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Desarrollo y caracterización de biocomposites con cáscara de almendra para el sector jugueteroIbáñez García, Ana 02 September 2021 (has links)
[ES] En los últimos años, se ha incrementado la sensibilidad en torno a las cuestiones ambientales derivadas del uso de los materiales poliméricos basados en el petróleo y el impacto de éstos en el medio ambiente.
La concienciación social y ambiental adquirida por parte de los consumidores hace que industrias tradicionales, como la del juguete, donde el uso del plástico está ampliamente extendido, desee adaptarse voluntariamente a la demanda del mercado y las empresas quieran desarrollar nuevas líneas de producto empleando materiales más ecológicos y sostenibles.
El principal objetivo de esta tesis doctoral es el desarrollo y caracterización de biocomposites (biocompuestos) obtenidos a partir de una matriz polimérica procedente de fuentes renovables y biodegradable, concretamente almidón termoplástico (TPS), y como relleno, cáscara de almendra en polvo (ASP), aptos para ser procesados por inyección cuyas propiedades mecánicas, térmicas y estéticas permitan su uso en el sector del juguete.
En un primer bloque, esta investigación estudia la influencia de la variedad de cáscara de almendra en las propiedades finales del biocomposite TPS/ASP desarrollado. Para ello, se seleccionan cinco variedades de almendra: Desmayo Rojo, Largueta, Marcona, Mollar y una mezcla comercial de variedades desconocidas, ya suministrada en formato polvo. También se estudia la influencia del tamaño de partícula de dicha carga (menor a 0.05 mm, 0.05<p<0.08 mm, 0.08<p<0.125 mm y 0.125<p<0.250 mm) considerando una cantidad fija de ASP (30 % en peso). Finalmente, se analiza el efecto del contenido de ASP (5-30 % en peso). Para ello, los diferentes biocomposites son fabricados mediante técnicas convencionales de extrusión e inyección. Se emplea una metodología basada en diferentes técnicas experimentales para la determinación de las propiedades mecánicas (ensayos de tracción, flexión, impacto Charpy y dureza Shore D), propiedades térmicas (análisis calorimétrico (DSC) y termogravimétrico (TGA)), medidas colorimétricas (CIELab) y análisis morfológico (SEM).
En general, de este primer bloque se concluye que, la adición de ASP al TPS aumenta la rigidez del material y disminuye su deformación a rotura, la resistencia al impacto y la resistencia térmica con respecto a la matriz polimérica TPS. La incorporación de ASP proporciona un acabado similar a la madera.
Una vez seleccionada la variedad, el tamaño de partícula y el contenido de ASP más adecuado, se considera mejorar la interacción carga/matriz con objeto de incrementar las propiedades mecánicas que se han visto afectadas por la adición de la carga. Los métodos de compatibilización que se han llevado a cabo para ello han sido mediante la incorporación de sustancias de origen renovable. En concreto, los compatibilizantes de origen renovable empleados en esta tesis doctoral son tres aceites vegetales epoxidados (EVOs): el aceite de linaza epoxidado (ELO), el aceite de soja epoxidado (ESBO) y el aceite de maíz epoxidado (ECO). Los diferentes EVOs se han incorporado entre 5-20 phr. La caracterización de las propiedades de los bicomposites desarrollados se realiza de forma análoga a los obtenidos en el primer bloque. Los resultados obtenidos muestran una notable mejora de las propiedades mecánicas con el empleo de estos compatibilizantes derivados de aceites vegetales. Además, la adición de estas sustancias tiene un efecto estabilizante en la desintegración del material.
Finalmente, se estudia si es posible reprocesar el TPS y el biocomposite TPS/ASP y cómo afecta el reprocesado de estos biomateriales a sus propiedades finales (estéticas, mecánicas y térmicas). A pesar de la progresiva degradación del material, en ambos casos, es técnicamente factible volver a procesar el material al menos tres veces sin necesidad de incorporar material virgen. / [CA] En els últims anys, s'ha incrementat la sensibilitat entorn a les qüestions ambientals derivades de l'ús dels materials polimèrics basats en el petroli i l'impacte d'aquests en el medi ambient.
La conscienciació social i ambiental adquirida per part dels consumidors fa que indústries tradicionals, com la del joguet, on l'ús del plàstic està àmpliament estés, desitge adaptar-se voluntàriament a la demanda del mercat i les empreses vullguen desenvolupar noves línies de producte emprant materials més ecològics i sostenibles.
El principal objectiu d'aquesta tesi doctoral és el desenvolupament i caracterització de biocomposites obtinguts a partir d'una matriu polimèrica procedent de fonts renovables i biodegradable, concretament almidó termoplàstic (TPS), i com a càrrega, pols de corfa d'ametla (ASP), aptes per a ser processats per injecció, les propietats mecàniques, tèrmiques i estètiques de les quals, permeten el seu ús en el sector del joguet.
En un primer bloc, aquesta investigació estudia la influència de la varietat de corfa d'ametla, en les propietats finals del biocomposite de TPS/ASP desenvolupat. Per a això, se seleccionen cinc varietats d'ametla: Desmai Roig, Largueta, Marcona, Mollar i una mescla comercial de varietats desconegudes, ja subministrada en format de pols. També s'estudia la influència del tamany de partícula (menor a 0.05 mm, 0.05<p<0.08 mm, 0.08<p<0.125 mm i 0.125<p<0.250 mm) considerant una quantitat fixa d'ASP (30 % en pes). Finalment, s'analitza l'efecte del contingut d'ASP (5-30 % en pes). Per a això, els diferents biocomposites són fabricats mitjançant tècniques convencionals d'extrusió i injecció. S'empra una metodologia basada en diferents tècniques experimentals per a la determinació de les propietats mecàniques (assajos de tracció, flexió, impacte Charpy, duresa Shore D), propietats tèrmiques (anàlisis calorimètric (DSC) i termogravimètric (TGA), mesures colorimètriques (CIELab) i anàlisi morfològic (SEM).
D'aquest primer bloc es conclou que, l'addició d'ASP al TPS augmenta la rigidesa del material, disminuïx la seua deformació a ruptura, la resistència a l'impacte i la resistència tèrmica respecte a la matriu polimèrica TPS. La incorporació d'ASP, proporciona un acabat similar a la fusta.
Una vegada seleccionada, la varietat, el tamany de partícula i el contingut d'ASP més adequat, es considera millorar la interacció càrrega/matriu a fi d'incrementar les propietats mecàniques que s'han vist afectades per l'addició de la càrrega. Les tècniques de compatibilització que s'han dut a terme en aquest treball ha sigut mitjançant la incorporació de substàncies d'origen renovable. En concret, els compatibilitzants d'origen renovable utilitzats en aquesta tesi doctoral són tres olis vegetals epoxidats (EVOs): l'oli de llinosa epoxidat (ELO), l'oli de soja epoxidat (ESBO) i l'oli de panís epoxidat (ECO). Els diferents EVOs s'han incorporat entre 5-20 phr. La caracterització de les propietats dels bicomposites desenvolupats es realitza de forma anàloga als obtinguts en el primer bloc. Els resultats obtinguts mostren una notable millora de les propietats mecàniques amb l'ús d'estos compatibilitzants derivats d'olis vegetals. A més, l'addició de EVOs té un efecte estabilitzant en la desintegració del material.
Finalment, si és possible reprocessar el TPS i el biocomposite TPS/ASP i com afecta el reprocessat d'estos biomaterials a les seues propietats finals (estètiques, mecàniques i tèrmiques). Malgrat la progressiva degradació del material, en ambdós casos, és tècnicament factible tornar a processar el material almenys tres vegades sense necessitat d'incorporar material verge. / [EN] In recent years, there has been a growing awareness of the environmental issues arising from the use of petroleum-based polymeric materials and their impact on the environment.
The social and environmental awareness consumers now have makes traditional industries, such as the toy industry, where the use of plastic is widespread, want to voluntarily adapt to market demand and develop new product lines using more ecological and sustainable materials.
The main objective of this doctoral thesis is the development and characterisation of biocomposites developed from a polymeric matrix of renewable and biodegradable sources, specifically thermoplastic starch (TPS), and as a filler, almond shell powder (ASP), suitable for processing by injection moulding whose thermal-mechanical and aesthetic properties allow their use in the toy sector.
In the first block, the influence of the variety of almond shells on the final properties of the polymeric matrix is studied. For this purpose, five varieties are selected: Desmayo Rojo, Largueta, Marcona, Mollar, and a commercial mixture of unknown varieties, already supplied in powder form. The influence of particle size (smaller than 0.05 mm, 0.05<p<0.08 mm, 0.08<p<0.125 mm and 0.125<p<0.250 mm) is also studied considering a fixed amount of ASP (30 %). Finally, the effect of ASP content (5-30 %) is analysed. For this purpose, the different biocomposites are manufactured by conventional extrusion and injection techniques. A methodology based on different experimental techniques is used to determine the mechanical properties (tensile, flexural, Charpy impact, Shore D hardness), thermal properties (calorimetric analysis (DSC), and thermogravimetric analysis (TGA), colorimetric measurements (CIELab), and morphological analysis (SEM).
In general, it is concluded from this first block that the addition of ASP to the TPS increases the stiffness of the material, but then decreases its deformation at break, impact resistance and thermal resistance in respect to the TPS polymeric matrix. The addition of ASP provides a wood-like finish.
Once the most suitable variety, particle size, and ASP content have been selected, consideration is given to improving the particle/matrix interaction. The compatibilisation techniques carried out in this work have been through the incorporation of substances of renewable origin. The compatibilisers of renewable origin used in this doctoral thesis are three epoxidised vegetable oils (EVOs): epoxidised linseed oil (ELO), epoxidised soybean oil (ESBO) and epoxidised corn oil (ECO). The different EVOs have been incorporated between 5-20 phr. The results obtained show a remarkable improvement of the mechanical properties with the use of vegetable oil-derived compatibilisers. Moreover, the addition of EVOs has a stabilising effect on the disintegration of the material.
Finally, it is studied how the reprocessing of TPS and TPS/ASP biocomposite affects their final characteristics. Despite the progressive degradation of the material, in both cases, it is technically feasible to reprocess the material at least three times without the need to incorporate virgin material. / Ibáñez García, A. (2021). Desarrollo y caracterización de biocomposites con cáscara de almendra para el sector juguetero [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172341
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Management strategy of landfill leachate and landfill gas condensateZhao, Renzun 15 October 2012 (has links)
Studies were conducted to evaluate the impact of landfill leachate discharge on the operation of waste water treatment plants (WWTPs). Two aspects of interferences were found: one is UV quenching substances, which are bio-refractory and able to penetrate the biological treatment processes, consequently interfere the UV disinfection in WWTPs. The other one is organic nitrogen, which can pass the nitrification-denitrification process and contribute to the effluent total nitrogen (TN). Also, treatability study was conducted for landfill gas (LFG) condensate. In a laboratory study, leachate samples were fractionated into humic acids (HA), fulvic acids (FA) and Hydrophilic (Hpi) fractions, the specific UV254 absorbance (SUVA254) of the three fractions follows: HA > FA > Hpi. However, the overall UV254 absorbance of the Hpi fraction was important because there was more hydrophilic organic matter than humic or fulvic acids. It was found that the size distribution of the three fractions follows: HA > FA > Hpi. This indicates that membrane separation following biological treatment is a promising technology for the removal of humic substances from landfill leachates. Leachate samples treated in this manner could usually meet the UV transmittance requirement of the POTWs. Also, nitrogen species in landfill leachates under various stabilization states were investigated. Although the effect of landfill stabilization state on the characteristics of organic matter and ammonia is well documented, there are few investigations into the landfill leachate organic nitrogen under different stabilization stages. Ammonia was found to leach out slower than organic matter and can maintain a constant level within the first a couple of years (< 10 years). The concentration and biodegradability of organic nitrogen were found to decrease with landfill age. A size distribution study showed that most of organic nitrogen in landfill leachates is < 1 kDa. The protein concentration was analyzed and showed a strong correlation with the organic nitrogen. Different slopes of regression curves of untreated and treated leachates indicate that protein is more biodegradable than the other organic nitrogen species in landfill leachates. XAD-8 resin was employed to isolate the hydrophilic fraction of leachate samples, hydrophilic organic nitrogen was found to be more biodegradable/bioavailable than the hydrophobic fractions. Furthermore, biological and physical-chemical treatment methods were applied to a landfill biogas (LFG) condensate to explore the feasible treatment alternatives for organic contaminant and arsenic removal efficiency. Sequencing batch reactor (SBR) showed effectiveness for the degradation of organic matter, even in an environment containing high levels of arsenic. This indicated a relatively low toxicity of organic arsenic as compared to inorganic arsenic. However, for arsenic removal, oxidation-coagulation, including biological oxidation, conventional oxidation and advanced oxidation followed by ferric salt coagulation, and carbon adsorption were not effective for what is believed to be tri-methyl arsenic. Among these, advanced oxidation-coagulation showed the best treatment efficiency (15.1% removal). Only reverse osmosis (RO) could reduce the arsenic concentration to an acceptable level to meet discharge limits. These results implied high stability and low toxicity of organic arsenic. / Ph. D.
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Development of Novel Biomimetic Electroactive Environments with Bioactive Molecules for Musculoskeletal RegenerationAparicio Collado, José Luis 20 July 2023 (has links)
Tesis por compendio / [ES] El sistema musculoesquelético tiene una capacidad de regeneración limitada. Las pérdidas importantes de tejido no se pueden regenerar, lo que provoca necrosis y deterioro funcional. Los tratamientos tradicionales basados en implantes o trasplantes no han demostrado ser del todo exitosos, con múltiples efectos secundarios como inmunogenicidad o rechazos. Por ello, es muy importante desarrollar nuevas alternativas para tratar la degeneración muscular. La ingeniería tisular combina biomateriales, células y agentes bioactivos para desarrollar constructos biológicos biocompatibles donde las células encuentran un entorno que imita sus condiciones in vivo para crecer, proliferar y diferenciarse en tejido muscular y restaurar su funcionalidad.
Los biomateriales conductores son de particular interés en tejidos electro-sensibles como es el caso del sistema musculoesquelético. Se ha demostrado que los polímeros conductores (polipirrol, polianilina, etc.), los materiales de carbono (grafeno, óxido de grafeno reducido, etc.) y los nanomateriales metálicos mejoran la diferenciación muscular, incluso sin estimulación eléctrica externa. Además, diferentes moléculas bioactivas como factores de crecimiento (FGF-2, IGF-1, etc.) o iones inorgánicos "terapéuticos" (zinc, magnesio, etc.) son alternativas para potenciar la diferenciación celular en diferentes tejidos.
Por lo tanto, la combinación de biomateriales conductores y moléculas bioactivas para mejorar la regeneración muscular representa una gran oportunidad en la ingeniería de tejidos musculares. El objetivo de este proyecto de tesis es desarrollar y caracterizar nuevos biomateriales electroactivos con diferentes composiciones, estructuras y propiedades y evaluar su potencial para tratar la regeneración musculoesquelética, así como la combinación de estos biomateriales electroactivos con iones inorgánicos buscando descubrir nuevas sinergias biomateriales conductores-iones terapéuticos en términos de diferenciación muscular.
¿ / [CA] El sistema musculoesquelètic té una capacitat de regeneració limitada. Les pèrdues importants de teixit no es poden regenerar, cosa que provoca necrosi i deteriorament de la funcionalitat. Els tractaments tradicionals basats en implants o trasplantaments no han demostrat ser del tot exitosos, amb múltiples efectes secundaris com ara immunogenicitat o rebutjos. Per això, és molt important desenvolupar noves alternatives per tractar la degeneració muscular. L'enginyeria tissular combina biomaterials, cèl·lules i agents bioactius per desenvolupar constructes biològics biocompatibles on les cèl·lules troben un entorn que imita les seves condicions in vivo per créixer, proliferar i diferenciar-se en teixit muscular i restaurar-ne la funcionalitat. Els biomaterials conductors són de particular interès en teixits electrosensibles com és el cas del sistema musculoesquelètic. S'ha demostrat que els polímers conductors (polipirrol, polianilina, etc.), els materials de carboni (grafè, òxid de grafè reduït, etc.) i els nanomaterials metàl·lics milloren la diferenciació muscular, fins i tot sense estimulació elèctrica externa. A més, diferents molècules bioactives com a factors de creixement (FGF-2, IGF-1, etc.) o ions inorgànics "terapèutics" (zinc, magnesi, etc.) són alternatives per potenciar la diferenciació cel·lular en diferents teixits. Per tant, la combinació de biomaterials conductors i molècules bioactives per millorar la regeneració muscular representa una gran oportunitat a l'enginyeria de teixits musculars. L'objectiu d'aquest projecte de tesi és desenvolupar i caracteritzar nous biomaterials electroactius amb diferents composicions, estructures i propietats i avaluar-ne el potencial per tractar la regeneració musculoesquelètica, així com la combinació d'aquests biomaterials electroactius amb ions inorgànics buscant descobrir noves sinergies biomaterials conductors-ions terapèutics en termes de diferenciació muscular. / [EN] The musculoskeletal system can self-regenerate in a limited way. Major tissue losses cannot be regenerated, resulting in necrosis and functional impairment. Traditional treatments based on implants or transplants have not proven to be completely successful, with multiple side effects such as immunogenicity or rejections. Therefore, it is very important to develop new alternatives to treat muscle degeneration. Tissue engineering combines biomaterials, cells and bioactive agents to develop biological and biocompatible constructs where cells find an in vivo likely environment to grow, proliferate and differentiate into muscle tissue and restore its functionality.
Conductive biomaterials are of particular interest in electrosensitive tissues such as the musculoskeletal system. Conductive polymers (polypyrrole, polyaniline, etc.), carbon materials (graphene, reduced graphene oxide, etc.) and metal nanomaterials have proved to enhance cell differentiation, even without external electrical stimulation. Moreover, different bioactive molecules such as growth factors (FGF-2, IGF-1, etc.) or inorganic "therapeutic" ions (zinc, magnesium, etc.) are alternatives to enhance cell differentiation into different tissues.
Therefore, the combination of conductive biomaterials and bioactive molecules to enhance muscle regeneration represents an exciting opportunity in muscle tissue engineering. This thesis project aims to develop and characterize novel electroactive biomaterials with different compositions, structures and properties and evaluate their potential to treat musculoskeletal regeneration, as well as its combination with inorganic ions looking forward to discovering new conductive biomaterial-therapeutic ions synergies in terms of muscle differentiation. / Gracias a la financiación del Ministerio de Ciencia e Innovación, a la Agencia
Estatal de Investigación y a los fondos FEDER por la financiación del proyecto RTI2018-
097862-B-C21 que ha permitido llevar a cabo esta tesis doctoral. / Aparicio Collado, JL. (2023). Development of Novel Biomimetic Electroactive Environments with Bioactive Molecules for Musculoskeletal Regeneration [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/195233 / Compendio
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Estudo da aclimatação de lodos anaeróbios como estratégia de inoculação para partida de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos / Study of the acclimation of anaerobic sludge as an inoculation strategy for star-up biomethanizers fed with organic fraction of the municipal solid wasteSimões, André Luis Gomes 21 August 2017 (has links)
A Política Nacional de Resíduos Sólidos, instituída pela Lei Federal 12.305 em agosto de 2010 e regulamentada pelo Decreto 7.404, em 23 de dezembro de 2010, estabeleceu um novo paradigma na gestão e gerenciamento dos resíduos sólidos no Brasil. Entre as mudanças apresentadas, uma das mais relevantes é a que prioriza o não aterramento da fração orgânica e a recuperação energética dos resíduos. Por esse motivo, a busca por novas tecnologias para o tratamento desses resíduos tem sido intensificada nos últimos anos. Nesse contexto, o objetivo deste trabalho busca avaliar o potencial de se realizar estratégias para aclimatação de lodos anaeróbios em possíveis inoculações de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos (FORSU). Foram analisados dois diferentes lodos, esses em função da decomposição e estabilização da FORSU por meio de ensaios de biodegradabilidade anaeróbia. O primeiro, lodo ETE (LE), foi coletado de um reator UASB, utilizado para tratamento de esgoto sanitário doméstico, já o segundo, lodo Aterro (LA), foi coletado de uma lagoa de acúmulo de lixiviados em um aterro sanitário desativado. Para os ensaios, utilizaram-se frascos Duran® de 250 mL, incubados a 35°C, considerando-se a co-digestão nas seguintes relações resíduo/inóculo (R0/I0): 1/16, 1/8, 1/4, 1/2 e 1/1 gSTVresíduo.gSTVinóculo-1. As estratégias de aclimatação consistiram em manter o inóculo para as próximas bateladas, bem como, dobrar as relações (R0/I0) com sucessivas alimentações realizadas em três bateladas sequenciais. Para que fossem possíveis o controle e a verificação do processo ao longo das bateladas, foram realizadas análises físico-químicas, microbiológicas, cinéticas e de atividade metanogênica específica (AME). Os inóculos adaptaram-se de imediato à FORSU, tendo sido verificada produção crescente de metano já nos primeiros dias dos testes. Os melhores resultados do potencial bioquímico de metano foram obtidos pelas menores relações (R0/I0) para ambos os inóculos. As maiores relações (R0/I0) influenciaram negativamente o desempenho do processo de biometanização para o inóculo LE, verificada pelas menores taxas máximas de rendimento de metano e maiores fase lag. Para o inóculo LA, ao final do processo de aclimatação foi verificado maior índice de diversidade para o Domínio Archaea, corroborando com os resultados obtidos pela quantidade de micro-organismos metanogênicos. Essas verificações se deram por meio de análises de microscopia óptica e pelos maiores valores obtidos nos testes de AME. Destarte, conclui-se que a estratégia de aclimatação se utilizando das menores relações (R0/I0): 1/16, 1/8 e 1/4 para o inóculo LA, possui o maior potencial, sendo esse na inoculação em maiores relações (R0/I0) na partida de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos, logo, garantindo-se efetividade no processo. / The National Policy on Solid Waste, instituted by Federal Law 12,305 in august 2010 and regulated by Decree 7404, on december 23, 2010, established a new paradigm in the management of solid waste in Brazil. Among the changes presented, one of the most relevant is the one that prioritizes the non-grounding of the organic fraction and the energy recovery of the waste. For this reason, the search for new technologies for the treatment of this waste has been intensified in recent years. In this context, the objective of this work is to evaluate the potential of strategies for acclimatization of anaerobic sludge in possible inoculations of biomethanizers fed with organic fraction of municipal solid waste (OFMSW). Two different sludges were analyzed, as a function of the decomposition and stabilization of OFMSW by anaerobic biodegradability tests. The first, ETE sludge (LE), was collected from a UASB reactor, used to treat domestic sanitary sewage, while the second, Aterro sludge (LA) was collected from a pond of leachate accumulation in a deactivated landfill. For the tests, 250 ml Duran® flasks incubated at 35°C were used, considering co-digestion in the following residue/inoculum ratios (R0/I0): 1/16, 1/8, 1/4, 1/2 and 1/1 gSTVresidue.gSTVinoculum-1. The acclimation strategies consisted in maintaining the inoculum for the next batch, as well as doubling the ratios (R0/I0) with successive feedings performed in three sequential batches. In order to control and verify the process throughout the batch, physical-chemical, microbiological, kinetic and specific methanogenic activity (SMA) analyzes were performed. The inocula immediately adapted to OFMSW, and there was a growing production of methane already in the first days of the tests. The best results of the biochemical potential of methane were obtained by the lower ratios (R0/I0) for both inoculum. The higher ratios (R0/I0) negatively influenced the performance of the biomethanization process for the LE inoculum, verified by the lower maximum methane yield rates and higher lag phase. For the inoculum LA, at the end of the acclimation process, a higher diversity index was verified for the Archaea Domain, corroborating with the results obtained by a number of methanogenic microorganisms. These tests were carried out by means of optical microscopy and the highest values obtained in the SMA tests. Therefore, it is concluded that the acclimation strategy using the lowest ratios (R0/I0): 1/16, 1/8 and 1/4 for the inoculum LA, has the highest potential, being inoculated at higher rates (R0/I0) at the start of biomethanizers fed with organic fraction of municipal solid waste, thus, ensuring effectiveness in the process.
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Production and characterisation of self-crosslinked chitosan-carrageenan polyelectrolyte complexesAl-Zebari, Nawar January 2017 (has links)
Macromolecular biomaterials often require covalent crosslinking to achieve adequate stability and mechanical strength for their given application. However, the use of auxiliary chemicals may be associated with long-term toxicity in the body. Oppositely-charged polyelectrolytes (PEs) have the advantage that they can self-crosslink electrostatically and those derived from marine organisms are an inexpensive alternative to glycosaminoglycans present in the extracellular matrix of human tissues. A range of different combinations of PEs and preparation conditions have been reported in the literature. However, although there has been some work on complex formation between chitosan (CS) and carrageenan (CRG), much of the work undertaken has ignored the effect of pH on the consequent physicochemical properties of self-crosslinked polyelectrolyte complex (PEC) gels, films and scaffolds. Chitosan is a positively-charged polysaccharide with NH3+ side groups derived from shrimp shells and, carrageenan is a negatively-charged polysaccharide with OSO3- side groups derived from red seaweed. These abundant polysaccharides possess advantageous properties such as biodegradability and low toxicity. However, at present, there is no clear consensus on the cell binding properties of CS and CRG or CS-CRG PEC materials. The aim of this study was to explore the properties of crosslinker-free PEC gels, solvent-cast PEC films and freeze-dried PEC scaffolds based on CS and CRG precursors for medical applications. The objective was to characterise the effect of pH of the production conditions on the physicochemical and biological properties of CS-CRG PECs. Experimental work focused on the interaction between PEs, the composition of PECs, the rheological properties of PEC gels and the mechanical properties of PEC films and scaffolds. In addition, cell and protein attachment to the PEC films was assessed to determine their interactions in a biological environment. For biomedical applications, these materials should ideally be stable when produced such that they can be processed to form either a film or a scaffold and have mechanical properties comparable to those of collagenous soft tissues. FTIR was used to confirm PEC formation. Zeta potential measurements indicated that the PECs produced at pH 2-6 had a high strength of electrostatic interaction with the highest occurring at pH 4-5. This resulted in stronger intra-crosslinking in the PEC gels which led to the formation of higher yield, solid content, viscosity and fibre content in PEC gels. The weaker interaction at pH 7-12 resulted in higher levels of CS incorporated into the complex and the formation of inter-crosslinking through entanglements between PEC units. This resulted in the production of strong and stiff PEC films and scaffolds appropriate for soft tissue implants. The PECs prepared at pH 7.4 and 9 also exhibited low swelling and mass loss, which was thought to be due to the high CS content and entanglements. From the range of samples tested, the PECs produced at pH 7.4 appeared to show the optimum combination of yield, stability and homogeneity for soft tissue implants. Biological studies were performed on CS, CRG and PECs prepared at pH 3, 5, 7.4 and 9. All of the PE and PEC films were found to be non-cytotoxic. When the response of three different cell types and a high binding affinity protein (tropoelastin) was evaluated; it was found that the CS-CRG PEC films displayed anti-adhesive properties. Based on these experimental observations and previous studies, a mechanistic model of the anti-adhesive behaviour of PEC surfaces was proposed. It was therefore concluded that the CS-CRG PECs produced might be suitable for non-biofouling applications.
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Tratamento eletrolítico de efluentes têxteis : avaliação da eficiência do processo e do potencial ecotoxicológico utilizando diferentes bioindicadores /Moraes Júnior, José Rubens. January 2019 (has links)
Orientador: Ederio Dino Bidoia / Resumo: Os efluentes têxteis têm capacidade de proporcionar cor à água de rios e lagos devido aos corantes presentes em sua composição. Além dos problemas estéticos, outros compostos presentes nestes tipos de efluentes podem ser tóxicos à vida aquática. Os processos oxidativos avançados (POA) vem sendo estudados devido a vantagem de serem mais rápidos, produzirem menos resíduos e não demandarem de grandes áreas de instalação quando se comparado a tratamentos convencionais. Este trabalho teve como objetivo a degradação de efluentes simulados contendo o corante Acid blue 40, o corante Acid red 151 e efluente misto contendo ambos os corantes por tratamento eletrolítico utilizando eletrodo de titânio recoberto por titânio/rutênio (70%TiO2/30%RuO2) com área de 40 cm² em um sistema de recirculação. Foi realizado planejamento experimental e por meio de análise de superfície de resposta, configurações de tratamentos otimizados foram realizadas. Foram realizadas análises de espectrofotometria, DQO, DBO, Cor, pH, cloro residual livre e condutividade durante os processos de tratamento. Análise de espectro de infravermelho com transformada de Fourier (FTIR) foi realizada de todos os tratamentos. Foi também verificada a geração de clorofórmio por meio de análise de cromatografia gasosa e espectrometria de massa (GC-MS). Testes de ecotoxicidade com sementes de alface (Lactuca sativa) e rúcula (Eruca sativa) e com o microcrustáceo Artemia salina foram realizados durante os tratamentos. Teste de mut... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The textile effluents have the capacity to provide color to water from rivers and lakes due to the dyes present in their composition. In addition to aesthetic problems, other compounds present in these types of effluents can be toxic to the aquatic life. The advanced oxidative processes (AOP) have been studied due to the advantage of being faster, producing less waste and not having to spend large areas of installation when compared to conventional treatments. This work aimed at the degradation of simulated textile effluents containing the Acid blue 40 dye, Acid red 151 dye and a mixed effluent containing both dyes by electrolytic treatment using a titanium electrode covered by titanium/ruthenium (70%TiO2/30%RuO2) with an area of 40 cm² in a recirculating system. Experimental design was realized by the response surface the optimized configurations of the treatments were performed. Analysis of spectrophotometry, COD, BOD, color, pH, free residual chlorine and conductivity were performed during the treatment processes. Fourier transformed infrared spectrum analysis (FTIR) were performed in all treatments. The generation of chloroform was investigated by analysis of gas chromatography and mass spectrometry (GC-MS). Ecotoxicity tests with seeds of lettuce (Lactuca sativa) and arugula (Eruca sativa) and with the microcrustacean Artemia salina were performed for during treatments. Mutagenicity test was performed using the D7 strain of the yeast Saccharomyces cerevisiae. The optimiz... (Complete abstract click electronic access below) / Doutor
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Avalia??o da biodegradabilidade de petr?leo utilizando microrganismos isolados do estu?rio do Rio Potengi (RN)Costa, C?ntia de Castro 16 August 2010 (has links)
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Previous issue date: 2010-08-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The oil activity in the Rio Grande do Norte State (RN) is a permanent threat to coastal
ecosystems, particularly mangroves, with the possibility of oil spills. In this context, the
objective of this study was to evaluate the potential resistance of the mangrove
environment of a possible spill. Were selected and isolated microorganisms degrading
oil by the technique of enrichment cultures and formation of a bacterial consortium. The
kinetic study of the consortium was held in rotary incubator shaken at 150 rpm and 30?
C. Samples were taken at intervals of 4 hours for analysis of cell concentration and
surface tension. The biodegradation was monitored using two methods of respirometry:
manometric (OxiTop-C ?) and conductivimetry, where the biodegradation of oil was
estimated indirectly by oxygen consumption and CO2 production, respectively.
Furthermore, it was used a full 2? factorial design with triplicate at central point to the
runs that used the conductivimetric methodology.. The technique of enrichment cultures
allowed to obtain thirteen bacterial strains. Kinetic study of the consortium, we can
showed the absence of the lag phase, reaching a maximum cell concentration of 2.55 g /
L at 16 h of cultivation and a reduction on surface tension. When we adopted the
methodology of OxiTop-C was detected a band indicating biodegradability (1% oil v/v),
however when we used the conductivimetry methodology did not observe any band that
would indicate effective biodegradation. By monitoring a process of biodegradation is
necessary to observe the methodology will be adopted to evaluate the biodegradation
process, since for the same conditions adopted different methodologies can produce
different results. The oil-degrading isolates from soils of the mangrove estuary Potengi /
RN are largely to be used in bioremediation strategies of these places, in the case of a
possible oil spill, or it can be used in the treatment of waste oil generated in saline
environments, since they are optimized the conditions of the tests so that the efficiency
of biodegradation reach the minimum level suggested by the standarts / A atividade petrol?fera do RN constitui uma amea?a permanente aos
ecossistemas costeiros, principalmente os manguezais, com a possibilidade de
derramamentos de ?leo. Neste contexto, o objetivo desse estudo foi avaliar o potencial
de resist?ncia do ambiente de manguezal a um poss?vel derramamento. Foram
selecionados e isolados microrganismos degradadores de petr?leo pela t?cnica de
enriquecimento de culturas e forma??o de um cons?rcio bacteriano. O estudo cin?tico
do cons?rcio foi realizado em incubador rotativo sob agita??o de 150 rpm e temperatura
de 30?C. As amostras foram retiradas em intervalos de 4h para an?lise da concentra??o
celular e tens?o superficial. A biodegrada??o foi monitorada atrav?s de dois m?todos de
respirometria: manom?trico (OxiTop-C?) e condutivimetria, nos quais a
biodegradabilidade de petr?leo foi estimada indiretamente pelo consumo de oxig?nio e
produ??o de CO2, respectivamente. Al?m disso, nos ensaios de condutivimetria foi
realizado um planejamento fatorial completo 2? com triplicata no ponto central. Pela
t?cnica de enriquecimento de culturas foram obtidas treze linhagens bacterianas. No
estudo cin?tico do cons?rcio, pode-se observar aus?ncia da fase lag atingindo-se uma
concentra??o celular m?xima de 2,55 g/L em 16 h de cultivo e queda da tens?o
superficial. Quando adotou-se a metodologia do OxiTop-C foi detectado uma faixa que
indica biodegradabilidade (1% de petr?leo v/v), no entanto quando utilizou-se a
metodologia de condutivimetria n?o foi observado nenhuma faixa que indicasse
biodegradabilidade efetiva. Ao monitorar um processo de biodegradabilidade ?
necess?rio avaliar qual a metodologia ser? adotada para avaliar o processo de
biodegrada??o, pois para as mesmas condi??es adotadas diferentes metodologias podem
apresentar resultados divergentes. Os degradadores de petr?leo isolados do solo de
mangue do estu?rio do Rio Potengi/RN podem vir a ser utilizados em estrat?gias de
biorremedia??o desses lugares, no caso de um eventual derramamento de ?leo, ou ainda,
podem ser empregados no tratamento de res?duos petrol?feros gerados em ambientes
salinos, desde que sejam otimizadas as condi??es dos ensaios de modo que as
efici?ncias de biodegrada??o atinjam o patamar m?nimo sugerido pelas normas
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Avaliação da biodegradabilidade e toxicidade de fluidos dielétricos de transformadores em solo e meio aquático / Evaluation of the biodegradability and toxicity of transformer dielectric fluids in soil and aquatic environmentSanderson, Karina 13 December 2017 (has links)
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Previous issue date: 2017-12-13 / Power distribution companies constantly contaminate the environment with dielectric fluids due to power transformer failures and leaks. In this way, these fluids should be studied, as they may entail the vulnerability of the fauna and flora. In this sense, the objective of this work was to investigate the deleterious effects of vegetal and mineral dielectric fluids, through biodegradability, acute toxicity, chemical attributes and soil degradation (oils and greases) tests as well as soybean phytotechnical characteristics evaluation. In the tests of the immediate biodegradability, vegetal dielectric fluids of crambe, W3, W6 and W9 and one based on mineral oil (Lubrax) were studied. For the acute toxicity tests with Danio rerio and Artemia salina and the soil toxicity tests using soybean (Glycine max L.), the W3 and Lubrax dielectric fluid were used. The biodegradability analysis was evaluated by the action of microorganisms that transformed the sample into CO2, being measured by titulometry. For the acute toxicity studies, two distinct experiments were performed, where the organisms were exposed to different concentrations of the W3 and Lubrax dielectric fluids and to the FSA of the fluids. The FSA of W3 and Lubrax used in the Danio rerio assay were subjected to gas chromatography analysis. The acute toxicity tests with Danio rerio and Artemia salina were carried out in order to know the approximate range of fluid toxicity, taking into account the lower dilution that caused lethality in 50% of organisms (LC50). The soil chemical attributes analyzed were: pH, P, K, Ca, Mg, CTC and V. The content of oils and greases of the dielectric fluids was quantified by the Soxhlet type extraction method. For the phytothecnical evaluations, emergence, plant height, stem diameter, root length, root dry matter, number of pods and grains, and the mass of one thousand grains were analyzed. Vegetable dielectric fluids are biodegradable over a period of 14 days, while mineral oil is difficult to biodegrade. In the acute toxicity study, W3 had a lower LC50 than Lubrax, causing higher mortality in the organisms. The LC50 for the Danio rerio was 2.46 gL-1 (Lubrax) and 0.318 gL-1 (W3). For Artemia salina the LC50 was 4.63 gL-1 (Lubrax) and 0.641 gL-1 (W3). In relation to the FSA tests, the Lubrax one caused a greater toxic effect on the organisms, while the W3 had no toxic effect on 50% of organisms. The LC50 values for Lubrax were 4.89% for the Danio rerio and 7.67% for Artemia salina. Chromatographic analysis of FSA of the fluids was not conclusive, it only suggests that the toxicity may be related to the solubility of all the substances present in Lubrax and not only to the solubility of n-alkanes. The chemical attributes of the soil did not change significantly, only the carbon presented increasing variation in relation to the concentrations of the fluids. There was a reduction of the TOG during the agricultural years and the soils in the presence of W3 presented greater degradation than those with Lubrax. The increase in the concentration of the dielectric fluids caused a reduction in the phytotechnical characteristics of the soybean. Plants from soil contaminated with W3 showed better development compared to plants that were in soil contaminated with Lubrax. / As concessionárias de energia, constantemente, contaminam o meio ambiente com fluidos dielétricos, devido a falhas e vazamentos de transformadores de potência. Desta forma, estes fluidos devem ser estudados, pois podem pode implicar na vulnerabilidade da fauna e da flora. Neste sentido, este trabalho teve como objetivo investigar os efeitos deletérios do fluido dielétrico vegetal e mineral, através de ensaios de biodegradabilidade, toxicidade aguda, ensaios dos atributos químicos e degradação (óleos e graxas) do solo e das avalições das características fitotécnicas da soja. Nos ensaios da biodegradabilidade imediata foram estudados os fluidos dielétricos vegetais de crambe, W3, W6 e W9 e um à base de óleo mineral (Lubrax). Para os ensaios de toxicidade aguda com Danio rerio e Artemia salina e para os ensaios de toxicidade em solo utilizando a soja (Glycine max L.), foram usados o fluido dielétrico W3 e o Lubrax. A análise da biodegradabilidade foi avaliada pela ação de microrganismos que transformaram a amostra em CO2, sendo medido por titulometria. Para os estudos da toxicidade aguda foram realizados dois experimentos distintos, onde os organismos foram expostos às diferentes concentrações de fluido dielétrico W3 e Lubrax e onde foram expostos à FSA dos fluidos. A FSA do W3 e Lubrax utilizado no ensaio com o Danio rerio foram submetida a análise de cromatografia gasosa. Os ensaios de toxicidade aguda com o Danio rerio e a Artemia salina foram realizados com o intuito de se conhecer a faixa aproximada de toxicidade dos fluidos, levando em consideração a menor diluição que causou letalidade em 50% dos organismos (CL50). As análises dos atributos químicos do solo foram: pH, P, K, Ca, Mg, CTC e V. O teor de óleos e graxas dos fluidos dielétricos foi quantificado pelo método de extração em aparelho tipo Soxhlet. Para as avaliações fitotécnicas da soja analisou-se a emergência, altura de planta, diâmetro do caule, comprimento radicular, matéria seca radicular, número de vagens e de grãos e a massa de mil grãos. Os fluidos dielétricos vegetais são biodegradáveis num período de 14 dias, enquanto o óleo mineral é difícil de ser biodegradado. No estudo da toxicidade aguda o W3 apresentou uma CL50 menor do que o Lubrax, causando maior mortalidade nos organismos. A CL50 para o Danio rerio foi de 2,46 gL-1 (Lubrax) e de 0,318 gL-1 (W3). Para a Artemia salina a CL50 foi de 4,63 gL-1 (Lubrax) e 0,641 gL-1 (W3). Em relação aos ensaios com a FSA, o Lubrax causou maior efeito tóxico aos organismos. O W3 não apresentou efeito tóxico a 50% dos organismos. Os valores da CL50 para o Lubrax foi de 4,89% para o Danio rerio e 7,67% Artemia salina. A análise cromatográfica da FSA dos fluidos não foi conclusiva, apenas sugere que a toxicidade pode estar relacionada com a solubilidade de todas as substâncias presentes no Lubrax e não apenas com a solubilidade dos n-alcanos. Os atributos químicos do solo não sofreram alterações significativas, apenas o carbono apresentou variação crescente em relação às concentrações dos fluidos. Houve redução do TOG durante os anos agrícolas e os solos em presença do W3 apresentaram maior degradação do que os em solos com Lubrax. O aumento da concentração dos fluidos dielétricos ocasionou redução nas características fitotécnicas da soja. As plantas em solo contaminadas com W3 apresentaram melhor desenvolvimento em relação às plantas que estavam no solo contaminado com Lubrax.
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Estudo da aclimatação de lodos anaeróbios como estratégia de inoculação para partida de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos / Study of the acclimation of anaerobic sludge as an inoculation strategy for star-up biomethanizers fed with organic fraction of the municipal solid wasteAndré Luis Gomes Simões 21 August 2017 (has links)
A Política Nacional de Resíduos Sólidos, instituída pela Lei Federal 12.305 em agosto de 2010 e regulamentada pelo Decreto 7.404, em 23 de dezembro de 2010, estabeleceu um novo paradigma na gestão e gerenciamento dos resíduos sólidos no Brasil. Entre as mudanças apresentadas, uma das mais relevantes é a que prioriza o não aterramento da fração orgânica e a recuperação energética dos resíduos. Por esse motivo, a busca por novas tecnologias para o tratamento desses resíduos tem sido intensificada nos últimos anos. Nesse contexto, o objetivo deste trabalho busca avaliar o potencial de se realizar estratégias para aclimatação de lodos anaeróbios em possíveis inoculações de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos (FORSU). Foram analisados dois diferentes lodos, esses em função da decomposição e estabilização da FORSU por meio de ensaios de biodegradabilidade anaeróbia. O primeiro, lodo ETE (LE), foi coletado de um reator UASB, utilizado para tratamento de esgoto sanitário doméstico, já o segundo, lodo Aterro (LA), foi coletado de uma lagoa de acúmulo de lixiviados em um aterro sanitário desativado. Para os ensaios, utilizaram-se frascos Duran® de 250 mL, incubados a 35°C, considerando-se a co-digestão nas seguintes relações resíduo/inóculo (R0/I0): 1/16, 1/8, 1/4, 1/2 e 1/1 gSTVresíduo.gSTVinóculo-1. As estratégias de aclimatação consistiram em manter o inóculo para as próximas bateladas, bem como, dobrar as relações (R0/I0) com sucessivas alimentações realizadas em três bateladas sequenciais. Para que fossem possíveis o controle e a verificação do processo ao longo das bateladas, foram realizadas análises físico-químicas, microbiológicas, cinéticas e de atividade metanogênica específica (AME). Os inóculos adaptaram-se de imediato à FORSU, tendo sido verificada produção crescente de metano já nos primeiros dias dos testes. Os melhores resultados do potencial bioquímico de metano foram obtidos pelas menores relações (R0/I0) para ambos os inóculos. As maiores relações (R0/I0) influenciaram negativamente o desempenho do processo de biometanização para o inóculo LE, verificada pelas menores taxas máximas de rendimento de metano e maiores fase lag. Para o inóculo LA, ao final do processo de aclimatação foi verificado maior índice de diversidade para o Domínio Archaea, corroborando com os resultados obtidos pela quantidade de micro-organismos metanogênicos. Essas verificações se deram por meio de análises de microscopia óptica e pelos maiores valores obtidos nos testes de AME. Destarte, conclui-se que a estratégia de aclimatação se utilizando das menores relações (R0/I0): 1/16, 1/8 e 1/4 para o inóculo LA, possui o maior potencial, sendo esse na inoculação em maiores relações (R0/I0) na partida de biometanizadores alimentados com fração orgânica dos resíduos sólidos urbanos, logo, garantindo-se efetividade no processo. / The National Policy on Solid Waste, instituted by Federal Law 12,305 in august 2010 and regulated by Decree 7404, on december 23, 2010, established a new paradigm in the management of solid waste in Brazil. Among the changes presented, one of the most relevant is the one that prioritizes the non-grounding of the organic fraction and the energy recovery of the waste. For this reason, the search for new technologies for the treatment of this waste has been intensified in recent years. In this context, the objective of this work is to evaluate the potential of strategies for acclimatization of anaerobic sludge in possible inoculations of biomethanizers fed with organic fraction of municipal solid waste (OFMSW). Two different sludges were analyzed, as a function of the decomposition and stabilization of OFMSW by anaerobic biodegradability tests. The first, ETE sludge (LE), was collected from a UASB reactor, used to treat domestic sanitary sewage, while the second, Aterro sludge (LA) was collected from a pond of leachate accumulation in a deactivated landfill. For the tests, 250 ml Duran® flasks incubated at 35°C were used, considering co-digestion in the following residue/inoculum ratios (R0/I0): 1/16, 1/8, 1/4, 1/2 and 1/1 gSTVresidue.gSTVinoculum-1. The acclimation strategies consisted in maintaining the inoculum for the next batch, as well as doubling the ratios (R0/I0) with successive feedings performed in three sequential batches. In order to control and verify the process throughout the batch, physical-chemical, microbiological, kinetic and specific methanogenic activity (SMA) analyzes were performed. The inocula immediately adapted to OFMSW, and there was a growing production of methane already in the first days of the tests. The best results of the biochemical potential of methane were obtained by the lower ratios (R0/I0) for both inoculum. The higher ratios (R0/I0) negatively influenced the performance of the biomethanization process for the LE inoculum, verified by the lower maximum methane yield rates and higher lag phase. For the inoculum LA, at the end of the acclimation process, a higher diversity index was verified for the Archaea Domain, corroborating with the results obtained by a number of methanogenic microorganisms. These tests were carried out by means of optical microscopy and the highest values obtained in the SMA tests. Therefore, it is concluded that the acclimation strategy using the lowest ratios (R0/I0): 1/16, 1/8 and 1/4 for the inoculum LA, has the highest potential, being inoculated at higher rates (R0/I0) at the start of biomethanizers fed with organic fraction of municipal solid waste, thus, ensuring effectiveness in the process.
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Propriétes barrière et mécaniques d'agromatériaux thermoplastiques à base de farine de blé et de polyesters biosources et biodégradables / Barrier properties of wheat flour and biobased/biodegradable polyesters based thermoplastic agro-matérials.Abdillahi, Houssein 18 April 2014 (has links)
Des produits de consommation de première nécessité aux produits les plus fortuits, l'emballage, en particulier plastique, constitue aujourd'hui un élément indispensable de notre vie quotidienne. Son utilisation intensive dans le domaine agroalimentaire pour un usage unique à courte durée de vie incite aujourd'hui à s'orienter vers de nouveaux matériaux d'origine renouvelable et biodégradables, aux caractéristiques similaires que leurs homologues issus des ressources fossiles. Les mélanges à base de biopolymères et de biopolyesters peuvent être une bonne alternative. Dans ce présent travail de thèse, des mélanges de farine de blé, thermoplastifiée par du glycérol et de l'eau, et des polyesters biosourcés et biodégradables tels que le PLA et/ou le PHB ont été obtenus par extrusion bivis et moulés par injection thermoplastique. Les caractéristiques thermiques, thermomécaniques dynamiques, morphologiques, mécaniques et barrières de ces nouveaux matériaux ont été étudiés. De l'acide citrique a été utilisé comme agent de compatibilisant pour améliorer l'interface amidon/PLA. Les différentes investigations nous ont permis de mettre au point différents types de formulations aux caractéristiques mécaniques et barrières à la vapeur d'eau intéressantes pour la fabrication de corps de barquettes d'emballage alimentaire de denrées périssables comme la viande ou les fromages. L'aptitude au contact alimentaire des matériaux farine thermoplastifiée/polyester et l'impact de l'incorporation des polyesters sur la biodégradabilité de ces matériaux ont également été étudiés. / From basic and essential to unnecessary and optional consumer products, packaging, particularly plastic, is today an indispensable part of our daily life. Its extensive use in the food industry for a single use and for a short shelf-life encourages us today to move towards new renewable and biodegradable materials with similar characteristics than their counterparts from fossil resources. Biopolymers and biopolyesters blends can be a good alternative. Within the framework of this present work, wheat flour, thermoplasticised by glycerol and water, and biobased and biodegradable polyesters such as PLA and/or PHB, were blended using an industrial twin screw extruder and were injection-molded into thermoplastic materials. Thermal, dynamic thermomechanical, morphological, mechanical and barriers properties of these new materials were studied. Citric acid was used as a compatibilizer to improve the interface starch/PLA. The different investigations have allowed us to develop various types of formulations, with mechanical characteristics and barrier properties to water vapor, very attractive for manufacturing plastic food packaging which can be used for meats or cheeses. Food contact suitability and biodegradability of thermoplasticised wheat flour/polyester materials have also studied.
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