Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2017-03-10T14:39:39Z No. of bitstreams: 1 22066.pdf: 9119613 bytes, checksum: 0b28a0c36e553b4d7b70c8a8a0d8d601 (MD5) / Made available in DSpace on 2017-03-10T14:39:39Z (GMT). No. of bitstreams: 1 22066.pdf: 9119613 bytes, checksum: 0b28a0c36e553b4d7b70c8a8a0d8d601 (MD5) / O polímero Acrilonitrila Butadieno Estireno (ABS) é um dos polímeros mais versáteis disponíveis nos dias de hoje. Atualmente o Brasil não produz o ABS, o que limita a indústria brasileira de plásticos a utilizar as variações deste polímero importadas, ofertadas no mercado nacional por distribuidores locais. Este estudo avaliou os efeitos da adição das argilas Cloisite Na® e Branca de Cubati na matriz polimérica ABS e também os efeitos decorrentes do tratamento por radiação ionizante no ABS e nos compósitos ABS/Argila como formas de modificação de um ABS convencional. Visando avaliar a diferença entre uma argila organofílica e uma organofóbica, a argila Branca de Cubati foi organofilizada e a argila Cloisite Na® foi utilizada como recebida. Foram preparados, utilizando uma extrusora dupla rosca, concentrados a 30 % em massa da argila Branca de Cubati, previamente organofilizada e da Cloisite Na® em Estireno Acrilonitrila (SAN). Os concentrados foram adicionados ao ABS a 1, 3 e 5 % em massa das argilas e foram injetados corpos de prova. Parte dos corpos de prova foi submetida à irradiação por feixe de elétrons à uma dose de 600 kGy. Os compósitos irradiados e não irradiados foram caracterizados por meio de ensaios de resistência a tração, resistência a flexão, resistência ao impacto, temperatura de distorção térmica, ponto de amolecimento Vicat, análise de termogravimétrica (TG), difração de raios X e microscopia eletrônica de varredura com emissão de campo (MEVFEG) e a correlação entre os resultados foi discutida. Foram observadas melhorias nas propriedades mecânicas, exceto resistência ao impacto, nos materiais aditivados com as argilas, sendo os melhores resultados obtidos com a argila Branca de Cubati. O tratamento por radiação ionizante favoreceu o processo de reticulação do ABS. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

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.

No description available.

Polyethylene (PE) resins being non-polar in nature and having a high degree of crystallinity have limited miscibility and compatibility when blended with polar polymers. The miscibility and compatibility of these blends are generally worsened when they are prepared by direct injection moulding without a precompounding process. Such situations are commonly encountered in particular by polymer converters when blending colour and/or additive concentrates, commonly known as masterbatches. Typically, masterbatches are mixtures containing high loading of pigments and/or additives predispersed in a suitable solid vehicle (commonly known as carrier) such as a polyethylene resin. These masterbatches are usually used for the colouration of a wide range of polymers and the carrier used must therefore be compatible with these matrix (host) polymers. The preliminary stage of this study involved the investigation of the properties of blends based on high density polyethylene (HDPE) and a range of engineering thermoplastics (ABS, PC, PBT, PA6), prepared by injection moulding. Five different types of compatibilisers namely, ethylene-vinyl acetate (EVA) copolymer, ethylene-methyl acrylate (EMA) copolymer, ethylene-glycidyl methacrylate (E-GMA) copolymer, ethylene-methyl acrylateglycidyl methacrylate (E-MA-GMA) terpolymer and maleic anhydride grafted HDPE (HDPE-g-MAH) copolymer were evaluated with respect to their efficiencies in compatibilising HDPE with the four engineering polymers. The pre-compounded HDPE/compatibiliser binary blends at 2 different blend ratios (1:1 and 3:1) were added at 15 wt% concentration to each engineering thermoplastics and test samples were produced directly by injection moulding. Results of mechanical testing and characterisation of the blends showed that glycidyl methacrylate compatibilisers, E-MA-GMA, in particular have the most universal compatibilising effectiveness for a range of engineering thermoplastics including ABS, PC, PBT, and PA6. Blends compatibilised with E-MA-GMA compatibiliser had the best notched impact performance irrespective of matrix polymer type. The presence of an acrylic ester (methyl acrylate) comonomer in E-MA-GMA resulted in increased polarity of the ii compatibiliser leading to improved miscibility with the polar matrix polymers demonstrated by fine blend morphologies, melting point depression and reduction in crystallinity of the HDPE dispersed phase. The second stage of this study involved the reactive modification of HDPE using a low molecular weight di-functional solid diglycidyl ether of bisphenol A (DGEBA) type epoxy resin compatibilised with HDPE-g-MAH in an attempt to improve its compatibility with ABS, PBT and PA6. The maleic anhydride moieties in HDPE-g-MAH served as reactive sites for anchoring the epoxy moieties while the HDPE backbone was miscible with the HDPE resin. An excessive amount of reactive groups resulted in the formation of crosslinked gels while the addition of EVA co-compatibiliser helped in the reduction of gel content and further improved the dispersion of the epoxy. The effectiveness of epoxy grafted HDPE (with and without EVA co-compatibiliser) in compatibilising ABS/HDPE, PBT/HDPE, and PA6/HDPE was investigated by injection moulding of 5 wt% functionalised HDPE with these matrix polymers into test bars for mechanical testing, and characterisation by differential scanning calorimtery (DSC) and optical microscopy. The reactively functionalised HDPE blends, improved the mechanical properties of ABS and PA6 blends especially with EVA as co-compatibiliser. However, the mechanical properties of PBT blends were unmodified by the functionalised HDPE which was believed to be due to end-capping of the PBT chain-ends by ungrafted epoxy resins.

The theoretical part of this thesis is focused on bulk radical polymerization of styrene, methylmethacrylate, vinyltoluene and paramethylstyrene. It summarizes actual informations about kinetics and performance possibilities of bulk polymerization. Experimental part deals with polystyrene prepolymers preparation by bulk polymerization. The aim is to find optimal conditions for prepolymers preparation. Prepolymers should be usable for subsequent polymerization nearly up to 100% conversion. Conversion values were gravimetrically determined and molecular weights were obtained by viskosity measurements, which were realized by Ubbelohde viscometer. In the experimental part, there were performed simulations targeted on conversion dependence on time. The purpose was a prediction of monomer conversion at a given time during polymerization. Differences between reality and simulation were low in most of cases and the found form of kinetic behavior calculations provides satisfying results. In the conclusion of this thesis was suggested a new procedure for polystyrene prepolymers preparation.

Dan Beaty (1937-2002) was a prolific composer, pianist, researcher, educator, and writer. His large compositional output included chamber works, choral works, songs, orchestral pieces, electronic music, and keyboard works. Beaty was well versed in traditional Western music as well as the more avant-garde and perplexing idioms of the twentieth century. Beaty's compositions reflect the many fascinating, if not always popular, musical trends of his time. His music encompasses styles from serial to jazz, shows compositional influences from Arnold Schoenberg to Indonesian music, and demonstrates thought-provoking and highly intellectual craftsmanship. This document explores several of Beaty's songs through a discussion of the composer's life and compositional process. Songs included in this document are Three Weeks Songs, October, November, A Sappho Lyric, Love Song, That Night When Joy Began, and War Lyrics. This document was written to accompany the author's DMA Lecture-Recital at the University of North Texas. Unfortunately, Beaty's vocal music was never published and is mostly unknown. One goal of the project was to initiate interest in Beaty's songs. Through this document, Lecture-Recital, and additional performances, considerable strides have been made to bring Beaty's songs to new audiences throughout the United States. In addition, the author has received permission from the Beaty family to publish Dan Beaty's songs.

Ce travail concerne l'étude des modifications de nanocharges lamellaires synthétiques (α-ZrP) et de leur influence sur les propriétés mécaniques et barrière aux gaz de nanocomposites à matrice élastomère (SBR). Cette étude s'inscrit dans le cadre de l'amélioration de l'étanchéité des pneumatiques. L'une des originalités de ce travail a résidé dans l'introduction des nanocharges hydrophiles par le biais d'une dispersion aqueuse (slurry), dans la matrice SBR hydrophobe. La première phase de ce travail a consisté à entreprendre plusieurs types de modification des nanocharges afin d'étudier les mécanismes d'intercalation et/ou d'exfoliation des ces dernières dans le slurry. Ces différentes familles de charges modifiées ont été utilisées pour réaliser des nanocomposites selon différentes voies de mise en oeuvre : principalement solvant et latex. Nous avons ensuite étudié l'influence, (i) de la nature des intercalants, (ii) des distances interfoliaires initiales des nanocharges et (iii) des procédés de mise en oeuvre des nanocomposites, sur la morphologie et les propriétés finales des matériaux. Cette étude a montré la synergie de ces trois paramètres et mis en évidence l'importance du contrôle des interactions charges modifiées/matrice sur les propriétés de transport de gaz. Parmi l'ensemble des matériaux synthétisés, nous avons pu mettre en avant une formulation, permettant d'atteindre des propriétés mécaniques et barrière intéressantes. Cette formulation, en voie latex, est basée sur l'utilisation de la charge modifiée aminosilane et de l'agent de couplage Si69 / This work concerns the study of the modification of synthetic lamellar nanofillers (α-ZrP) and their influence on mechanical and gas barrier properties of elastomeric nanocomposites (SBR). This study is part of improving the tire tightness. One of the originalities of this work is the introduction of hydrophilic nanofillers through an aqueous dispersion (slurry) in the hydrophobic SBR matrix. The first step of this work was to undertake several types of nanofiller modifications state in order to study their intercalation/exfoliation mechanisms in a slurry. These different families of modified fillers were then used to make nanocomposites with different ways of implementations: mainly solvent and latex ones. The influence of, (i) the nature of the intercalating agent, (ii) the initial nanofiller interlayer distance and (iii) the nanocomposite implementation processes, on the morphology and final properties of materials were studied. The synergy of these three parameters was demonstrated and the importance of controlling the modified filler/matrix interactions on the gas transport and mechanical properties was also proved. Among all the synthesized materials, a formulation was put forward which allowed to achieve interesting mechanical and barrier properties. This formulation, processed by the latex route, is based on the use of aminosilane modified nanofillers and the Si69 coupling agent

Les objectifs de cette thèse consistent à identifier les morphologies adoptées par des mélanges d’élastomères chargés en noir de carbone, à étudier l’influence de l’introduction de charges sur ces morphologies mais aussi de détecter la localisation de la charge dans ces mélanges. Dans une dernière partie, l’impact de ces différentes structures sur les défauts d’extrusion est abordé. Ces travaux concernent l’étude des coupages caoutchouc naturel / styrene-butadiene rubber (NR / SBR) et polybutadiène / styrene-butadiene rubber (BR / SBR) non vulcanisés. Dans un premier temps, les morphologies adoptées par ces mélanges non chargés ont été identifiées grâce à plusieurs protocoles expérimentaux. L’influence de l’introduction de noir de carbone ainsi que l’étude de la localisation de la charge dans ces mélanges ont constitué une seconde étape dans ces travaux. Aucune localisation préférentielle de la charge n’a été détectée pour ces mélanges. Un système ségrégé a donc été réalisé par la suite. Enfin, le comportement en extrusion de ces mélanges a été simulé par rhéométrie capillaire et des observations de défauts d’aspect ont été faites. La ségrégation du noir de carbone ne semble pas entraîner la création de défauts d’aspect, sauf dans le cas d’une localisation dans la matrice / The purpose of this project is to investigate the morphology of elastomeric blends filled with carbon black, the localization of the filler in these blends and the structure impact on their processing. This work concerns uncured natural rubber / styrene-butadiene rubber (NR / SBR) blends and butadiene rubber / styrene-butadiene rubber (BR / SBR) blends. Firstly, the morphology of these blends unfilled was described by different experimental procedures over the entire composition range. Secondly, the impact of the filler on the morphology and the localization of it on the blends were studied. No preferential localization was observed in our case. Another blend with a segregation was realized. And finally, the processing of these elastomeric blends was simulated by capillary rheology to detect the formation of flow instabilities. Few melt fractures were observed, except when the filler is localized in the matrix

Purpose: This paper will present insight to the methodology and results of the experimental characterization of Acrylonitrile Butadiene Styrene (ABS) using Fused Deposition Modeling (FDM). The work in this research explored the effects of print orientation, surface treatment, and ultraviolet (UV) light degradation with the utilization of Digital Image Correlation (DIC) on ABS tensile specimens. Design/methodology: ABS specimens were printed at three build orientations (flat (0 degrees), 45 degrees, and up-right (90 degrees)). Each of these specimens were treated with three different surface treatments including a control (acrylic paint, Cyanoacrylate, and Diglycidyl Bisphenol A) followed by exposure to UV light to the respective batches. This experiment design will provide tensile direction properties with the effect of thermoset coatings and UV degradation. Dogbone FDM specimens based on ASTM standard D638 type IV were printed on a Stratasys Dimension SST (Soluble Support Technology) 1200es 3D Printer and loaded into a MTS Landmark Servohydraulic Test Systems. Analysis was preformed on the fracture section of the tensile specimens utilized DIC and comparing Ultimate Tensile Strength (UTS) and Ultimate Fracture Strength (UFS). Findings: From the results UV light did not play a large factor in the strength of the specimens. The print orientation showed the largest anisotropic behavior where some specimens experienced as much as a 54% difference in ultimate tensile strength. Thermoset coated specimens experienced a maximum of 2% increase in strength for the Cyanoacrylate and Diglycidyl Bisphenol A specimens where the acrylic paint and natural did not. Several findings were of value when looking at the stress strain plots. Originality/value: This paper provides knowledge to the limited work on print build orientation, thermoset coatings and, UV light on ABS specimens. Very little to no work has been done on these three properties. This paper can serve as the foundation of future work on external applications on ABS plastics.

No description available.