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20

Le, Hoai Nga [Verfasser], Gianaurelio [Gutachter] Cuniberti, Michael [Gutachter] Stintz, and Sven [Gutachter] Wießner. "A concept for nanoparticle-based photocatalytic treatment of wastewater from textile industry / Hoai Nga Le ; Gutachter: Gianaurelio Cuniberti, Michael Stintz, Sven Wießner." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://d-nb.info/1226430562/34.

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21

Binotto, Ghislain. "Poudres d’oxydes de métaux de transition à texture, morphologie et taille contrôlées : de l’électrochimie à la catalyse." Amiens, 2008. http://www.theses.fr/2008AMIE0127.

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L’engouement croissant pour les applications portables et automobiles place les batteries Li-ion au premier rang pour le stockage électrochimique de l’énergie. L’intérêt récent pour les matériaux d’électrode nanométriques nous a conduit à l’étude de l’oxyde de cobalt Co3O4 stœchiométrique précipité en solution aqueuse (Co3O4-P). Il est constitué de particules nanométriques cristallisées (40 Å) regroupées en agglomérats micrométriques développant une porosité très finement distribuée. L’étude structurale a révélé une délocalisation partielle des cations en sites 16c et 48f, d’autant plus importante que la taille des domaines est faible. La préservation de la texture, donc les meilleures performances électrochimiques, sont obtenues pour un mélange oxyde/carbone par suspension dans un solvant organique. Une capacité de plus de 600 mAh/g est ainsi maintenue sur vingt cycles. La capacité irréversible au premier cycle est similaire à celle des matériaux massifs, suggérant que leur étape de formatage n’est pas responsable de cette irréversibilité, en partie attribuable à la formation de la phase -CoO. La chute de capacité est principalement attribuée à la dissolution de la matière active dans l’électrolyte ainsi qu’aux effets de la décomposition irréversible du solvant. Différents tests cinétiques de décomposition (NH3, toluène, H2O2, CO) montrent la forte activité catalytique de Co3O4-P. Des résultats préliminaires très encourageants quant aux propriétés catalytiques de Co3O4-P (et dérivés) en cellules Li/O2, en particulier au niveau de la polarisation de la batterie, font de ce matériau un outil idéal pour mettre en relation les domaines de l’électrochimie et de la catalyse
The Li-ion battery technology is so far the best candidate to match the growing demand for portable and automotive power sources. The recent focus on nanomteric electrode materials for Li-ion cells leads us to consider Co3O4 precipitated in aqueous solution (Co3O4-P). This material is made of crystallized nanometric particles (40 Å), forming porous micrometric agglomerates exhibiting a very narrow porosity distribution. A structural investigation shows a partial cationic delocalization in 16c and 48f sites, in an extent inversely proportional to the size of the coherent domains. The powder texture is maintained, and therefore the optimum electrochemical performances, are obtained through the oxide/carbon mixing in suspension in a solvent. A capacity of more than 600 mAh/g is reached along twenty cycles. The first cycle irreversible capacity is equivalent to that of micrometric materials, suggesting that the formatting step is not responsible for this irreversibility, partially attributed to the formation of -CoO. The drop in capacity along cycling is mostly due to the dissolution of the active material in the electrolyte, and to the effects of the irreversible decomposition of the solvent. Different kinetic decomposition tests (NH3, toluene, H2O2, CO) demonstrated the catalytic efficiency of Co3O4-P. Preliminary catalytic and electrochemical results for Co3O4-P and post-annealed materials as catalysts in Li/O2 batteries, mainly regarding the lowering of the cell polarization, let us consider this set of materials as an ideal tool for bridging the electrochemistry and catalysis domains

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22

Massella, Daniele. "Preparation of biofunctional textiles by surface functionalization based on the nanoencapsulation technique." Thesis, Lille, 2020. http://www.theses.fr/2020LILUI077.

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La présente thèse a été réalisée dans le cadre du projet de doctorat joint SMD-Tex, en partenariat entre le POLITO (Italie), l’ENSAIT (France) et à l'Université de Soochow (Chine). Le but de ce travail est de proposer de nouvelles approches pour la production de textiles biofonctionnels. Ces produits sont constitués de textiles qui ont subi des traitements de finition spéciaux pour conférer des propriétés qui présentent des effets bénéfiques pour la santé de l'utilisateur.Longtemps la recherche pharmaceutique a étudié des outils nouveaux et plus efficaces pour administrer un médicament au patient. Le but de ces études est d’admiistrer des dosages thérapeutiques efficaces sur une longue période, en minimisant le nombre d'administrations requises et les effets secondaires possibles. Dans ce contexte, la peau a été considérée comme une voie de libération de médicaments locaux et systémiques. Une telle approche est plus simple et moins invasive que d'autres voies. Donc, plusieurs stratégies ont été développées pour délivrer efficacement des médicaments à travers la barrière cutanée. Parmi celles-ci, la technologie d'encapsulation permet l'incorporation des substances actives à l'intérieur des nanoparticules (NP) pour i) protéger le médicament, ii) le délivrer efficacement à travers la peau iii) contrôler la libération au fil du temps.Dans le présent travail, des NP chargés de médicament ont été produits en utilisant de la polycaprolactone (PCL) comme membrane. Les nanoparticules produites ont ensuite été utilisées pour le finissage des tissus en coton produisant des textiles biofonctionnels destinés à être utilisés comme dispositifs portables de distribution de médicaments. La technique de nanoprécipitation flash (FNP) a été exploitée pour la production des NPs en raison de sa productivitè, et simplicité. La pertinence du procédé FNP pour produire des NP destinés à être utilisés dans la préparation de textiles biofonctionnels a été étudiée. Les nanoparticules PCL ont été produites en chargeant trois médicaments différents dans le système, à savoir la caféine, la mélatonine et la curcumine. Ces médicaments sont en effet considérés comme des médicaments modèles en termes de niveau d'hydrophilie. Ce dernier est une propriété clé dans la détermination du résultat du processus d'encapsulation et de la perméation cutanée.Le procédé FNP a été exécuté en dissolvant le polymère dans un solvant organique et en faisant entrer le courant de solution en collision avec un courant d'antisolvant dans un micromélangeur, entraînant la précipitation du polymère sous forme de nanoparticules. Pour chaque substance active, les protocoles expérimentaux et les méthodes analytiques ont été ajustés pour mieux étudier le système de NP chargé de médicament. L'effet de la formulation ainsi que les paramètres du procédé sur les taille et la capacité d’enrobement des nanoparticules ont été étudiés. De plus, les formulations de NP ont été caractérisées pour obtenir des informations sur leurs propriétés physiques et chimiques par diverses techniques. Les particules ont été appliquées au textile de coton soit par des méthodes d'imbibition ou d'imprégnation. L'efficacité du traitement de fonctionnalisation a été évaluée en combinant différentes analyses. Les propriétés biofonctionnelles ont été étudiées en termes d'activité antioxydante, de facteurs de protection UV et de libération de médicaments. Pour ce dernier test, la méthode des cellules de Franz a été employée. L'étude a montré que le FNP permet de produire des NPs de PCL chargées de médicament pour les trois substances étudiées. Le traitement de finition proposé a permis de fonctionnaliser efficacement la surface du tissu. Les textiles traités ont permis de délivrer efficacement les principes actifs à la peau avec des profils de perméation dépendant des propriétés du médicament. La finition des nanoparticules confère également au coton des propriétés antioxydantes et de protection contre les UV
This study was performed in the frame of the SMD-Tex Joint Doctorate project. The doctoral research activities were carried out in three mobility periods at POLITO (Italy), Ensait (France), and University of Soochow (China). This work aims to propose novel approaches for the production of biofunctional textiles. These products consist of textile fabrics which underwent special finishing treatments to confer properties that display beneficial effects to the user's health.In the last decades, pharmaceutical research has been investigating novel and more effective tools to administer a drug to the patient. The scope of these studies is to provide effective therapeutic dosages over a long time, minimizing the number of required administrations and the possible side effects. In this context, the skin has been regarded as a potential route for the release of local and systemic drugs. Such an approach is simpler and less invasive compared to other routes. Therefore, several strategies have been developed to effectively deliver drugs across the skin barrier. Among them encapsulation technology allows the incorporation of the active substances inside nanoparticles (NPs) to i) protect the drug, ii) effectively deliver it through the skin iii) control the release over time.In the present work, drug-loaded NPs were produced by employing polycaprolactone (PCL) as shell material. The produced nanoparticles were then used to finish cotton fabrics producing biofunctional textiles to be employed as wearable drug delivery devices. The flash nanoprecipitation technique (FNP) was exploited for the nanocarrier production being identified as a simple, sustainable and efficient production process. The suitability of the FNP process to produce NPs to be used in the preparation of biofunctional textiles was investigated. The PCL nanoparticles were produced by loading three different drugs in the system i.e. caffeine, melatonin, and curcumin. Such drugs are indeed considered model drugs in terms of hydrophilicity level. The latter is a key property in determining the outcome of the encapsulation process and the dermal permeation.The FNP process was run by dissolving the polymer in an organic solvent and making the solution stream collide against an antisolvent stream in a micromixer, resulting in the polymer precipitation in the form of nanoparticles. The drugs were precipitated together with the polymer upon being added either to the solvent or the antisolvent stream. For each active substance, the experimental protocols and analytical methods were adjusted to better investigated the drug-loaded NPs system. The effect of the formulation as well as the process parameters on the properties of the nanoparticles was investigated. The process was optimized to produce particles with a diameter lower than the one of skin pores. The amount of drug loaded in particles was investigated by loading capacity (LC) and encapsulation efficiency (EE). Furtherly, the NP formulations were characterized to obtain insights on their physical, chemical, and morphological properties by various analytical techniques.The particles were applied to the cotton fabric either by imbibition or impregnation methods. The effectiveness of the functionalization treatment was evaluated combining different analyses. The biofunctional properties were studied in terms of antioxidant activity, UV protection factors, and drug release. For the latter test, the Franz cell method was employed using either artificial and excised porcine skin membranes.The study showed that the FNP allows producing drug loaded PCL NPs for all the three investigated substances. The proposed finishing treatment allowed to effectively functionalize the fabric surface. The treated textiles allowed to effectively deliver the active principles to the skin with permeation profiles dependent on the drug properties. The nanoparticle finishing also imparted cotton antioxidant and UV protection properties

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23

Rault, François. "Mise en oeuvre et propriétés mécaniques, thermiques et de tenue au feu de filaments à base de polypropylène chargé en nanoparticules." Valenciennes, 2008. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/fdf2aa0d-1453-4fee-8b94-d1e493d57372.

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Le textile français est une industrie très concurrencée où les différents acteurs cherchent à se démarquer en améliorant ou en apportant de nouvelles propriétés à leurs produits. Le coût restant une préoccupation majeure, le PP, polymère présentant un compromis coût / propriété intéressant, est donc largement utilisé. Différentes voies existent alors pour le fonctionnaliser. L’une d’elle consiste à lui adjoindre des charges. Toutefois, la taille et le taux de particules communément ajoutés pour atteindre des propriétés satisfaisantes provoquent des difficultés de mise en œuvre lors de l’étape de filage en voie fondue. De par leurs caractéristiques (taille et quantité nécessaire), les nanoparticules offrent une alternative intéressante à explorer. Des mélanges PP / Argile ont été préparés avec une extrudeuse bi-vis avant d’être filés. Une forte diminution des propriétés d’allongement des filaments en présence d’argile, imputable sans doute à sa faible délamination, nous à amener à envisager la réalisation de mélanges ternaires (PP / PA6 / Argile). La morphologie spécifique de tels mélanges a toutefois rendu impossible leur mise en œuvre sous forme de filaments pour un taux de charge supérieur à 1%. Des filaments de PP chargé en argile et en graphite ainsi que des filaments de PP chargé en nanoparticules à base de manganèse ont également été produits pour évaluer leurs propriétés thermiques et mécaniques. Toutes les nanocharges testées ont entraîné une amélioration de la stabilité thermique du PP sous air. Pour finir, les filaments réalisés ont été utilisés pour produire des étoffes maillées, dont les propriétés feu ont été étudiées à l’aide d’un calorimètre à cône
The french textile industry meets stiff competition. The firms try to differentiate themselves by improving or adding new properties to their products. The cost remaining a major concern, PP, polymer with an interesting compromise cost / ownership, is therefore widely used. Different ways exist to functionalize this polymer. One of them is to add fillers. However, the size and rate of particles commonly added to achieve satisfactory properties cause difficulties during the melt spinning process. Due to their characteristics (size and filler rate), nanoparticles offer an interesting alternative to explore. Blends PP / Clay were prepared with a twin-screw extruder before being spun. A strong decrease in the elongation properties of filaments in the presence of clay, probably due to its low exfoliation, brings us to consider the preparation of ternary blends (PP / PA-6 / Clay). However, it was not possible to spin these blends for a filler rate higher than 1 wt% due to their specific morphologies. Filaments of PP filled with clay and graphite and filaments of PP filled with based manganese nanoparticles have also been produced to assess their mechanical and thermal properties. Under air, thermal stability of PP has been improved with all tested fillers. And finally, the filaments made were used to produce knitted fabrics, whose fire properties have been studied with a cone calorimeter

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Mendoza, Luz Esmeralda Roman. "Funcionalização de tecidos têxteis com nanopartículas para proteção UV." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/100/100133/tde-14062018-161627/.

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Nos últimos anos no Brasil, instituições como o Instituto Nacional de Câncer José Alencar Gomes da Silva e o Ministério da Saúde, reportaram o aumento de casos de câncer de pele. O câncer de pele é uma das doenças mais comuns a nível mundial e pode estar relacionado à exposição à radiação ultravioleta (UV). O objetivo do presente trabalho foi realizar a funcionalização de tecidos sarja 100% algodão com nanopartículas (NPs) de óxido de zinco (ZnO), as quais possuem propriedades para aplicação como protetor solar, melhorando desta forma as características de proteção à radiação UV do algodão. As NPs de ZnO foram sintetizadas pelo processo de precipitação, empregando nitrato de zinco hexahidratado (Zn(NO3)2.6H2O) e hidróxido de sódio (NaOH). A síntese in situ das NPs de ZnO sobre os tecidos foi realizada por meio do processo de esgotamento, usando o equipamento de tingimento têxtil HT (High Temperature). Para este processo foram utilizadas diferentes concentrações de Zn(NO3)2.6H2O (2, 5, 8 e 10% sobre a massa do tecido) e NaOH (0,7; 1,6; 2,5 e 3,0 g/L), respectivamente. A avaliação do fator de proteção UV (FPU) e os testes de resistência à lavagem dos tecidos foram realizados segundo normas as AATCC 183:2004 e AATCC 61:1996, respectivamente. Foram promovidas também aplicações de resinas têxteis comerciais sobre os tecidos funcionalizados e determinação das propriedades físicas. Além disso, foram realizadas caracterizações de vibração molecular, estruturais e morfológicas das NPs de ZnO e para os tecidos funcionalizados foram efetuadas caracterizações estruturais, morfológicas e térmicas. Os resultados mostraram que tanto as NPs de ZnO como as sintetizadas in situ sobre os tecidos apresentaram estrutura cristalina hexagonal wurtzite. As NPs de ZnO mostraram uma morfologia de estrela com pontas muito protuberantes enquanto que as NPs sintetizadas no tecido apresentaram morfologia similar, mas com pontas pequenas. Para todas as concentrações de nitrato de zinco estudadas, antes e após as 20 lavagens, o FPU dos tecidos funcionalizados com NPs de ZnO tiveram categoria de proteção UV entre boa e excelente
In Brazil, institutions such as the José Alencar Gomes da Silva National Cancer Institute (INCA) and the Brazilian Ministry of Health reported increase and appearance of new types of cancer in recent years. Skin cancer is the most common type of disease worldwide and generally might be related to the exposure of the skin to ultraviolet (UV) radiation generated by the sun. The objective of this work was to perform the functionalization of 100% cotton woven fabrics with zinc oxide (ZnO) nanoparticles (NPs), which has interesting properties for applications as solar protector, thus improving the protection characteristics of cotton against UV radiation. ZnO NPs were synthesized by the precipitation process using zinc nitrate hexahydrate (Zn(NO3)2.6H2O) and sodium hydroxide (NaOH). In situ synthesis of ZnO NPs onto the fabric was carried out via exhaust dyeing method, using the textile High Temperature (HT) dyeing machine. For this process, different concentrations of Zn(NO3)2.6H2O (2, 5, 8 and 10% on the weight of fabric) and NaOH (0.7, 1.6, 2.5 and 3.0 g/L) were used. The evaluation of UV protection factor (UPF) and wash durability tests were performed according to AATCC 183:2004 and AATCC 61:1996 standards, respectively. Commercial textile resins applications onto functionalized fabrics and determination of physical properties were also performed. In addition, molecular, structural and morphological characterizations of ZnO NPs were carried out and structural, morphological and thermal analyzes were performed for functionalized fabric. The results showed that both ZnO NPs and those in situ synthesized onto the fabric, exhibited wurtzite hexagonal crystalline structure. The ZnO NPs displayed a star-like morphology with very pronounce tips, while the NPs onto the fabric had a similar morphology but with small tips. For all concentrations of zinc nitrate studied, before and after 20 cycles washing, the UPF of cotton fabrics functionalized with ZnO NPs had an UV-protection category between good to excellent

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Guillot, Murielle. "Elaboration et caractérisations de matériaux lamellaires hybrides inorganiques-organiques dérivés des Phyllosilicates : Précurseurs de nanoparticules de nickel métallique." Université Louis Pasteur (Strasbourg) (1971-2008), 2002. http://www.theses.fr/2002STR13053.

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Ce travail s'interesse a l'elaboration et a la caracterisation de nouveaux materiaux hybrides lamellaires inorganiques-organiques derives des phyllosilicates. L'introduction bibliographique rappelle d'abord la structure de phyllosilicates et rend compte de la modification apportee a cette structure lorsque les tetraedres sio4 sont remplaces par des tetraedres h2n(ch2)3-sio3. Une analyse critique des resultats de la litterature vise a proposer non seulement un procede d'optimisation (role du ph, de l'agent mineralisant, du rapport molaire ni/si, de la dilution , voie hydrothermale) de la cristallinite, mais egalement une caracterisation structurale detaillee de ces composes, dont le caractere nanometrique ne permet pas d'affiner un modele structural. Malgre l'empilement aisement identifiable de feuillets ni(oh)2, de type brucite, l'organisation des especes dans l'espace interfoliaire (21 Å), est difficile a determiner. Un effort important a ete consacre a l'etude par exafs de l'environnement local autour du nickel afin de montrer que les atomes de silicium sont bien presents dans la sphere de coordination du nickel, mais egalement de determiner leur position relative par rapport a ce dernier. L'exafs-polarise, applique a des films textures, a montre que les especes silicates ont un degre d'organisation a la surface des feuillets brucite moindre que celui des phyllosilicates. D'autre part, ces materiaux hybrides presentent un ordre magnetique a basse temperature et permettent d'ancrer des molecules organiques dans l'espace interfoliaire. Ces resultats ouvrent ainsi la voie a un travail visant a mettre au point des dispositifs associant plusieurs proprietes physiques. Dans un registre different, une etude a montre que ces materiaux hybrides sont des precurseurs potentiels de nanoparticules de nickel metallique par generation in-situ d'especes reductrices des 200ʿc sous argon

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Yan, Xiang. "Design of biphasic polymeric fiber from melt-spinning charged with nanoparticles : effects of the formulation and the fillers localization, to obtain a functionalized fiber at surface level." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I084.

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Le but de ce travail est de développer des filaments fonctionnels de polypropylène (PP) poreuses mais aussi des microfibres de PP par filage voie fondu de mélange de polymères immiscibles PP/Poly(vinyl-alcool) (PVA) après extraction sélective de la phase de PVA. Le premier objectif est de déterminer le ratio optimal entre le PP et le PVA afin d’obtenir la filabilité du mélange et de localiser les charges à l’interface du mélange biphasique. Les charges utilisées sont à la fois des nanoparticules de silices modifiées ainsi que des particules Janus à base de kaolinite, favorisant la localisation à l’interface. Les morphologies et les localisations des charges ont été analysées à la fois sur des joncs extrudés ainsi que sur des fibres. Le travail s’est concentré principalement sur des ratios de polymères permettant d’obtenir des fibres de PP poreuses, mais un travail exploratoire a permis de déterminer les conditions d’obtention de microfibres de PP. Le ratio PP/PVA avec 70 % de PP et 30 % de PVA en masse est la formulation idéale pour fabriquer ces fibres poreuses. La localisation des nanocharges de silice dans le mélange biphasique est principalement contrôlée par la thermodynamique du mélange, et en fonction des tensions de surface des nanosilices, la localisation à l’interface a pu être obtenue. De plus, les particules Janus permettent une voie alternative afin d’obtenir une localisation à l’interface, qui apportent un renforcement mécanique de la formulation. La faisabilité de la production de microfibres via l’inversion de phase PVA/PP avec l’ajout de nanocharges a été démontrée
The work aims to make the functional porous polypropylene (PP) fibers as well as PP microfibers, by the melt spinning of PP-poly(vinyl alcohol) (PVA) blends followed with the selective phase extraction of PVA. The objective is to first find out the optimal ratio of PP and PVA for fabrication of multifilament yarns by melt spinning, and to localize the filler at the biphasic interface. The fillers include not only the homogenously modified silica nanoparticles, but also the kaolinite Janus particles. The concomitant morphology evolution of the extrudates and fibers were observed. The work mainly discusses about the fabrication of porous fibers, but also makes an exploratory experiment to reverse the ratio to fabricate the microfibers. It was found that the ratio of two polymers as 70 wt.%/30 wt.% is an ideal formula for fabricating the porous fibers. Both of the two fillers are successfully tailored at the biphasic interface. The localization of silica nanoparticles within the biphasic can be fixed by the thermodynamic control, and one of the sorts has been dominantly localized at the biphasic interface. In addition, the Janus particles provide an alternative way to have the interface localization, which even helps the mechanical enhancement. The feasibility of microfiber production with the embedment of the fillers was also demonstrated

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Benoit, Virginie. "Relation entre structure et texture de matériaux poreux et l'évaluation de leurs propriétés de piégeage du CO2." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0635/document.

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Les Membranes à Matrices Mixtes (MMM’s) sont des matériaux prometteurs pour la capture de CO2 en comparaison aux technologies actuelles telles que l’absorption par solvants aminés (monoéthanolamine). Les ‘Metal-Organic Frameworks’ (MOFs) sont des matériaux poreux cristallins envisagés pour être intégrés sous forme de nanoparticules aux polymères des MMM’s. Ils résultent de la combinaison de nœuds métalliques et de ligands organiques pour former des structures tridimensionnelle (3D) organisées. Ils possèdent divers avantages : des aires spécifiques et des volumes poreux élevés, des tailles de pores contrôlables, et pour certains une stabilité à l’eau. Les MOFs ont une chimie adaptable aux applications souhaitées contrairement aux adsorbants classiques tels que les charbons actifs, les zéolithes.D’une part, ce travail a eu pour objectif l’évaluation des performances de séparation du CO2 par des MOFs microporeux en vue des séparations CO2/N2 et CO2/CH4. Les interactions ‘gaz-adsorbant’ sont favorisées au sein des MOFs par : (1) une réduction de la taille de pores et du volume poreux pouvant engendrer des effets de confinements, de tamis moléculaire ou (2) par la présence de groupements de surface. En conséquence, ces paramètres peuvent contribuer à l’amélioration de la sélectivité du CO2 et ont été étudiés pour divers systèmes de MOFs microporeux. D’autre part, les paramètres texturaux (aire spécifique, volume poreux) et thermodynamiques (enthalpies d’adsorption) ont été corrélés aux quantités maximales de CO2 adsorbées au travers d’une approche quantitative de relation de structure-propriété pour établir des tendances linéaires
Mixte Matrix Membranes (MMM’s) are promising materials for CO2 capture compared to current technologies as absorption using amines solvents (monoéthanolamine). Metal-Organic Frameworks (MOFs) are crystalline porous materials which can be integrate under nanoparticles shape to polymer phase of MMM’s. They are built from metal nods and organic ligand to yield well-defined tridimensional structure (3D). They possess various advantages: high specific surface area and pore volume, tunable pore size and some of them are stable in presence of water. MOFs have a sustainable chemistry to targeted applications unlike traditional adsorbents as activated carbons, zeolites.On the one hand, this work aimed the assessment of CO2 separation performances of microporous MOFs for CO2/N2 and CO2/CH4 gas separations. The ‘gas-adsorbent’ interactions are favored in MOFs by: (1) a decrease of pore size, pore volume which can involve confinement effects, molecular sieve effects or (2) the presence of surface groups. Therefore, these factors can contribute to the CO2 selectivity improvement and have been studied for various microporous MOFs. On the other hand, textural (specific surface area, pore volume) and thermodynamic (adsorption enthalpy) parameters have been correlated to CO2 maximum excess uptakes through a quantitative structure-property approach to establish some linear trends

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Νοχός, Αργύριος. "Διερεύνηση της μετανάστευσης και της αποδέσμευσης αντιμικροβιακών ουσιών από πολυμερικές ίνες πολυλειτουργικών υφασμάτων". Thesis, 2008. http://nemertes.lis.upatras.gr/jspui/handle/10889/1342.

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Η παρούσα εργασία μελετά την ανάπτυξη ενός ευέλικτου συστήματος αντιμικροβιακής προστασίας για εφαρμογή σε είδη ρουχισμού και υφάσματα οικιακής χρήσης. Πιο συγκεκριμένα αναπτύχθηκαν διασυνδεδεμένα πολυμερικά νανοσφαιρίδια πολυστυρολίου-διβινυλοβενζολίου στα οποία ενσωματώθηκε Triclosan, μία ευρέος φάσματος εμπορική αντιμικροβιακή ουσία. Σημειώνεται ότι στο πλαίσιο ανάσχεσης των ενδονοσοκομειακών λοιμώξεων η ανάπτυξη αντιμικροβιακών νοσοκομειακών στολών, σεντονιών και άλλων σχετικών κλωστοϋφαντουργικών προϊόντων αποτελούν τις τελευταίες δεκαετίες αντικείμενο έντονου επιστημονικού ενδιαφέροντος. Το μέγεθος των νανοσωματιδίων βρέθηκε μετά από εξέταση με ηλεκτρονική μικροσκοπία σάρωσης (SEM) και δυναμική σκέδαση φωτός (DLS) να κυμαίνεται μεταξύ 35-350 nm ανάλογα την σύσταση. H θερμική συμπεριφορά τους μελετήθηκε μέσω διαφορικής θερμιδομετρίας σάρωσης (DSC) και διαπιστώθηκε σημείο τήξεως στους ~425 οC. Χρησιμοποιώντας την φασματοσκοπία UVVis προσδιορίστηκε ο πραγματικός εγκλωβισμός του αντιμικροβιακού στο σύστημα κατά μέσο όρο σε ποσοστό ~72% του ονομαστικού και παρακολουθήθηκε ο ρυθμός αποδέσμευσης του σε διαλύματα αιθανόλης-νερού. Επιπλέον, τα σφαιρίδια που όπως διαπιστώθηκε παρουσιάζουν χαρακτηριστικά ελεγχόμενης αποδέσμευσης ενσωματώθηκαν σε μήτρες πολυπροπυλενίου οι οποίες υπό την μορφή φιλμ εφελκύστηκαν μονοαξονικά. Τέλος κάνοντας χρήση της δονητικής φασματοσκοπίας Raman εκτιμήθηκε ο μοριακός προσανατολισμός που επιβλήθηκε στα εφελκυσμένα φιλμ και συσχετίσθηκε με την παρατηρούμενη μείωση που επιτεύχθηκε στην κινητική αποδέσμευσης της εγκλωβισμένης δραστικής ουσίας. Το πρώτο κεφάλαιο της παρούσας εργασίας ασχολείται με το πρόβλημα της μικροβιακής επιμόλυνσης υφασμάτων, τις διάφορες λύσεις που έχουν προταθεί κατά καιρούς και τέλος αναλύει τον στόχο της παρούσας εργασίας. Στο δεύτερο κεφάλαιο επεξηγείται η έννοια της ελεγχόμενης αποδέσμευσης και περιγράφονται οι διάφορες κατηγορίες συστημάτων ελεγχόμενης χορήγησης μαζί με χαρακτηριστικά παραδείγματα. Τα νανοσωματίδια, η σύστασή, οι μοναδικές ιδιότητες, οι εφαρμογές και οι διάφοροι τρόποι σύνθεσης και χαρακτηρισμού τους συζητούνται στο τρίτο κεφάλαιο. Το τέταρτο κεφάλαιο αναφέρει πληροφορίες για τα υλικά και επεξηγεί τις τεχνικές που χρησιμοποιήθηκαν στην σύνθεση, την επεξεργασία και τον χαρακτηρισμό των νανοσωματιδίων και των μιγμάτων τους. Τέλος στο πέμπτο κεφάλαιο παρουσιάζονται τα αποτελέσματα των πειραμάτων που πραγματοποιήθηκαν και ακολουθεί ο σχολιασμός τους.
The present thesis studies the development of a versatile system of antimicrobial protection for use in clothing and household products. In particular Triclosan incorporated crosslinked polystyrenedinylbenzene nanobeads were developed; triclosan is a widely used antimicrobial agent. It is noted that the health hazards arising during nosocomial treatment due to infections caused by microbial pathogens and the means to protect oneself against such threats have become the subject of many research activities during the last few decades. The size of the nanoparticles after examination with scanning electron microcopy (SEM) and dynamic light scattering (DLS) was found to vary between 35-350 nm depending on the system formulation. Their thermal behavior was studied with differential scanning calorimetry (DSC) and their melting point was measured at ~425 oC. Using UV-Vis spectroscopy the real encapsulation efficiency of the antimicrobial in the system was determined at ~72% and its release kinetics were studied in a water-ethanol solution. The nanobeads possess controlled release properties; they were furthermore incorporated into polypropylene matrixes which were uniaxially drawn in film form. Finally utilizing polarized Raman spectra, the draw induced molecular orientation of the films was correlated to the relevant variation of the related antimicrobial release kinetics. The first chapter of the present thesis reviews the textile microbial infections and the various solutions that have been proposed showing up the specific research goal targeted. In the second chapter the meaning of controlled release is explained and the basic system categories involved are presented along with characteristic examples. The nanoparticles, their composition, special attributes, applications, synthesis and characterization techniques are the subject of the third chapter. The fourth chapter reports information about the materials and the methods used in the synthesis, postprocessing and characterization of the nanoparticles and their blends. Finally the last chapter presents the experimental results and relevant comments.

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Tseng, Yung-Yuan, and 曾泳源. "Warm-Keeping Effect of Textile Knitted by Nanoparticle-Contained Fabric." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/56597127834568178612.

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碩士
國立雲林科技大學
機械工程系碩士班
94
In recent years ,there are various applications of nanotechnology to improve textile warm-keeping ability, but the theory has not been studied completely yet. This study aims at the bio-ceramics fabric warm-keeping principle and explains this phenomenon by the energy exchange in the micro-scale to set up a model can extend its application.

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Mishra, Anu. "Studies on multi-functional properties of doped TiO2 nanoparticle coated cotton fabric." Thesis, 2018. http://eprint.iitd.ac.in:80//handle/2074/8015.

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Paul, Sangita. "Silver nanoparticle dispersions for antimicrobial finishing of textiles." Thesis, 2013. http://localhost:8080/xmlui/handle/12345678/6766.

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Le, Hoai Nga. "A concept for nanoparticle-based photocatalytic treatment of wastewater from textile industry." Doctoral thesis, 2017. https://tud.qucosa.de/id/qucosa%3A30121.

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Industrial wastewater, such as the effluents from textile and garment companies, may contain toxic organic pollutants, which resist conventional wastewater treatment. Their complete and environmentally friendly degradation requires innovative technologies. Photocatalysis, an advanced oxidation process, can serve this purpose. Since 1972, when the photocatalytic activity of titanium dioxide was first noticed, photocatalysis has drawn the attention of scientists and engineers but it has not yet been widely applied in industrial practice. This is mainly related to the challenges of up-scaling from laboratory experiments to large production sites. The main goal of this thesis is to develop a concept of nanoparticle-based photocatalysis for the treatment of wastewater. Ideally, process parameters should be adjustable and process conditions should be well-defined. These constraints are prerequisite for establishing process models and comparing the photocatalytic efficiency of different photocatalysts or for different pollutants. More importantly, the configuration should be scalable, in order to cover a wide spectrum of applications. In response to these requirements, this thesis introduces a new reactor concept for photocatalytic wastewater treatment, which relies on finely dispersed photocatalysts as well as uniform and defined process conditions with regard to illumination and flow. The concept was realized in a photocatalytic setup with an illuminated flow reactor. The flow channel has a rectangular cross section and meanders in a plane exposed to two dimensional illumination. Crucial process parameters, e.g., volumetric flow rate and light intensity, can be adjusted in a defined manner. This facilitates the study on the photocatalytic degradation of different organic pollutants in the presence of various photocatalytic materials under arbitrary illumination. The thesis provides a comprehensive description of the operational procedures necessary to run photocatalytic reactions in the experimental setup. It includes three main steps: i) dispersion of photocatalysts, ii) equilibration with respect to pollutant adsorption and iii) accomplishing the photocatalytic reaction. Samples are collected in a mixing tank for online or offline analysis. The proceeding decrease in the concentration of organic pollutant is used to assess the activity of the photocatalytic materials. A particular focus lies on the first of these steps, the dispersion of photocatalysts, because it is ignored in most studies. Typically, photocatalysts are in an aggregated state. The thesis demonstrates that type, intensity and energy of dispersion exert a crucial influence on size and morphology of the photocatalyst particles and, thus, on their optical properties and, accordingly, macroscopic photocatalytic behavior. Apart from this, a proper dispersion is necessary to reduce speed of gravitational solid-liquid separation, at best, to prevent catalyst sedimentation and to avoid misleading results. The photocatalytic performance was intensively investigated for the color removal of a model dye substance, methylene blue. Commercial titanium dioxide nanoparticles, widely explored in literature, were used as a photocatalyst. Their characteristics (size, morphology, stability and optical properties) were determined. Photocatalytic experiments were carried out under UV irradiation. Influences of different factors, including the concentration of the photocatalyst, the concentration of the organic compounds, light intensity, optical pathlength and pH were examined. The degradation was quantified via the decrease of methylene blue concentration. This conversion is, however, an immediate result influenced by all process parameters, e.g., the volume, the light intensity, the optical pathlength. Hence, kinetic models on macroscopic and microscopic levels are established. Normalizations with respect to process conditions are proposed. The apparent reaction kinetics are traced back to volume- and intensity-related reaction rate constants, and the reaction rate constant at the illuminated surface of the reactor. Additionally, the model is modified to be used for time-variant UV intensities, as encountered for solar photocatalysis. These achievements allow for a comparison of the experimental results from different laboratories. Moreover, they are prerequisite for the translation of laboratory results into large scale plants. Selected case studies for further applications are introduced. The photocatalytic degradation of different organic molecules (one antibiotic and two commercial dyes) with different photocatalytic materials (commercial nanomaterials and self-synthesized magnetic particles) under artificial or natural light sources was performed. Additionally, photocatalysis was studied in a realistic application. Preliminary tests with dye solutions of a textile company in Danang, Vietnam, impressively showed the feasibility of wastewater treatment by means of photocatalysis. Based on the reported capacity of wastewater in the current treatment plant of the company, the necessary process parameters were assessed. The rough estimation showed that photocatalysis can improve the working ability of the current wastewater treatment plant. In conclusion, this thesis presents a concept for wastewater treatment by slurry photocatalysis. As the process conditions are adjustable and definable, the process can be ideally performed in laboratories for research purposes, where different materials need to be tested and the working volume can be lower than hundreds of milliliters. The photocatalytic configuration is expected to work with a capacity of hundreds of liters, although appropriate experimental evidences are reserved for further up-scaling studies.

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Barbosa, Tiago Manuel Martinho. "Photocatalytic and self-cleaning functionalized textiles with TiO2 nanoparticles and thin films." Master's thesis, 2014. http://hdl.handle.net/1822/50024.

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Анотація:

Dissertação de mestrado em Biofísica e Bionanossistemas
Nanocoatings applied in textile finishing are a very attractive way to add value to dayto- day products offering an interesting set of important and differentiated properties. The photocatalytic activity of titanium dioxide (TiO2) based nanomaterials for textile applications has been identified as a strategic vector with great industrial impact. The development of self-cleaning and antimicrobial surface finishes in common textiles has the potential to be used as a prophylactic measure to reduce the infection rates in hospitals as well as reduce the environmental impact of washing processes. In this research work Pulsed DC Magnetron Sputtering technique was used to deposit TiO2 thin films onto glass and Poly(lactic acid) (PLA) and cotton based substrates. On the other hand, TiO2 nanoparticles were also deposited on the textile surfaces by means of a dip-coating process. The main goal of the research work was the production of TiO2 - based functionalized textile substrates without changing its surface characteristics such as aesthetic and sensorial (e.g. touch feeling) properties. The applied textile finishing techniques in this research work need less to none of the solvents or surfactants commonly used in the industry leading to a cleaner production process reducing significantly the environment pollution. The samples were characterized by using Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM), Contact Angle measurements and UV – visible Spectroscopy techniques. The photocatalytic activity of the samples was studied by measuring the Methylene Blue (MB) degradation over time as a result of the catalyst exposure to ultraviolet (UV) radiation and its correlation with the initial concentration. This effect is directly correlated to the photocatalytic efficiency and rate of the samples. The self-cleaning activity was also evaluated by a wine stain removal test under UV light exposure.
Nanorevestimentos aplicados no processo de acabamento de materiais têxtil são uma forma muito atrativa para adicionar valor a produtos do quotidiano conferindo-lhes um conjunto de propriedades importantes e inovadoras. A atividade fotocatalítica dos nanomateriais à base de dióxido de titânio (TiO2) em aplicações têxteis tem sido identificado como um vetor estratégico com um elevado impacto industrial. O desenvolvimento de superfícies com acabamentos autolimpantes e antimicrobianos em têxteis comuns tem o potencial de ser utilizado como medida profilática na redução de taxas de infeção em ambientes hospitalares e reduzir o impacto ambiental relacionado com os processos de lavagem. Neste trabalho de investigação foi utilizada a técnica de pulverização catódica em magnetrão utilizando fonte DC pulsada para depositar filmes finos de TiO2 em substratos de vidro e de materiais têxteis baseados em ácido poliláctico (PLA) e algodão. Por outro lado, depositaram-se nanopartículas de TiO2 em substratos têxteis pela utilização de um processo de imersão. O principal objectivo do trabalho de investigação foi a produção de materiais têxteis com acabamentos de TiO2 sem que ocorresse a alteração das características superficiais tais como propriedades estéticas e sensoriais (e.g. sensação ao toque). As técnicas de acabamento superficial nos materiais têxteis utilizados neste trabalho de investigação utilizam uma quantidade inferior de solventes e tensioativos comparativamente com as normalmente utilizadas na indústria reduzindo, significativamente, a poluição ambiental. As amostras foram caracterizadas pela utilização das técnicas de Microscopia Electrónica de Varrimento (MEV), Microscopia de Força Atómica (MFA), medição do ângulo de contacto e Espectroscopia UV-Visível. A atividade fotocatalítica das amostras foi estudada inicialmente pela medição da degradação do Azul-de-metileno ao longo do tempo em resultado da exposição do catalisador à radiação ultravioleta (UV) e a sua correlação com a concentração inicial. Este efeito é diretamente correlacionado com a eficiência e velocidade fotocatalítica das amostras. A actividade autolimpante foi testada através de um teste de remoção de uma nódoa de vinho de um substrato têxtil funcionalizado com TiO2 exposto à luz UV sendo medido o valor de K/S correspondente ao longo do tempo de exposição.

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34

Pinto, Tânia Vanessa Oliveira. "Photoswitchable silica nanoparticles for the production of light responsive smart textiles: from fabrication to coating technology." Doctoral thesis, 2017. https://repositorio-aberto.up.pt/handle/10216/105967.

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35

Pinto, Tânia Vanessa Oliveira. "Photoswitchable silica nanoparticles for the production of light responsive smart textiles: from fabrication to coating technology." Tese, 2017. https://repositorio-aberto.up.pt/handle/10216/105967.

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36

Yang, Yu-Wei, and 楊育瑋. "Preparation of Conductive Textiles Containing Polypyrrole and Metal Nanoparticles by Diffusion-Oxidation Method and Property Characterization." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/d4pus7.

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Анотація:

碩士
國立臺北科技大學
有機高分子研究所
96
Fabrics including cotton, nylon 6 and poly(ethylene terephthalate) were pre-adsorbed metal nanoparticles(Au、Ag and Cu) and diffused with pyrrole. These fabrics were chemically oxidized by FeCl3 in water. Polypyrrole has been found incorporating into interior of fibers and spacing between fibers. The resistivities of polypyrrole and nanoparticles contained fabrics were lower than those of fabrics containing polypyrrole(30 to 100 Ω/square). The existence of metal nanoparticles in fabric was identified by atomic absorption spectroscopy and electron dispersive spectroscopy. Gold loading of the conductive fabric was high comparing to two other metals. Dispersion of preadsorbed metal nanoparticles on the surface of fibers of pristine fabric was good according to images taken from electron scanning microscope. Electromagnetic shielding of the conductive fabrics were significant 8-26dB(nylon 6)、7-15dB(PET) and 5-9dB(cotton)，although resistance of polypyrrole lose during laundry was fair for above textiles.

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37

Chiou, Ya-Huei, and 邱雅惠. "Preparation of Conductive Textiles Containing Polypyrrole and Metal Nanoparticles by Chemical Oxidation Method and Property Characterization." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/2s3926.

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Анотація:

碩士
國立臺北科技大學
有機高分子研究所
96
Pyrrole with various amount of metal nanoparticles including Au、Ag and Cu was chemically oxidized by iron(III) chloride hexahydrate in water and deposited as a polymer film on the surface of fabrics(cotton and nylon 6 and PET).The surface resistivities of above conductive textiles were measured by four-point probe method. The existence of metal on the fabric was identified using atomic absorption spectroscopy and energy dispersive spectrometry. It indicated that the surface resistivities of metal nanoparticles and polypyrrole coated cotton fabric was lower than that of polypyrrole cotton fabric. The same kind of trend was found for metal nanoparticles and polypyrrole coated nylon 6 or PET fabric. The surface of polypyrrole-coated fibers of metal-containing fabric was smooth according to scanning electron microscopic images. Electromagnetic shielding and resistance of polypyrrole loss for laundry were fair for the conductive fabrics prepared by above method.

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38

Ali, Md S. Wazed. "Synthesis and characterization of chitosan nanoparticle and its application on textiles using layer-by-layer self- assembly approach for antimicrobial activity." Thesis, 2011. http://localhost:8080/xmlui/handle/12345678/3920.

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39

Rodrigues, Joana Mendes. "Desenvolvimento de metodologias para avaliação de nanomateriais incorporados em diferentes substratos têxteis." Master's thesis, 2017. http://hdl.handle.net/1822/54863.

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Анотація:

Dissertação de mestrado integrado em Engenharia Biológica (área de especialização em Tecnologia Química e Alimentar)
Nos últimos anos, tem-se observado um crescente interesse em têxteis funcionais, o que tem levado a indústria têxtil a apostar em novos materiais e processos baseados na nanotecnologia. No entanto, a incorporação de nanomateriais para conferir funcionalidades ao têxtil, pode estar também associada ao aparecimento de efeitos adversos quando em contacto com o ser humano e ainda do ponto de vista ambiental. Uma das maiores preocupações no caso dos têxteis é a possível libertação dos nanomateriais, a qual depende muito da estabilidade dos mesmos após a sua incorporação num substrato têxtil. Desta forma, é importante identificar e quantificar estes nanomateriais ligados covalentemente ao substrato, para avaliar a sua estabilidade e possível libertação. Assim, este projeto teve como principal objetivo o desenvolvimento de metodologias expeditas para quantificar nanomateriais incorporados em substratos têxteis e consequentemente, avaliar a sua estabilidade e resistência a processos de lavagem. Para a concretização dos objetivos propostos, numa primeira fase, funcionalizou-se um substrato têxtil 100% algodão com duas formulações de nanopartículas de naturezas distintas, designadamente nanopartículas de base proteica (NPs PA) e nanopartículas de um polímero sintético (NPs PB). Após a funcionalização, quantificaram-se as nanopartículas incorporadas no têxtil através de métodos de espetrofotometria de absorção para as NPs PA, incluindo o método de Bradford e o método de Acid Orange, e recorreu-se ao método da titulação ácido-base para quantificação das NPs PB. Para estudar a resistência da funcionalidade do têxtil às lavagens, procedeu-se à funcionalização de provetes têxteis com as nanopartículas e diferentes agentes de ligação, sendo estes posteriormente submetidos a diferentes condições de lavagem. Os resultados mostraram que o método da titulação é viável para a quantificação das NPs PB incorporadas no têxtil. Quanto à quantificação de NPs PA incorporadas no têxtil apenas o método de Acid Orange apresentou resultados viáveis. Contudo, verificou-se ao longo do desenvolvimento do projeto que estes métodos podem ser influenciados por diversos fatores, os quais terão de ser tidos em conta aquando a quantificação das nanopartículas. Através das técnicas de caracterização de Espetroscopia de Infravermelho com Transformadas de Fourier com Refletância Total Atenuada (FTIRATR) e de microscopia eletrónica de varrimento (SEM) foi possível detetar a presença de ambas NPs poliméricas nos têxteis funcionalizados. Nos ensaios da durabilidade às lavagens os resultados obtidos pelos métodos acima referidos indicaram que nenhum dos agentes de ligação testados aumentava a resistência das nanopartículas às lavagens, verificando-se que estas se libertavam do têxtil logo após a lavagem de processo, no qual apenas se utiliza água e temperatura.
Over the last years, there has been a growing interest in functional textiles, which has led the textile industry to invest in new materials and processes based on nanotechnology. However, the incorporation of nanomaterials to promote textile functionalities may also be associated with adverse effects when in contact with human skin, well as from an environmental point of view. One of the major concerns in the case of textiles is the possible release of nanomaterials, which highly depends on the stability after their incorporation into a textile substrate. Therefore, it is important to identify and quantify the nanomaterials covalently bounded to the substrate in order to evaluate their stability and possible release. Thus, the main purpose of this project was to develop prompt methodologies to quantify nanomaterials incorporated in textile substrates and consequently, to evaluate their stability and washing resistance. In order to accomplish the proposed objectives, at a first stage, a 100% cotton textile substrate was functionalized with two formulations of nanoparticles of different natures, namely protein-based nanoparticles (NPs PA) and nanoparticles of a synthetic polymer (NPs PB). Afterwards, the textiles functionalized with NPs PA were quantified by absorption spectrophotometry methods, including the Bradford and the Acid Orange methods, whereas the acid-base titration method was used for quantification of the samples functionalized with NPs PB. In order to study the washing resistance of the textiles after functionalization, some textile samples were functionalized with nanoparticles and different crosslinking agents, being afterwards subjected to different washing conditions. The results showed that the titration method is suitable for the quantification of NPs PB incorporated in the textile. As for the quantification of NPs PA incorporated in the textile only the Acid Orange method presented viable results. Nevertheless, throughout the project development, it was verified that these methods can be influenced by several factors, which will need to be considered when quantifying the nanoparticles. The characterization techniques of Infrared Spectroscopy with Fourier Transform with Attenuated Total Reflectance (FTIR-ATR) and Scanning electron microscope (SEM) allowed the detection of the presence of both polymer nanoparticles in the functionalised textiles. Regarding the washing tests, the results achieved by the abovementioned methods indicated that none of the crosslinking agents tested increased the nanoparticles’ resistance to the washing process. Indeed, it was found that they were released from the textile immediately after the washing process, using only water and temperature.

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Дисертації з теми "Textile nanoparticles"

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