Dissertations / Theses on the topic 'Polymers Recycling'
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Guo, Haochen. "RECYCLING THERMOPLASTIC EVA (POLYETHYLENE-CO-VINYL ACETATE) WITH IMPROVED PROPERTIES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1585673886043802.
Full textParpart, Dawn Allison. "PET/nylon 66 polymer blends and carpet recycling." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/9139.
Full textWong, Joseph Man 1959. "A nonplugging annulus control valve for extrusion of polymers and slurries." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276855.
Full textRuiz, Ilza Aparecida dos Santos. "Adição de EPDM ou anidrido maléico na blenda LDPE/PA6 e suas propriedades finais." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-11052009-133033/.
Full textIn virtue of the increasing volume of the multilayers packings use in the food preservation, the study for the recycling of these materials through its reverse speed-exploitation as raw material and the transformation in new products or materials becomes necessary. Amongst some types of recycling used currently, the polymers blendes formation with discarded material is presented as a viable alternative, therefore if it deals with a modern activity that joins the technological development and the ambient preservation. The present research, therefore makes a study on the recycling of residues from multilayers packings after-consumes in the nourishing sector for the blend formation. The multilayer film composed by polyamide 6 and polyethylene of low density was previously worn out for flake attainment and it was added first the Ethylene-Propylene-Diene-Monomer (EPDM) additive and after that a new composed maleic anhydride mixture was made only with multilayer film in the flake form, in intention to improve the mechanical properties of blendes formed for the process of the drawing. For verification of the results assays had been carried through traction tests, rupture lengthening tests and permeability to the gas oxygen in the film of polyamide 6 and mechanical properties of blendes formed for the process of the drawing. For verification of the results assays had been carried through traction tests, rupture lengthening tests and permeability to the gas oxygen in the film of polyamide 6 and mechanical polyethylene, and assays, thermal analyses and scanning electronic microscopy in the blendes. It was also studied radiation dose (100 kGy) on the blends properties using an electron beam accelerator.
Granowski, Gregory A. "Recycling of PVC and XLPE for High Impact Resistance in Spool Development." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157640/.
Full textMohammadzadeh, Maryam. "Characterization of recycled thermoplastic polymers." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19650.
Full textWei, Ren, and Wolfgang Zimmermann. "Biocatalysis as a green route for recycling the recalcitrant plastic polyethylene terephthalate." Universität Leipzig, 2017. https://ul.qucosa.de/id/qucosa%3A21102.
Full textSOUZA, ELISEU W. de. "Estudo para fabricacao de refletores automobilisticos utilizando um material composito termofixo de um material termoplastico." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9602.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Sommer, William J. "Supported catalysts, from polymers to gold nanoparticles supports." Diss., Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-07062007-225935/.
Full textChristoph J. Fahrni, Committee Member ; Mostapha A. El-Sayed, Committee Member ; Christopher W. Jones, Committee Member ; Marcus Weck, Committee Chair ; E. Kent Barefield, Committee Member.
ROSSINI, EDVALDO L. "Obtencao da blenda polimerica PET/PP/PE/EVA a partir de 'garrafas PET' e estudo das modificacoes provocadas pela radiacao ionizante." reponame:Repositório Institucional do IPEN, 2005. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11373.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Duru, C. Zeynep. "Effect Of Rigid Rod Molecular Structures On The Properties Of Regenerated And Virgin Polyethyleneterephtalate." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605444/index.pdf.
Full textXie, Wa. "Surface Topography and Aesthetics of Recycled Cross-Linked Polyethylene Wire and Cable Coatings." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc799512/.
Full textQuitadamo, Alessia. "Influence of wood flour and cellulose on the properties and the stability of formulations based on polyolefins and bio-based polymers." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI015.
Full textThe objective of this research is the development of high-added value materials, with high amount of bio-derived fillers, resulting in a more eco-friendly product. The pursued strategy is based on both the introduction of natural fibres and the use of oil-based and bio-derived polymer blends as matrices, reducing the non-biodegradable amount in the material. The thesis project is based on the development of HDPE/PLA blends filled with natural fillers, such as wood flour and recycled paper fibres. High-density polyethylene has been chosen because it is one of the most representative recycled polymers on the market. Poly(lactic) acid has been selected as it is an important bio-degradable polymer on the market. The methodology developed here can be extended to other bio-degradable polymers, such as Soy Protein Isolate (SPI). Wood flour is a diffuse waste material, that can be used for production of Wood Plastic Composites. Recycled paper fibres are derived from industrial paper waste, which cannot be subjected to traditional recycling processes. Additives have been introduced in order to face the problem of different hydrophilicity between oil-based/bio-derived polymers with natural fillers. The optimal composition and production processes are challenges, not only for the use of these materials, but also for their disposal. The end-of-life of these samples can be evaluated through controlled bio-degradability and compostability, correlating material structure with the ability to biodegrade. The production of a material at reduced environmental impact with properties consistent with their applications is a first environmental advantage. Obtaining a controlled biodegradability, as a function of the applications, would give enhanced value to our materials. Several characterizations have been performed in order to analyse the effect of different compatibilizers and treatments such as: tensile tests, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analyses, infrared spectroscopy, size exclusion chromatography and composting tests
Freitas, Dayane Taylor de. "Estudo da separação triboeletrostática de resíduos poliméricos pósconsumo e determinação do limite de contaminação entre PET e PEAD." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/97/97134/tde-04122018-141312/.
Full textThe use of polymers has increased significantly in several industrial sectors, replacing materials such as wood, metals, glass, etc. However, the constant generation of plastic wastes and their disposal generate environmental problems, because most of them are disposed to landfill. Thus, polymer recycling seems to be the most economical and environmentally friend alternative, since it contributes to minimize the consumption of non-renewable resources, as petroleum, also reducing the toxic gases emission generated during the production and decomposition processes. The polymer separation in their different types is one of the most important stages of the recycling process, because due to the diferences in their chemical and physical properties, when they are mixed and processed, low quality products are produced. In Brazil, manual separation is the most used method, but it presents great disadvantages, due to the unheathy conditions that the workers are subjected to and the possibility of human errors during the process. The aim of this work was to study different polymer separation methods, emphasizing the triboelectrostatic separation, besides determining contamination limits between polyterephthalate ethylene (PET) and high density polyethylene (HDPE) in the final recycled product. A device for triboelectrostatic separation of polymers was developed, which was effective in the separation of polyvinyl chloride (PVC) / PET, PVC / acrylonitrile-butadiene-styrene (ABS) and ABS / HDPE blends, reaching percentages of recovery greater than 80% and purity above 90%. Contamination between PET and HDPE was evaluated, based on the morphology and mechanical properties presented by the blends prepared. The limit of 3% of PET contamination in the HDPE was determined, but it was not possible to determine the limit for the contamination of HDPE in PET, because even in small concentrations of the contaminant, the blends presented unstable behavior in the mechanical tests performed, due to the morphological characteristics of the blends produced.
Ma, Nini. "Direct Force Measurement between Surfaces Coated with Hydrophobic Polymers in Aqueous Solutions and the Separation of Mixed Plastics by Flotation." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/36399.
Full textWhile water contact angle is the most widely used measure of the hydrophobicity of a solid, it does not give the information on the kinetics of flotation. Therefore, the forces acting between the surfaces coated with different hydrophobic polymers (or plastics) in water were measured using the Atomic Force Microscope (AFM). The results obtained with polystyrene, polymethylmethacryrate (PMMA), polypropylene (PP), and Teflon showed the existence of long-range attractive forces (or hydrophobic force) that cannot be explained by the classical DLVO theory. The surface force measurements were conducted in pure water and in solutions of surfactant (alkyltrimethylammonium chloride) and a salt (NaCl). In pure water, the attractive forces were much stronger than van der Waals force. In the presence of the surfactant and NaCl, the long-range attraction decreased with increasing concentration and the alkyl chain length.
A series of contact angle measurements were conducted to determine the hydrophobicity of polystyrene (PS), polyvinyl chlorite (PVC), and polymethylmethacrylate (PMMA) in the presence of different wetting agents (surfactants). The results show the possibility of separating plastics from each other by flotation, and a series of microflotation tests conducted on PS and PVC showed promising results.
Master of Science
Silva, Fabio Nascimento da. "Estudo da pirolise de poliamida-12 em leito fluidizado borbulhante." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264085.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: O objetivo do presente trabalho consiste em avaliar a degradação térmica de poliamida-12 obtida como resíduo de processos de prototipagem rápida por via pirolítica para obtenção de produtos líquidos e gasosos que possam ser usados como insumos e para a geração de energia em indústrias. Foram utilizadas diferentes configurações no leito fluidizado, alterando parâmetros de temperatura, velocidade de fluidização e altura do leito de inerte. A poliamida-12 é utilizada em máquinas de prototipagem rápida para confecção de moldes e peças. Após cerca de 250 horas de utilização, o material perde suas características originais sendo, então, descartado. O descarte da poliamida é feito armazenando o material em tambores até que seja elaborada uma solução alternativa. O estudo da pirólise de poliamida-12 apontou que o material é convertido em gás e produto líquido, não sendo gerado resíduo sólido após o processo. O gás gerado possui concentrações consideráveis de H2 e N2. Foi demonstrado que baixas velocidades de fluidização e elevadas temperaturas favorecem a formação de gás, contudo, a altura do leito fixo não influenciou de maneira significativa os resultados. O estudo comprova a aplicabilidade da reciclagem de PA-12 por processos de pirólise, gerando basicamente gás de síntese. Palavras Chave: Poliamida-12, pirólise, reciclagem, pirólise de polímeros
Abstract: The aim of this work is to evaluate the thermal degradation by pyrolysis of polyamide-12 obtained as residue from rapid prototyping processes for generation of liquids and gaseous products that should be used as supplies and to energy generation on industries. Were utilized different bed's configurations, changing parameters as temperature, fluidization air speed and inert bed's height. The polyamide-12 is utilized in rapid prototyping machines for the confection of moulds and pieces. After about 250 hours of utilization, the material loses it original characteristics and it is discarded. The discard of used polyamide has been done by saving the material in gallons until another way be elaborated. The study of pyrolysis of polyamide-12 shown the material conversion into gas and liquid product, without production of solid waste after the process. The gas has considerable concentrations of H2 and N2. It was demonstrated that low fluidized gas speed and high temperatures increases the gas formation, however, the fixed bed height did not have several influence in the results. This study confirms the applicability of PA-12 recycling by pyrolysis processes, generating synthesis gas. Key Words: Polyamide-12, pyrolysis, recycling, polymers pyrolysis
Mestrado
Termica e Fluidos
Mestre em Engenharia Mecânica
Luckmann, Luciano. "Reciclagem de resíduo de espuma rígida de poliuretano através da incorporação de polímeros termoplásticos, ABS, PSAI e OS." Universidade do Estado de Santa Catarina, 2005. http://tede.udesc.br/handle/handle/1739.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
Nowadays, the refrigeration industry uses the rigid polyurethane foam (PUR) as a thermal insulation and structural component in doors and cabinets of refrigerators and freezers. The waste of PUR generated in the manufacturing represents great volumes, which are considered an environmental problem. Some attempts of recycling this material have already been explored, such as the use in the manufacturing of bricks, roofing tiles, vases; lining confection with isolating properties; in the civil construction, etc... This work presents an alternative for the recycling of rigid polyurethane foam. A study of the incorporation of rigid polyurethane foam residues in thermoplastic matrices of Polystyrene (PS), High Impact Polystyrene (HIPS) and Acrylonitrile-butadiene-styrene copolymer (ABS) was done. The PUR waste was prepared through the milling of the material. The incorporation of PUR in PS, HIPS and ABS was realized through the extrusion of the materials in different mass concentrations. The laboratorial tests were carried through in agreement with standard norms ASTM D1238 (Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion) and D638 (Standard Test Method for Tensile Properties of Plastics). The increasing of PUR concentration over the mix with the three termoplastic matrices decreases the Melt Flow Rates of the mixtures. It was showed the possibility to know a thermoplastic polymer viscosity through Melt Flow Tests. Also mechanical properties determination and comparison through tensile test analysis have been carried through: maximum tension and tension of rupture, deformation at the elastic limit and at the rupture and determination of Young´s modulus in function of the mass concentration of PUR in the thermoplastic matrixes.
Atualmente, a indústria de refrigeração utiliza a espuma rígida de poliuretano (PUR) como isolante térmico e componentes estrutural em portas e gabinetes de refrigeradores e freezeres . Grandes volumes de rejeitos da espumas de PUR são gerados na indústria, os quais representam um problema ambiental. A destinação deste resíduo normalmente acontece por meio da desposição em aterro industrial, gerando custos adicionais à indústria, os quais não agregam volores aos seus produtos finais. Algumas tentativas de aproveitamento deste material estão sendo estudadas, tais como utilização na fábrica de tijolos, telhas, vasos; confeção de placas de forro com propriedades isolante; na construção de lajes, etc... O presente trabalho apresenta uma alternativa na reciclagem de espuma rígida de poliuretano. Foi realizado um estudo de incorporação de resíduo de espuma rígida de poliuretano, preparados a partir da moagem do material, em matriz termoplástica de poliestireno (PS), poliestireno de alto impacto (PSAI) e copolímero de acrilonitrila, butadieno e estireno (ABS). A incorporação do PUR em PS, PSAI e ABS foi realizada através da extrusão dos materiais em concentrações mássicas diferentes. Foi possível a incorporação de PUR nas resinas termoplástica até uma concentração de 0,40 g/g. Os testes laboratoriais foram realizado conforme normas ASTM D1238 (Determinação do Índice de Fuidez IF) e D638 (Ensaio de Tração). De uma forma geral, o aumento da concentração de PUR nas misturas com três matrizes termoplásticas reduz a fluidez da respectivas misturas. Foi demonstrada a possibilidade de determinar a viscosidade de um polímero termoplástico a partir de ensaios de Índice de Fuidez, os quais possibilitaram a determinação de segmentos das curvas reológicas das misturas estudadas. Também foram realizadas a determinação e a comparação das propriedades mecânicas através de ensaio de tração: tensão máxima e de ruptura, deformação no limite elástico e na ruptura e determinação do módulo de elasticidade em função da concentração mássica de PUR na matriz termoplástica.
ISOLDI, ANA B. G. "Estudo do efeito da dose de radioesterilizacao sobre as propriedades do poli(tereftalato de etileno) - PET reciclado." reponame:Repositório Institucional do IPEN, 2003. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11134.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Panek, Joel C. "Fragmentation of brittle polymeric toner line caused by swelling of paper substrate during immersion in water." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/5808.
Full textMARTIN, SANDRA R. S. "Recuperação/reciclagem de compostos de borrachas butílica e halobutílica por meio de radiação ionizante." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10549.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Cabrera, Alvino Géraldine. "Eco-design and processing of recycled multilayer/multiphase polymer materials : Structure-properties-process relationship." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI076.
Full textIn the context of a circular economy, the first works of the thesis were devoted to the study of the processing ability of recycled flexible films from agricultural bale wrapping film's waste. These multilayer films initially contain an additive that gives the final product a sticky character. During recycling, this additive is still present and migrates to the surface. A particular emphasis has been placed on understanding and studying the migration mechanisms of this additive according to the molecular architecture of the polyethylenes used with different branching content. Model blends, with or without mineral fillers, were prepared for this purpose. In addition to morphological and microstructural studies, original experimental methodologies have been set up to study the migration/diffusion kinetics with tribo-rheometry and film surface's "tack" monitoring devices. As for the rheological behaviour in shear and elongation, it is influenced by the presence of this additive. The second part of this study was devoted to understanding the realities of the recycling activity of other polypropylene- and polyethylene-based multilayer films. Given the complexity of these materials, we chose to study equivalent model blends by combining them with physical compatibilizers. The influence of the latter on the rheological, morphological and mechanical properties was then evaluated. This study was then transposed to postconsumption multiphase systems. The last studies were devoted to a future-oriented approach. This involves going from eco-design to the development of easily recyclable multimicro/ nanolayers. The originality of this study consists in limiting the number of constituents, reducing/controlling the thickness of the layers and avoiding the use of tie-layers. Finally, their rheological, morphological and mechanical properties have been evaluated according to number and type of mechanical recycling cycles
Stefanelli, Talita Katiuska Takizawa Dias 1983. "Remoção de corante de poli(tereftalato de etileno) (PET) através de recristalização e sua posterior despolimerização em meio ácido." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266615.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O consumo de polímeros sintéticos no Brasil e no mundo vem aumentando há décadas, numa clara demonstração do enorme sucesso conseguido por esses materiais nas mais variadas aplicações. As características típicas dos polímeros sintéticos, como seu custo praticamente irrisório, baixo peso, boa resistência mecânica, impermeabilidade, transparência e capacidade de coloração mais impressão lhe conferiram trunfos irresistíveis para seu uso massivo na forma de embalagens, uma aplicação extremamente importante numa sociedade voltada para o consumo. O grande problema dos polímeros sintéticos reside na sua curta vida útil, o que conduz a um rápido aumento da corrente de resíduos, como é o caso das embalagens. Dentro desse âmbito, a reciclagem passa ser uma alternativa promissora. Por definição, a reciclagem é um processo de transformação dos materiais previamente separados para posterior utilização; é a recuperação de resíduos mediante uma série de operações que permitem que materiais processados sejam aproveitados como matéria-prima no processo gerador ou em outros. A primeira etapa deste trabalho foi a tentativa de fazer a despolimerização de PET utilizando o processo de destilação molecular. Os resultados mostraram que não é possível utilizar o destilador molecular na despolimerização do PET. Na segunda etapa deste trabalho o pet pósconsumo foi submetido à recristalização para remoção do corante, utilizando ácido trifluoracético como solvente, na tentativa de uma nova alternativa de reciclagem para este material. O material modificado e o PET pós-consumo foram caracterizados por termogravimetria (TG) e calorimetria exploratória diferencial (DSC)
Abstract: The use of synthetic polymers in the world and particularly in Brazil has been increasing for decades representing the huge success achieved by these materials in various applications. The main characteristics of synthetic polymers are their low cost and weight, good mechanical strength, impermeability, transparency and the possibility of coloring, which results in their massive use in the form of packaging an application extremely important in a society focused on consumption. Despite all its advantages, the polymers are generally used in the manufacture of objects whose useful life it is extremely short, like bottled water and soft drinks , produced with polyethylene terephthalate (PET), or as previously mentioned, in packs of all species, resulting in a rapid increase in the waste stream. In this scenario, recycling becomes a promising alternative. By definition, recycling is a process of transformation materials previously separated for later use or is the recovery of waste by means of a series of operations that allow processed materials to be utilized as raw material in generating process or in other process. The first stage of this work was to attempt to make the depolymerization of PET using molecular distillation process, but results showed that it is not possible to use the molecular distiller for the depolymerization of this type of polymer. In the second stage of the work, post-consumer PET was subjected to recrystallization to remove the dye, using trifluoroacetic acid as solvent in in a new attempt to recycle this material. The modified material and post-consumer PET were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)
Mestrado
Desenvolvimento de Processos Químicos
Mestra em Engenharia Química
Solouki, Bonab Vahab. "Polyurethane (PU) Nanocomposites; Interplay of Composition, Morphology, and Properties." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1542634359353501.
Full textChikh, Amirouche. "Étude des mélanges PHBV/PBS et des mélanges hybrides PHBV/PBS/sépiolite : préparation, caractérisation physico-mécanique et durabilité." Thesis, Lorient, 2018. http://www.theses.fr/2018LORIS496/document.
Full textThe main objective of this work was to study the structure-properties relationships of biopolymerblends based on poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polybutylene succinate (PBS). The work was devised into three parts. The first part was devoted to the study of the properties of PHBV/PBS blends prepared by melt compounding at different weight ratio in terms of morphology and properties. The results obtained were discussed in terms of properties and compared with the neat polymers. The second part was devoted to the study of compatibility of PHBV/PBS blends aiming to improve the interactions at the interface between the two components. The effects of both sepiolite (5% wt.) and PHBV-g-MA (5% wt.) were studied in terms of properties. The results showed a synergistic effect between the compatibilizer PHBV-g-MA and the nanofiller sepiolite though an increase in thermal, mechanical and rheological properties. The last part dealing with the recyclability of PHBV/PBS through the study of the effects of repeated extrusion cycles on the properties of materials. The results showed that after 6 reprocessing cycles the thermo-mechanical degradation of PHBV is significantly reduced in the presence of PBS
Huynh, Anh Nhut Materials Science & Engineering Faculty of Science UNSW. "Rubber-polymer blends: a thesis in polymer engineering." Awarded by:University of New South Wales. Materials Science & Engineering, 2007. http://handle.unsw.edu.au/1959.4/40833.
Full textKIYAN, LUDMILA de Y. P. "Aplicação da radiação gama para incorporação do pó de borracha em formulações de borracha EPDM e nitrílica." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23177.
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Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Scopel, Bianca Santinon. "Obtenção e caracterização de filmes poliméricos a partir de amido de milho e de gelatina recuperada de resíduos de couro curtido ao cromo (III)." reponame:Repositório Institucional da UCS, 2016. https://repositorio.ucs.br/handle/11338/1173.
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Signoret, Charles. "Valorisation de Matières Premières Secondaires (MPS) thermoplastiques en mélange issues de tri spectroscopique en ligne - Projet Mélanie MIR spectral characterization of plastic to enable discrimination in an industrial recycling context: I. Specific case of styrenic polymers MIR spectral characterization of plastic to enable discrimination in an industrial recycling context: II. Specific case of polyolefins." Thesis, IMT Mines Alès, 2019. http://www.theses.fr/2019EMAL0005.
Full textPhD works presented here were performed within the context of mechanical recycling of polymers recovered from WEEE (Waste Electrical and Electronic Equipment), mainly represented by styrenic polymers (HIPS and ABS). A first part focused on polymer discrimination thanks to Fourier-Transform Infrared spectroscopy (FTIR), the static equivalent of MIR-HSI (Mid-Infrared Hyperspectral Imagery) which could represent an answer to the technological obstacle of dark colored plastics sorting. About forty references of virgin polymers (some of them aged in laboratory), mineral fillers and flame retardants were compared to real WEEE waste stocks to establish an identification methodology, to highlight possible confusions and emphasize key signals.Recyclability of ABS and HIPS was studied by extruding model samples aged in both natural and artificial conditions at different durations. Strong discolorations monitored by photometry, exclusively for previously photooxydized materials, showed a strong reactivity during extrusion from species formed during ageing. Mechanical properties, including static ones through tensile tests, dynamic ones in instrumented impact and melted state rheology, showed, for some of them, an interaction between the two degradation phenomena.The last aspect of these works concerned the management of post-sorting residual PP impurities within ABS. With model systems, it was observed that impact properties began to fall at 2w% of impurities to reach a minimum at 4w%. Compatibilization trials lead to the selection of PP-g-MA and SEBS as interesting compatibilizers. Predictive modeling of static behavior towards failure, based on morphological analysis of polymer blends (SEM and AFM) and photomecanically instrumented tensile tests, highlighted the sensitivity of break properties to the distribution of PP nodules sizes under the influence of a compatibilize
Kianbakhsh, Pejman. "Recycling polymer composite hydrogen pressure vessels." Thesis, University of Nottingham, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546472.
Full textJalilian, Mohammadali. "Impact of MXD6 on the Structure and Properties of Mechanically Recycled PET Blends." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1513354154142392.
Full textŻuk, Tomasz. "Separacja elektrostatyczna mieszanin tworzyw biodegradowalnych." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2015. http://dlibra.utp.edu.pl/Content/850.
Full textVoytyuk, Nazariy. "Recycling of Polypropylene and Polyamide Blends Using Thermomechanical Recycling." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277883.
Full textSyftet med avhandlingen var att återvinna en vanlig matta som innehåller polyamid-6- och polypropenpolymerer med termomekanisk återvinning och jämföra produkten med rena polymermaterial. Det återvunna materialet tillverkades med den termomekaniska processen som inkluderar malning och strängsprutning (extrudering). Filamentet analyseras med olika analystekniker inklusive FTIR, SEM, DSC och dragprovning för mekaniska egenskaper. Filamentet testas sedan med en 3D-skrivare för att se om en produkt kan tillverkas av materialet. Filamentet med återvunnen matta användes för att skapa en 3D-skriven produkt, därför verkar metoden lovande. Resultaten från analysteknikerna visade polymererna bröts ner efter flera återvinningscykler, mestadels av PA6-polymeren. De mekaniska egenskaperna med tillsats av återvunnet matta till en blandning av rena material visar liknande egenskaper jämfört med endast rena material. Sammanfattningsvis är det möjligt att 3D-skriva med återvunnet mattfilament för att skapa en 3D-skriven produkt, metoden verkar lovande.
Karunarathna, Mudugamuwe Hewawasam Jayan Savinda. "Photochemistry of iron(III) with carboxylate-containing polysaccharides for sustainable materials." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1586468303760847.
Full textCalgaro, Camila Ottonelli. "AVALIAÇÃO DA APLICAÇÃO DE CO2 SUPERCRÍTICO NA PRESENÇA DE COSOLVENTES PARA A RECICLAGEM DE PLACAS DE CIRCUITO IMPRESSO DE CELULARES." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/7994.
Full textTechnological development and intensive marketing support the growth of demand for electrical and electronic equipment (EEE), which have as a primary component printed circuit boards (PCBs). These devices have become obsolete in a shorter period of time, then residual PCBs become a problem, requiring recycling. The PCBs are composed of ceramic, polymers and metals, especially copper, metal present in the highest percentage. In addition they contain toxic substances such as brominated flame retardants and heavy metals. So the PCBs represent a problem and an opportunity at the same time, they require proper treatment and they are composed for materials with economic value. Therefore the aim of this study was to evaluate the application of supercritical CO2 and co-solvents in the recovery of copper and polymers from mobile phone PCBs, for the development of a more efficient and environmentally friendly recycling process. The study involved the mechanical processing of PCBs separated from discarded mobile phones; the characterization of PCBs; copper recovery using the CO2 supercritical leaching and H2O2 and H2SO4 as cosolvents, this method was conducted comparatively with leaching at atmospheric pressure using H2O2 and H2SO4 as leaching agents; Electrowinning of copper supercritical leached; and recovering the polymer fraction contained in the PCBs, using ethanol as cosolvent. The results indicated that mechanical processing in two milling, carried out in a hammer mill and knives mill were important for the reduction of PCBs to particle diameter less than 2 mm. From the leaching with aqua regia, it was determined that the PCBs containing 34.83 wt% copper. The characterization steps have demonstrated that PCBs are composed of 64.02% of metal, 20.51% of ceramics and 15.47% of polymers. The results showed that the supercritical leaching is 9 times faster than the atmospheric leaching. About 90% of copper was extracted from PCBs in 20 min of supercritical leaching, employing a solid:liquid ratio of 1:20, 20% (v/v) H2O2 and H2SO4 (2.5M). From the electrowinning, performed in a current density of 250 A / m², the copper metal form was recovered with 95.97% purity, reaching a current efficiency of 99%. It was extracted 69.53% of the polymers present in the PCBs using supercritical CO2 and ethanol co-solvent at 170 ° C and 7.5 MPa. Therefore the application of supercritical CO2 and co-solvents is a promising method and efficient to PCBs recycling.
O desenvolvimento tecnológico e marketing intenso propiciam o crescimento da demanda por equipamentos elétricos e eletrônicos (EEE), os quais apresentam como componente primário as placas de circuito impresso (PCIs). Como esses equipamentos vêm se tornando obsoletos em um menor intervalo de tempo, as PCIs residuais tornam-se um problema, necessitando de reciclagem. As PCIs são compostas por cerâmicos, polímeros e metais, com destaque para o cobre, metal presente em maior percentual, além de conterem substâncias tóxicas como os retardantes de chama bromados e os metais pesados. De modo que as PCIs representam um problema e uma oportunidade ao mesmo tempo, pois requerem tratamento adequado e são compostas por materiais com valor econômico agregado. Diante disso, o objetivo deste trabalho foi avaliar a aplicação de CO2 supercrítico na presença de cosolventes para a recuperação do cobre e na remoção dos polímeros de PCIs de celulares, visando o desenvolvimento de um processo de reciclagem mais eficiente e ambientalmente aceitável. O estudo compreendeu o processamento mecânico das PCIs separadas manualmente de celulares descartados; a caracterização das PCIs; a recuperação do cobre a partir da lixiviação com CO2 supercrítico e H2O2 e H2SO4 como cosolventes, realizada de forma comparativa com a lixiviação à pressão atmosférica utilizando H2O2 e H2SO4 como agentes lixiviantes; a eletro-obtenção do cobre lixiviado supercriticamente; e a recuperação da fração polimérica contida nas PCIs, empregando etanol como cosolvente. Os resultados obtidos no processamento mecânico indicaram que as duas moagens, realizadas em moinho de martelos, seguido de facas, foram importantes para a redução das PCIs a partículas de diâmetro inferior a 2 mm. A partir das lixiviações com água régia, determinou-se que as PCIs contêm 34,83% em massa de cobre. As etapas de caracterização demonstraram que as PCIs são compostas por 64,02% de metais, 20,51% de cerâmicos e 15,47% de polímeros. Os resultados mostraram que a lixivação supercrítica é 9 vezes mais rápida do que a lixiviação à pressão atmosférica. Extraiu-se, em 20 minutos de lixiviação supercrítica, cerca de 90% do cobre contido nas PCIs, empregando uma razão sólido:líquido de 1:20, 20% (v/v) de H2O2 e H2SO4 (2,5M). A partir da eletro-obtenção, realizada em uma densidade de corrente de 250 A/m², recuperou-se o cobre na forma de depósito metálico com 95,97% de pureza, alcançando uma eficiência de corrente de 99%. Extraiu-se 69,53% dos polímeros presentes nas PCIs, a partir de CO2 supercrítico modificado com etanol, a 170°C e 7,5 MPa. Portanto a aplicação de CO2 supercrítico na presença de cosolventes é um método promissor e eficiente à reciclagem das PCIs.
Gripon, Layla. "Contribution au recyclage et à la valorisation des matières plastiques issues des déchets d’équipements électriques et électroniques contenant des retardateurs de flamme bromés." Thesis, Ecole nationale supérieure Mines-Télécom Lille Douai, 2020. http://www.theses.fr/2020MTLD0014.
Full textBrominated flame retardants (BFR) are added to polymers to enhance their flammability resistance. But some of them are nowadays considered as persistent organic pollutants (POP). To avoid their propagation into recycling streams, plastic materials which bromine concentration is too high (> 2000 ppm) are generally incinerated to destroy the pollutants they contain. The objective of this work is to find a solution to recycle BFR containing plastics materials while respecting the regulations. The study is focused on an acrylonitrile-butadiene-styrene (ABS) batch coming from real waste electrical and electronic equipment which contains a POP concentration about four times higher than the regulation limit authorizing recycling. Physico-chemical methods were studied to extract BFR. Solid-liquid extractions with stirring and diethyl ether as well as the dissolution-precipitation method lowered the POP concentration under the regulatory limit. A detailed study on supercritical CO2 extraction was performed and showed its efficiency to remove BFR, but optimizations are still needed. The recycling environmental impacts were also evaluated considering the pre-treatment processes studied previously. The energy and solvent consumptions need to be optimized in order to make the recycling process more viable compared to incineration. The treated plastic material showed that it can be easily recycled. Nevertheless, its impact strength could be improved during a formulation step. Finally, a practical application of this material in a bilayer structure was proposed to enhance its mechanical and esthetic properties. Good adhesions were obtained with virgin ABS and ABS/PC materials guaranteeing satisfactory properties to the bilayer structure
Twite, Kabamba Eddy. "Polymer foams and composites recycling : Rheological and Macromolecular Investigations." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27578/27578.pdf.
Full textPei, Haohong [Verfasser]. "RNA Polymerase Recycling in Bacillus subtilis / Haohong Pei." Berlin : Freie Universität Berlin, 2021. http://d-nb.info/1234451530/34.
Full textSelvakumar, Pitchaivelu. "Characterisation of aqueous two phase partition systems by distribution analysis of radiolabeled analytes : application to process definition and control in biorecovery." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251886.
Full textCruz, Sanchez Fabio Alberto. "Methodological proposition to evaluate polymer recycling in open-source additive manufacturing contexts." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0291/document.
Full textSince the beginning of the XXI century, we can recognize that several technical (r)evolutions have changed the way we conceived our world. New realities have appeared thanks to the information and communication technologies (e.g. Internet), peer-to-peer dynamics (e.g. open software/hardware, collaborative economy), new means of production (fablabs, hackerspaces), among others. One of the impacts of this technical ecosystem is the individual's empowerment that changes the relationship between consumer and producer. For instance, we observe an evolution of role passing from a passive consumer towards an active prosumer, where this latter considers not only economic aspects, but also social and environmental issues.This thesis is integrated in this global issue; indeed, throughout the manuscript we analyze about the impact of open-source (OS) Additive Manufacturing (AM) (also as known as open-source 3D printing or just 3D printing) in the light of the sustainability issues. The democratization of OS AM and the creation of spaces for co-creation (e.g. FabLabs) proved the interest for changes in the established roles. Therefore, we are interested in how this OS technology could develop sustainable waste management options through a polymer recycling process. In a first phase, we present the concept of additive manufacturing (AM) and its importance on sustainability issues. A systematic literature review related to the material recycling advances in the commercial and open-source (OS) AM is developed with a focus on thermoplastic polymer recycling.In a second phase, our aim is to validate open-source AM systems as a reliable manufacturing tool. We develop and test an experimental protocol in order to evaluate the dimensional performance using as case study a representative OS 3D printer: called FoldaRap. It was found that the International Standard Tolerance Grade of this machine is situated between IT14 and IT16. We conclude that the dimensional performance of this case study is comparable to the commercial AM systems, taking into account the important different in terms of machine cost. In a third phase, we center our attention on the recycling process and we propose a systematic methodology to evaluate the feasibility of the use of recycled thermoplastic polymer in OS 3D printers. A case study is developed with the evaluation of the recycling process using polylactid acid (PLA). The results allow us to conclude that the use of recycled PLA is technically feasible. Nevertheless, the degradation of the material is more important than in other traditional manufacturing systems (e.g. injection). Finally, we concludes and propose as perspectives, the study of a distributed recycling process for other type of polymers
Liang, Tian. "Continuous Devulcanization of Ground Tire Rubber of Different Particle Sizes Using an Ultrasonic Twin-Screw Extruder." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1366063285.
Full textHöög, Carl. "PET Recycling – Material and Performance aspects." Thesis, KTH, Fiber- och polymerteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293044.
Full textThe recycling and collection of PET bottles has a long tradition in Sweden dating back to 1994 and is one of the staple recycling industries.Technology has advanced since then, with new recycling processes to assure food grade certified recycled PET and manufacturing processes such as Solid-State polymerization to enable the bottle-to-bottle mantra. Amidst global warming and climate crisis, the interest in recycling and reducing the use of fossil fuel to manufacture new bottles is ever-growing. As a result, manufacturers and breweries want bottles manufactured with higher fractions of recycled PET, and there are already bottles out on the market made from 100% recycled PET. In this thesis, the effect that the fraction of recycled PET may have on the mechanical and chemical properties of the final product was tested. Also, the effect that several recycling cycles may have on the product was tested.A lab-scale version of the recycling process used commercially in Sweden by Veolia PET were carried out. Four cycles of the process were carried out on virgin PET material, resulting in material batches krPET-1 to krPET-4. Dog bone samples from each recycled batch were manufactured via injection moulding with 25, 50 and 100% rPET fractions. All samples were characterized with various instruments and methods such as FT-IR, Tensile testing, DSC, and intrinsic viscosity testing.From an environmental standpoint, there are clear advantages to an increase in rPET fraction in PET-bottles. Due to issues with manufacturing and the production of samples, only a small sample size was acquired. All the analyses suffered, as a result, making it hard to draw any definite conclusions regarding potential disadvantages with a higher rPET fraction.
GABRIEL, LEANDRO. "Preparação, irradiação e caracterização de blendas PEAD reciclado/EPDM." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26946.
Full textMade available in DSpace on 2016-12-22T16:34:05Z (GMT). No. of bitstreams: 0
A reciclagem de refugos é um processo estratégico que viabiliza a expansão do mercado de plásticos, podendo gerar novos produtos. A obtenção de blendas poliméricas é uma alternativa nesse processo, já que é conhecida a perda de propriedades mecânicas dos termoplásticos nas etapas de reprocessamento. Neste trabalho, o polietileno de alta densidade (PEAD) reciclado teve adições de borracha do monômero etileno-propileno-dieno (EPDM) puro em baixos teores (1 %, 5 % e 10 %), cujo objetivo foi formar blendas miscíveis e um produto final mais resistente ao impacto. O PEAD foi submetido a quatro ciclos de moagem, extrusão e injeção (reprocessamento) e misturado ao EPDM puro por extrusão sem o uso de qualquer aditivo. Os grânulos da blenda formada foram usados para confeccionar os corpos-de-prova por injeção para seu uso nas distintas metodologias analíticas. O processo de irradiação gama foi aplicado nas doses de 50 kGy e 100 kGy e os parâmetros físico-químicos e mecânicos dessas amostras foram comparados aos das não irradiadas. Tanto as blendas irradiadas como as não irradiadas mostraramse visualmente e microscopicamente homogêneas, indicando a compatibilidade da mistura, que também é verificada por seu comportamento térmico. Os parâmetros mecânicos provenientes dos ensaios de tração e flexão, foram semelhantes nas amostras do termoplástico virgem e do reciclado; o processo de irradiação nas blendas gerou sua reticulação, sendo esta verificada não só pelo aumento dos valores desses parâmetros como também pelo aumento da fração gel. A resistência ao impacto aumentou cerca de duas vezes e meia nas amostras com maior teor de EPDM e cerca de 6 a 7 vezes nestas mesmas amostras irradiadas a 50 kGy e 100 kGy respectivamente. O novo material obtido tem fortes indicativos para a sua utilização na pequena e média indústria de plástico, uma vez que já com 1 % de EPDM apresentam melhores características mecânicas em relação ao termoplástico reciclado quatro vezes e essas características foram incrementadas após o processo de irradiação gama.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
Aid, Sara. "Etude de la miscibilité des polymères par la méthode de coalescence des grains en vue du recyclage des DEEE par rotomoulage." Thesis, Paris, ENSAM, 2017. http://www.theses.fr/2017ENAM0059/document.
Full textThe aim of this thesis is to study the miscibility of polymer blends with a view to recycling WEEE polymers by rotomoulding. Indeed, miscibility is a key factor which determines the final properties of polymer blends. The work was divided into two parts. Based on the characterization results of Éco-systèmes WEEE, the choice of materials (PVDF / PMMA) and (ABS / PC) was motivated by the industrial and scientific interest of these two couples. The first part of the work presents an array of experimental methods, ranging from processing to material characterization, with the aim of exploring the miscibility of these mixtures. In particular, the study of the coalescence of the grains made it possible to demonstrate the miscibility of the PVDF / PMMA couple and the partial miscibility of the ABS / PC (coating phenomenon). At the end of this study, the PVDF / PMMA couple was retained as a "model" pair to perform a generalized predictive model of the coalescence between different polymer grains. This model was coupled with a probabilistic parametric analysis to evaluate the effect of the uncertainties of the viscosity, surface tension, relaxation time and grain size measurements on coalescence kinetics. The work ends with a draft of the simulation of the coalescence phenomenon and the coating in the case of miscible and partially miscible polymers respectively
Dořičáková, Michaela. "Studium vlastností polymery modifikovaných malt využívající skelný recyklát." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265690.
Full textSoravia, Valeria. "Towards the circularity of polymer packaging." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Find full textKopf, Sabrina. "Polymer rejuvenation of PET textile waste." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-23819.
Full textFike, Gregory Michael. "Determination of Polymer Film Development through Surface Characterization Studies." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6879.
Full textLi, Ruihua. "Single polymer composites made of slowly crystallizing polymer." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/33925.
Full textSilva, Amanda Helena Marcandali da. "Avaliação do comportamento de pavimentos com camada reciclada de revestimentos asfálticos a frio com emulsão modificada por polímero." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-08072011-160019/.
Full textThis research evaluated in situ cold recycling with emulsion modified by deteriorated asphaltic coating polymer, by analyzing the lab tests results and evaluating Rodovia Régis Bittencourts experimental stretch, currently under Grupo OHL Brasils concession. The lab tests were conducted in order to verify the milled aggregates variety and the effect of the asphaltic emulsions (modified by polymer or conventional) content and type on the cold recycled mixtures dosage, utilizing mechanical behavior results as evaluation parameters. The lab tests show the polymer modified emulsions efficiency over the conventional and the importance of the healing period for the mechanical properties. Lab determined resilience module values were close to the field modules acquired via structural back-analysis, oscillating between 1,000 to 1,500 MPa. The field experiments conception permitted variation of recycled layer thickness (80, 110, and 150 mm) and its type of asphaltic coating (cold asphaltic micro-coating and 40 mm thick asphaltic concrete), resulting in six analyzed segments. The monitoring of the execution contributed to the comprehension of the advantages and limitations of the equipment used for recycling in the field. In monitoring the experimental stretches, there was positive verification that the in situ asphaltic recycling solution brought about better structural and functional condition to the pavements. Deflections were reduced by the cold recycling, and the deflection basins show an increase in curvature radius, thus enhancing structural improvements due to recycling. The field study, that includes monitoring for over 2 years of service life, conclude that the cold asphaltic recycling of deteriorated coatings can be used for heavy traffic, being executable in different thicknesses, varying according to the deteriorated layers state and remnant structure deflections prior to recycling. The cold asphaltic micro-coating can be executed over the asphaltic recycled layer, with limited time efficiency, depending on the acquired deflection after restoration; after a determined period of time, an asphaltic concrete layer must be executed for strengthening. Track observations show that the pavements adequate drainage is a fundamental characteristic for the cold recycling solutions performance.
Gobin, K. "Catalytic degradation of plastic waste to chemicals and fuel as a polymer recycling method." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446571/.
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