• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 61
  • 47
  • 7
  • 6
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 165
  • 165
  • 62
  • 54
  • 43
  • 30
  • 25
  • 24
  • 24
  • 24
  • 18
  • 17
  • 17
  • 17
  • 16
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Diagnóstico da gestão de resíduos de equipamentos eletroeletrônicos e proposta de modelo em um contexto de green supply chain management / Diagnosis of WEEE management and proposal of a model in a Green Supply Chain Management context

Castro, Marco Aurélio Soares de 17 October 2014 (has links)
Ao longo do ciclo de vida de um produto, a empresa que o disponibiliza interage com diversas outras organizações, tanto no fluxo direto como no fluxo reverso da cadeia estabelecida, além do consumidor. Assim, para a gestão dos aspectos e impactos ambientais desse produto, é necessário considerar as contribuições de atores como fornecedores, produtores, consumidores e organizações da cadeia reversa que coletam e processam os resíduos gerados. Isso implica adotar o conceito de Green Supply Chain Management (Gestão Ambiental da Cadeia de Suprimentos), o que, entre outros benefícios, permite maior eficiência na gestão de resíduos sólidos gerados ao longo da cadeia, especialmente após o fim da vida útil do produto. Ainda na área de resíduos sólidos, os resíduos de equipamentos eletroeletrônicos se caracterizam por conterem diversas substâncias que os tornam potencial fonte de matérias-primas e de riscos à saúde e ao meio ambiente. Sua geração extremamente difusa dificulta a caracterização quali-quantitativa e portanto sua gestão e gerenciamento adequados. Neste contexto, a presente pesquisa, suportada por revisões bibliográfica e sistemática e por estudos de caso em organizações do município de São Carlos (SP) e de outros municípios que integravam uma mesma cadeia, apresenta um diagnóstico quali-quantitativo da gestão de REE gerados a partir de computadores pessoais descartados na área urbana do município e propõe diretrizes de um modelo de gestão destes resíduos que adota princípios de Green Supply Chain Management. Foi observado que já há disponibilidade técnica para a reutilização, via remanufatura, e a reciclagem de computadores pessoais, porém a deficitária infraestrutura para coleta e armazenamento é um fator limitante para a gestão e gerenciamento adequados. Constatou-se também que a interação e colaboração entre diferentes atores da cadeia identificada pode contribuir para aperfeiçoar a gestão deste tipo de REE. / Throughout the life cycle of a product, its manufacturer interacts with various other organizations, on both the direct and reverse flows of the established chain, as well as the customer. Therefore, in order to manage the environmental aspects and impacts of that product, it is necessary to consider the contributions of participants such as suppliers, producers, consumers and reverse chain organizations that collect and process the waste generated. This implies adopting the concept of Green Supply Chain Management, which, among other benefits, allows greater efficiency in the management of solid waste generated along the chain, especially when the product reaches its end of life. Still in the field of solid waste, waste electrical and electronic equipment (WEEE) are characterized by containing various substances that make them potential sources of precious raw materials and, simultaneously, risks to health and the environment. Its extremely diffuse generation makes quali-quantitative characterizations and therefore its proper management more difficult. In this context, the research reported here, comprised of bibliographic and systematic reviews and case studies in organizations in São Carlos (SP) and other cities that are part of the same chain, presents a quali-quantitative diagnosis of REE management generated from personal computers discarded in the urban area of that city and proposes guidelines of a management model that adopts Green Supply Chain Management principles. It was observed that there is already technical availability for reuse (after remanufacturing) and recycling of personal computers, but poor infrastructure for collection and storage is a limiting factor. It was also noted that the interaction and cooperation between different actors in the identified chain may contribute to improve the management of this type of WEEE.
132

Analytical strategies for the quality assessment of recycled high-impact polystyrene (HIPS)

Vilaplana Domingo, Francisco Javier 30 May 2008 (has links)
Polymers are subjected to physical and chemical changes during their processing, service life, and further recovery, and they may also interact with impurities that can alter their composition. These changes substantially modify the stabilisation mechanisms and mechanical properties of recycled polymers. The assessment of the quality properties of recycled polymers is therefore crucial to guarantee the performance of recyclates in further applications. Three key quality properties have been defined for this quality analysis: degree of mixing (composition), degree of degradation, and presence of low molecular weight compounds (degradation products, contaminants, additives). Furthermore, detailed knowledge about how the different stages of their life cycle affect the degree of degradation of polymeric materials is important when discussing their further waste recovery possibilities and the performance of recycled plastics. A dual-pronged experimental approach employing multiple processing and thermo-oxidation has been proposed to model the life cycle of recycled high-impact polystyrene (HIPS used in packaging applications, and electrical and electronic equipment (E&E). Both reprocessing and thermo-oxidative degradation are responsible for coexistent physical and chemical effects (chain scission, crosslinking, apparition of oxidative moieties, polymeric chain rearrangements, and physical ageing) on the microstructure and morphology of polybutadiene (PB) and polystyrene (PS) phases; these effects ultimately influence the long-term stability, and the rheological and mechanical behaviour of HIPS. The PB phase has proved to be the initiation point of HIPS degradation throughout the life cycle. Thermo-oxidation seems to have more severe effects on HIPS properties; therefore, it can be concluded that previous service life may be the part of the life cycle with the greatest influence on the recycling possibilities and performance of HIPS recyclates in second-market applicat / Vilaplana Domingo, FJ. (2008). Analytical strategies for the quality assessment of recycled high-impact polystyrene (HIPS) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/2186 / Palancia
133

Two-Phase Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics using Practical Enhanced Surfaces

Altalidi, Sulaiman Saleh 08 1900 (has links)
The objective of this research was to investigate the performance of two-phase spray cooling with HFC-134a and HFO-1234yf refrigerants using practical enhanced heat transfer surfaces. Results of the study were expected to provide a quantitative spray cooling performance comparison with working fluids representing the current and next-generation mobile air conditioning refrigerants, and demonstrate the feasibility of this approach as an alternative active cooling technology for the thermal management of high heat flux power electronics (i.e., IGBTs) in electric-drive vehicles. Potential benefits of two-phase spray cooling include achieving more efficient and reliable operation, as well as compact and lightweight system design that would lead to cost reduction. The experimental work involved testing of four different enhanced boiling surfaces in comparison to a plain reference surface, using a commercial pressure-atomizing spray nozzle at a range of liquid flow rates for each refrigerant to determine the spray cooling performance with respect to heat transfer coefficient (HTC) and critical heat flux (CHF). The heater surfaces were prepared using dual-stage electroplating, brush coating, sanding, and particle blasting, all featuring "practical" room temperature processes that do not require specialized equipment. Based on the obtained results, HFC-134a provided a better heat transfer performance through higher HTC and CHF values compared to HFO-1234yf at all tested surfaces and flow rates. While majority of the tested surfaces provided comparable HTC and modestly higher CHF values compared to the reference surface, one of the enhanced surfaces offered significant heat transfer enhancement.
134

Ökonomische Analyse der Rückgewinnung von hochwertigen Metallen aus elektrischen und elektronischen Altgeräten in Deutschland

Greif, Steffi 03 December 2009 (has links)
Die vorliegende Ausgabe beschäftigt sich mit dem Thema „Ökonomische Analyse der Rückgewinnung von hochwertigen Metallen aus elektrischen und elektronischen Altgeräten in Deutschland“. Elektro- und Elektronikgeräte sind aus dem täglichen Leben nicht mehr wegzudenken; die Unternehmen entwickeln und produzieren immer leistungsfähigere Produkte, wobei durch die immer schnelleren und kurzlebigeren Innovationszyklen die Abfallberge ausgedienter Elektro(nik)geräte beständig wachsen. Mit Inkrafttreten des Elektro- und Elektronikgerätegesetz am 24. März 2005 werden alte Elektro(nik)geräte zukünftig getrennt gesammelt und weitgehend verwertet. Neu ist, dass die Hersteller mehr Verantwortung für ihre Produkte übernehmen und zur Verwertung der getrennt gesammelten Elektro- und Elektronik-Altgeräten verpflichtet sind. Das Elektro- und Elektronikgerätegesetz geht zum einen aus der europäischen Richtlinie über die Entsorgung von Elektro- und Elektronik-Altgeräten (WEEE) und zum anderen aus der europäischen Richtlinie über die Verwendung bestimmter gefährlicher Stoffe in Elektro- und Elektronikgeräten (RoHS) hervor und gilt als Reaktion auf die wachsenden Elektro(nik)schrott-Berge. Für die Unternehmen der Entsorgungs- und Recyclingbranche ergeben sich mit diesen gesetzlichen Neuerungen neue Chancen auf Weiterentwicklung ihres Geschäftsfeldes. Besonderes Augenmerk gilt den Demontageunternehmen, mit deren Hilfe erst die gesetzlichen Forderungen, hinsichtlich der zu erzielenden Rückgewinnungsquoten und der notwendigen selektiven Behandlung einiger Baugruppen, erfüllt werden können. Die Rückgewinnung hochwertiger Metalle aus Elektro(nik)schrott bedarf im Hinblick der Preissteigerungen auf den Rohstoffmärkten höchster Priorität. Mit Etablierung eines Sekundärrohstoffmarktes kann ein rohstoffarmes Land wie Deutschland der Abhängigkeit des Importes von Primärrohstoffen signifikant entgegenwirken.
135

An evaluation of electronic waste management in Ba-Phalaborwa local municipality, Limpopo Province, South Africa

Tshimbana, Tsakani Permlar 30 May 2014 (has links)
An evaluation of electronic waste (e-waste) management in Ba-Phalaborwa Local Municipality was undertaken in this study. The aim of the study was to evaluate the electronic waste management practices such as generation, storage, collection, transportation and disposal in Ba-Phalaborwa Local Municipality. This was achieved through questionnaires distributed to residents in Namakgale and Phalaborwa residential areas, structured interviews with municipal workers under the Environmental Health Division and observation in the landfill site and collection points were also used in gathering information on the electronic waste management. In the study it was found that a wide range of electronic waste is generated and lighting equipment, small household equipment and ICT equipment are disposed of in large numbers in the study area. The municipality is responsible for waste management in the study area. Electronic waste generated is stored, collected and disposed together with all other domestic waste in the area. No segregation or recycling at household level was evident. It was also found that the municipality does not have a formal relationship with electronic waste recycling companies to eliminate the flow of electronic waste from households to the landfill site. A lack of own regulatory and by-laws on electronic waste was noted and seemed to be one of the challenges the municipality is facing. The findings highlighted the low level of community awareness regarding electronic waste. The study concluded that there is a lack or absence of good management of electronic waste storage, collection, transportation in the Ba-Phalaborwa Local Municipality. From the study, it is recommended that there is a need for meaningful community awareness, environmental education, formulation of by-laws and formal recycling projects for effective electronic waste in Ba-Phalaborwa Local Municipality. / Environmental Sciences / M. Sc. (Environmental Management)
136

An evaluation of electronic waste management in Ba-Phalaborwa local municipality, Limpopo Province, South Africa

Tshimbana, Tsakani Permlar 30 May 2014 (has links)
An evaluation of electronic waste (e-waste) management in Ba-Phalaborwa Local Municipality was undertaken in this study. The aim of the study was to evaluate the electronic waste management practices such as generation, storage, collection, transportation and disposal in Ba-Phalaborwa Local Municipality. This was achieved through questionnaires distributed to residents in Namakgale and Phalaborwa residential areas, structured interviews with municipal workers under the Environmental Health Division and observation in the landfill site and collection points were also used in gathering information on the electronic waste management. In the study it was found that a wide range of electronic waste is generated and lighting equipment, small household equipment and ICT equipment are disposed of in large numbers in the study area. The municipality is responsible for waste management in the study area. Electronic waste generated is stored, collected and disposed together with all other domestic waste in the area. No segregation or recycling at household level was evident. It was also found that the municipality does not have a formal relationship with electronic waste recycling companies to eliminate the flow of electronic waste from households to the landfill site. A lack of own regulatory and by-laws on electronic waste was noted and seemed to be one of the challenges the municipality is facing. The findings highlighted the low level of community awareness regarding electronic waste. The study concluded that there is a lack or absence of good management of electronic waste storage, collection, transportation in the Ba-Phalaborwa Local Municipality. From the study, it is recommended that there is a need for meaningful community awareness, environmental education, formulation of by-laws and formal recycling projects for effective electronic waste in Ba-Phalaborwa Local Municipality. / Environmental Sciences / M. Sc. (Environmental Management)
137

Le retour du commun au cœur de l’action collective : le cas de la Responsabilité Élargie du Producteur comme processus de responsabilisation et de co-régulation / The return of the Commons at the heart of collective action : the case of Extended Producer Responsibility as a process of responsibilization and co-regulation

Micheaux, Helen 24 November 2017 (has links)
Le modèle de production et de consommation linéaire, qui se résume à: extraire, produire, utiliser puis jeter, menace la préservation de nos ressources naturelles, alors même que les Déchets d’Équipements Électriques et Électroniques (DEEE) constituent des « mines urbaines » riches en métaux de valeur. Les politiques publiques classiques des années 70, fondées sur une approche régalienne, se sont révélées inefficaces pour stimuler des démarches innovantes et collectives.Dans cette thèse, nous étudions une approche alternative fondée sur un principe de responsabilisation des producteurs, encadrés par une forme de co-régulation entre acteurs publics et privés. Alors que la responsabilité est souvent associée à une logique individuelle, qu’est-ce qu’une responsabilité collective? Plus encore, pour faire de la responsabilisation une technique politique de gouvernement, quels processus et instruments s’agit-il de mobiliser pour rendre des acteurs collectivement responsables?À travers le cas de la filière des DEEE, cette thèse propose des principes de la co-régulation. Nous nous appuyons sur la littérature sur les communs, où ont été discutées les conditions d’une gestion et d’une gouvernance collectives. La thèse repose sur une approche exploratoire, qualitative et longitudinale. Une analyse comparative au niveau européen permet une mise en perspective des propositions théoriques. / The Linear Economy is structured on: extraction, production, product use and landfill. This model prevails although it is a threat to the preservation of natural resources. Whereas, Waste Electrical and Electronic Equipment (WEEE) constitute “Urban Mines” that are rich in valuable metals. Public policies from the 70s, based on regulatory constraints, have proved to be inefficient in instigating innovative and collective processes.In this thesis, we study an alternative approach based on the responsabilization of producers through co-regulated action between public and private actors. While responsibility is often linked to individualism, this work scrutinizes the substance of collective responsibility. Furthermore, in consideration of responsabilization as a mode of political governance, we examine the processes and the instruments which could be engaged to bestow collective responsibility on private actors.Through an exploratory, qualitative and longitudinal approach in the context of the WEEE sector, we propose new co-regulation principles. The research is based on the literature of the commons in which the conditions of a collective governance are discussed. The theoretical propositions are considered in the perspective of a comparative analysis at the European level.
138

Ciclos de atividade/repouso e alimentação/jejum associados ao uso de equipamentos eletrônicos: aspectos comportamentais e padrões temporais / Not informed by the author

Seito, Tatiana Harumi 27 January 2017 (has links)
A energia elétrica de uso doméstico no cenário mundial é um fenômeno recente que incorporou modulações temporais na expressão dos ritmos biológicos, como os hábitos alimentares e de sono. Após sua popularização, tecnologias eletrônicas foram criadas e incorporadas às nossas rotinas diárias. O acesso à iluminação elétrica promove uma maior flexibilidade na organização temporal das nossas atividades por facilitar o controle de extensão da fase de atividade para horas mais tardias da noite. Assim, essa situação pode constituir um desafio temporal ao organismo, gerado pelas oscilações das pistas temporais, adiantando ou atrasando a ocorrência de eventos rítmicos como a alimentação/jejum, atividade/repouso e metabolismo. O estudo foi realizado com 27 universitários entre 18 a 30 anos (17 mulheres; 10 homens) nos quais o comportamento alimentar e de sono foi registrado por meio do uso de diários e os ciclos de atividade/repouso e claro/escuro por meio de actímetros. Observada uma associação indireta entre o uso de equipamentos eletrônicos e o aumento no consumo alimentar. A associação observada em relação ao uso dos equipamentos com a ingesta está mais amparada no atraso do início do sono que propicia o aumento observado da ingesta média na fase noturna. No longo prazo o atraso da fase do sono e a diminuição da sua duração pode gerar um desalinhamento na regulação da expressão dos padrões temporais de atividade/repouso e alimentação/jejum que pode alterar o padrão do comportamento alimentar / Electric energy used widely in domestic context is a recent phenomenon that incorporates temporal modulations on the expression of biological rhythms and behaviour, like food ingestion and sleep patterns. After popularization of electric energy, electronic technologies have been created and incorporated to our routines. Access to electric light can promote more flexibility on temporal organization of our activities which allow for an extension of the wake phase to later portions of the night. Thus, that situation could promote temporal challenges to the organisms, generated by oscillations of temporal signals, which may cause phase advances or delays in rhythmic events like feeding/fasting, rest/activity and metabolic functions. This study involved 27 university students between 18 to 30 years old (17 women; 10 men) where feeding and sleep behavior data were collected with feeding and sleep diaries; the rest/activity rhythm and the light/dark cycle data were collected with actimeters. The association observed in relation to the use of the electronic equipments with the food intake is supported by the delay of the beginning of rest that propitiates the increase of the average intake in the nocturnal phase. In the long term, the delay of the rest phase and the decrease of its duration can generate a misalignment in the regulation of the expression of the temporal patterns of rest/activity and feeding/fasting and thus change the temporal pattern of the feeding behavior
139

Resíduos de equipamentos elétricos e eletrônicos em instituições de ensino superior: estudo de caso e diretrizes para elaboração de plano de gestão integrada / Electrical and electronic equipment waste in Higher Education Institutions: a case study and guidelines for the development of an integrated management plan

Reidler, Nivea Maria Vega Longo 27 March 2012 (has links)
Introdução: no Brasil, ainda não há legislação específica, em nível nacional, sobre resíduos de equipamentos elétricos e eletrônicos (REEE). Com a regulamentação da Política Nacional de Resíduos Sólidos, as instituições de ensino superior (IES) no país se deparam com a necessidade de criar sistemas de gestão integrada que incluam logística reversa e disposição desses equipamentos ao final de sua vida útil. Objetivo: estudar a geração, fluxo e destino dos REEE de IES e propor diretrizes para a gestão institucional desses resíduos. Estudou-se o caso de duas IES, em dois cenários distintos: A) a Universidade de São Paulo (Brasil), sem influência de legislação específica sobre o tema e que não possui política de resíduos consolidada; B) A Universidade de Cádiz (Espanha), sob influência das Diretivas da União Europeia e de legislação nacional e que conta com política de resíduos e sistemas integrados de gestão de REEE. Método: análise quali/quantitativa em ambas as IES que constou de: I) Diagnóstico da geração, fluxo e destino dos REEE. Técnica utilizada: levantamento dos dados censitários dos bens que sofreram processo de baixa em um período de dez anos, no sistema de informação da Administração Patrimonial; II) Criação de nova base de dados, com inclusão de classificação dos REEE por tipo, peso médio e periculosidade; III) Pesquisa participativa com os responsáveis por setores envolvidos com a gestão interna de REEE; e IV) Observação sistemática, com registros fotográficos e de dados obtidos, em locais de destino de REEE e em nove Sistemas de Gestão Integrada de REEE (SIG-REEE) da Espanha. Resultados: o diagnóstico foi apresentado aos responsáveis por setores envolvidos com a gestão interna desses resíduos nas instituições, com objetivo de coletar sugestões para um plano de gestão de REEE que atendesse às suas necessidades e expectativas. Os resultados desta pesquisa levaram à proposta de diretrizes para a gestão institucional de REEE, orientando a execução das ações de controle de seus impactos econômicos, sociais, ambientais e de saúde de forma integrada e que seja sustentável e possa ser adaptado a quaisquer tipos de instituição, com flexibilidade para atender a diferentes necessidades e realidades. Conclusão: I) Os procedimentos adotados atualmente nas IES estudadas não atendem aos requisitos fundamentais de sustentabilidade. II) Constatou-se que fatores internos determinam os caminhos da gestão externa do REEE. III) As diretrizes propostas para gestão integrada de REEE baseiam-se em três etapas principais: a) planejamento para aquisição do EEE; b) vida útil; c) gestão de REEE. O estudo conclui que para se conseguir um sistema de gestão sustentável e efetivo, é necessário considerar todas as etapas do ciclo de vida do produto, a partir do planejamento para sua aquisição, até seu destino final. Para que o sistema de gestão de REEE em IES seja efetivo, propõe-se a integração da gestão de EEE/REEE / Introduction: in Brazil, there is no specific law at the national level for the disposal of electrical and electronic equipment waste (WEEE). With the National Solid Waste Policy regulations, Higher Education Institutions (HEI) in the country are faced with the need to create integrated management systems that include reverse logistics and disposal of such equipment at the end of its life time. Objective: to study the generation, flow, and destination of WEEE from HEI and propose guidelines for developing an institutional management system for such waste. Two HEIs in two distinct scenarios were analyzed: A) the University of São Paulo (Brazil), which operates without the influence of legislation on the subject and does not have a consolidated waste policy; and B) The University of Cádiz (Spain), which operates under European Union Directives and national legislation, featuring an integrated waste management policy on WEEE. Methods: qualitative/quantitative analyses in both institutions consisted of: i) Diagnosis of the generation, flow, and destination of WEEE based on census data on goods that have undergone a process of decline over a period of ten years in the Administração Patrimonial (Asset Management) information systems; ii) Creation of a new database, which includes the classification of WEEE by type, average weight, and hazard risk; iii) Research with the participation of the responsible parties of the sectors involved with the internal management of WEEE, and iv) Systematic observation, with photographic records and retrieved data from WEEE destinations and from nine Integrated Management Systems of WEEE (SIG-REEE) in Spain. Results: the diagnoses were presented to the responsible parties of the sectors involved with the internal management of such waste in institutions, with the objective of gathering suggestions for a WEEE management system that meets needs and expectations. The results led to the proposal of guidelines for the preparation of an institutional WEEE management plan, to orient the implementation of sustainable practices in order to better control economic, social, environmental, and health impact in an integrated manner that is sustainable and can be adapted to any type of institution, with enough flexibility to meet different needs and realities. Conclusion: I) the procedures currently in effect in HEI do not meet the core requirements of sustainability II) It was noted that internal factors determine the paths of external WEEE management. III) The guidelines proposed in this study for integrated management of WEEE were based on three main stages: a) acquisition of the EEE, b) useful life period; c) WEEE management. The study concludes that to achieve a sustainable and effective management system, it is necessary to consider all stages of the life cycle of a product, from planning to acquisition, to its final destination. The integration of EEE/WEEE management is recommended
140

Reciclagem do copolímero acrilonitrila-butadieno-estireno e do poliestireno de alto impacto oriundos de rejeitos de equipamentos elétricos e eletrônicos na forma de blendas poliméricas / Recycling of copolymer acrylonitrile-butadiene-styrene and high impact polystyrene from waste electrical and electronic equipment in the form of polymer blends

Hirayama, Denise 14 August 2015 (has links)
O crescimento na geração de rejeitos de equipamentos elétricos e eletrônicos (REEE), legislações mais rigorosas e o valor agregado destes materiais incentivam o desenvolvimento de tecnologias de reciclagem. Contudo, a reciclagem dos componentes poliméricos dos REEE (CP-REEE) precisa superar desafios como a degradação durante o uso e reprocessamento, a presença de diferentes aditivos nos rejeitos e a depreciação de propriedades causada pela mistura não controlada de polímeros. Assim, o objetivo deste trabalho foi desenvolver um estudo sobre a reciclagem mecânica na forma de blendas poliméricas de rejeitos do copolímero acrilonitrila-butadieno-estireno (ABS) e do poliestireno de alto impacto (HIPS), empregando agentes compatibilizantes. No desenvolvimento do trabalho foram realizadas a caracterização dos CP-REEE, análise das propriedades mecânicas, químicas, térmicas e morfológicas dos polímeros e das blendas de ABS/HIPS nas proporções de 1:3, 1:1 e 3:1 com variações na composição dos polímeros reciclados e virgens e por fim, realizado um estudo do envelhecimento foto-oxidativo acelerado de uma blenda ABS/HIPS. Os resultados mostraram que os polímeros ABS e HIPS reciclados ainda apresentam boas propriedades mecânicas e que a presença de agentes compatibilizantes provoca o aumento da tenacidade nas blendas ABS/HIPS. A incorporação de polímeros virgens nos materiais reciclados não promove ganho significativo nas propriedades mecânicas das blendas. Blendas com até 50% de ABS demonstraram ter propriedades próximas às do HIPS, enquanto as blendas com altos teores de ABS não alcançaram valores de propriedades mecânicas similares aos do ABS virgem. O comportamento das propriedades das blendas virgens e recicladas frente ao envelhecimento fotoquímico foi similar, indicando que o material reciclado apresenta grande potencial para aplicações. O estudo de blendas ABS/HIPS de CP-REEE demonstra que o controle da composição das blendas definem a sua aplicação. / The growth in waste electrical and electronic equipment (WEEE) generation, directives more stringent and the aggregate value presents in these waste are encouraging the development of recycling technologies. However, recycling of polymeric components from WEEE (PC-WEEE) must overcome challenges such as degradation during use and reprocessing, the presence of various additives in the waste and the depreciation of properties caused by uncontrolled polymers mixture. The aim of this work was to develop a study of the mechanical recycling in the form blends with of polymeric waste of acrylonitrile-butadiene-styrene copolymer blends (ABS) and high impact polystyrene (HIPS) using compatibilizers. During the study was carried out the characterization of the PCWEEE and mechanical, chemical, thermal and morphological analysis of the polymers and the ABS / HIPS blends in proportions of 1:3, 1:1 and 3:1 with recycled and virgin polymers, as well as a study of the accelerated photo-oxidative aging of the ABS/HIPS blends. The results showed that ABS and HIPS recycled polymers still have good mechanical properties and the presence of compatibilization agents leads to increased toughness in ABS/HIPS blends. The incorporation of virgin polymers in recycled materials does not promote significant gain in the mechanical properties of the blends. Blends with up to 50% ABS have demonstrated to be closer to the HIPS, while blends with high content of ABS did not reach values of mechanical properties similar to the virgin ABS. The mechanical properties of virgin and recycled blends during the photochemical aging were similar, indicating that the recycled material has great potential for applications. The study of ABS/HIPS blends from PC-WEEE demonstrated that control of the blend composition establish their applications.

Page generated in 0.1059 seconds