Com o advento de plataformas flutuantes dispostas em laminas d’água, cada vez mais profundas, o desenvolvimento de linhas de ancoragem mais leves, resistentes e economicamente viáveis, foram e estão sendo desenvolvidas, sendo os materiais poliméricos os mais promissores. O poliéster, pela excelente combinação de propriedades (densidade, resistência química, durabilidade, resistência mecânica, custo, etc.) tem-se mostrado como a melhor opção para profundidades de até 2.000 metros. Entretanto, a utilização de cabos poliméricos é uma tecnologia relativamente nova, pois as primeiras instalações realizadas pela Petrobras iniciaram a partir de 1997. Desde lá, muitos testes e simulações foram realizados para avaliar e confirmar o comportamento, durabilidade e segurança destes cabos. Porém, poucas informações estão disponíveis na literatura, a respeito do real comportamento de cabos que estiveram ancorados no ambiente marinho, por diferentes períodos de tempo. Dessa forma, esta dissertação tem como objetivo fornecer mais dados, a respeito da variação das propriedades de fibras constituintes de cabos de ancoragem de poliéster. Para tal, foram caracterizadas fibras virgens, fibras ensaiadas mecanicamente para controle de qualidade e fibras de cabos submersos por 3,5 e 7,0 anos. Os ensaios e as análises apresentados foram realizados para avaliar propriedades óticas (cor, brilho e opacidade), físicas (densidade linear e morfologia), térmicas (grau de cristalinidade, estabilidade térmica, etc.), químicas (composição), mecânicas (alongamento, tenacidade, módulo inicial e força de ruptura) e reológicas (viscosidade e massa molar) dos filamentos. Baseado nos resultados obtidos, pode se verificar alteração na cor (amarelamento) e aumento do brilho, opacidade, estabilidade térmica, grau de cristalinidade, viscosidade e da massa molar dos filamentos ancorados por longos períodos de tempo. Entretanto, embora haja vestígios de degradação nestas fibras, não se observou variação significativa na força necessária para rompê-las. Contudo, estas apresentaram um menor módulo inicial, alongamento e tenacidade de ruptura. / With the advent of floating platforms arranged on water in deeper depths, the development of lighter, durable and economically viable mooring lines, were and have been developed, being the polymeric materials the most promising. The polyester, due to an excellent combination of properties (density, chemical resistance, durability, strength, cost, etc.), has been considered as the best option for depths up to 2,000 meters. However, the use of polymeric cables is a relatively new technology, since the first installations performed by Petrobras took place in 1997. Since then, many simulations and tests were performed to evaluate and confirm the performance, durability and safety of such cables. Nevertheless, few information are available in the literature regarding the actual behavior of cables, that were anchored in the marine environment, for different periods of time. Thus, this dissertation aims to provide more data about the variation of the properties of fibers, which are the constituent of polyester anchoring cables. In order to achieve the goal of this dissertation, virgin fibers, mechanically tested for quality control and fiber cables submerged by 3.5 and 7.0 years were characterized. Tests and analyzes presented were conducted to evaluate optical properties (color, brightness and opacity), physical (linear density and morphology), thermal (degree of crystallinity, thermal stability, etc.), chemical (composition), mechanical (stretching, tenacity, initial modulus and breaking strength) and rheological properties (viscosity and molar mass) of filaments. Based on the obtained results, it was possible observe change in color, brightness, opacity, thermal stability, degree of crystallinity, viscosity and molar mass of filaments. However, although there are traces of degradation in the fibers, no significant variation was observed in the force required to break them. On the other hand, the fibers had a lower initial modulus, breaking elongation and toughness.

O P3HB é um tipo de poliéster sintetizado por bactérias como reserva de carbono e energia, e mobilizado na escassez destes. Um estudo com mutantes de Burkholderia sacchari, indicou o envolvimento de PhaZa1 e LonA na mobilização de P3HB. Este estudo avaliou o papel de PhaZa1 e LonA neste processo. A complementação heteróloga dos mutantes de B. sacchari, a partir dos genes phaZa1 e lonA de Ralstonia eutropha, restabeleceu a capacidade de mobilização dessas cepas, confirmando o envolvimento de seus produtos no processo. A partir de cepas recombinantes de Escherichia coli, abrigando tanto os genes de acúmulo de P3HB como de mobilização de R. eutropha, obteve-se cepas abrigando os genes phaZa1 e lonA isoladamente e outra abrigando os dois genes simultaneamente. Quando separados, tanto phaZa1 quanto lonA, não apresentaram papel significante na mobilização porém, quando os dois genes são expressos simultaneamente, as taxas de mobilização atingem mais de 50%, indicando que deva ter uma interação entre PhaZa1 e LonA para que o processo de mobilização seja efetivo. / The P3HB is a type of polyester synthesized by bacteria like carbon and energy source, and is mobilizated when there is a shortage of these. A study with mutants of Burkholderia sacchari, showed the involvement of PhaZa1 and LonA in mobilization of P3HB. The present study evaluated the role of PhaZa1 and LonA in this process. The heterologous complementation of mutants of B. sacchari, with phaZa1 and lonA genes from Ralstonia eutropha, reestablished the mobilization capacity in these strains, confirming the involvement of their products in this process. From the recombinant strain of Escherichia coli, harboring accumulation and mobilization genes from R. eutropha, we obtained strains harboring phaZa1 and lonA genes singly and another harboring both genes simultaneously. When expressed singly, both phaZa1 as lonA, had no significant role in mobilization but, when both genes were expressed simultaneously, the rates of mobilization reached more than 50%, appointing that an interaction must occur between PhaZa1 and LonA for the mobilization process to be effective.

Diploma thesis is focused on production technology of the glass fibre polyester part. It introduces characteristics of the composite materials and their dividing by the reinfocement geometry, reinforcement dimensions, reinfocement material and matrix materiál. In the final chapters thesis describes production technologies and proces of launching new part from 3D data to data and drawings of the mould including creation of the technological process.

The diploma thesis presents the usability of a new thermosetting material BMC for the construction of a car headlight. In the theoretical part there are described headlights, basic characteristics and properties of plastics focussing on polymer composite materials and material testing. The practical part deals with the processing of test samples for mechanical testing by compression moulding and also with the production of real samples of reflectors and carrier frames by injection moulding. The evaluation is based on comparison of the results of the performed tests of alternative material and the currently used BMC TETRADUR TD 492/2 in HELLA Autotechnik Nova s.r.o. Basic physical-mechanical properties such as strength, stiffness, toughness and hardness are tested and monitored. The reflectors and carrier frames are assembled into the headlight and then tested according to legal and customers´ requirements for climate and vibration resistance and photometry.

This master’s thesis focuses on biodegradation of polyhydroxybutyrate (PHB) and polylactic acid (PLA). The theoretical part discusses an origin, properties and applications of investigated biopolyesters, and so the enzymology of their biodegradation. The experimental part deals with biodegradation of these polymers in liquid medium using several pure thermophilic bacteial strains and controlled composting of these bioplastics. Amongst six tested thermophilic bacterial strains only one showed PHB-biodegradation activity – strain Schlegelella thermodepolymerans. No degradation degree of amorphous or semi-crystalline PLA was observed. Mainly disintegration of both forms of PLA articles was observed in compost environment, thus the abiotic mechanism of its decomposition was indicated. After 4 weeks of composting, the relative weight loss of 99 % and 63 % was detected in amorphous and semi-crystalline PLA respectively. On the contrary, the weight loss of PHB after 4 weeks of composting reached 36 %, moreover, a half decrease of molar mass was observed using SEC. The surface erosive mechanism of PHB-biodegradation was stated using SEM. By monitoring of esterase, lipase and protease activities, no influence on the compost by polymer presence was concluded at statistical significance.

No description available.

No description available.

The diploma thesis is aimed at an influence of surface modifications of fibrous reinforcements on mechanical properties at the fiber-matrix interface in fiber reinforced composites. Glass fibers were used as reinforcements and polyester resin was the matrix. The sample of composite consisted of polymer matrix in a form of cylindrical body placed on bundle of glass fibers. The design of the sample was constructed with respect to results of Finite Element Analysis (FEA). The tensile test using a materials testing machine (Zwick) was employed to evaluate adhesion at the fiber-matrix interface. Untreated glass fibers, fibers with commercial sizing, and fibers modified by deposition of plasma polymer film using Plasma-Enhanced Chemical Vapor Deposition (PECVD) at different deposition conditions were used for fabrication of composite samples. The fibers and composite samples were analyzed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM).

The textile industry is developing at a fast pace, and is constantly changing. It is constantly evolving new methods for recycling and further research is important for future needs. The ability to recycle a textile blended material is a step towards a more sustainable industry. There are however different difficulties around the various processes that have to be removed for recycling. The purpose of the study is to find methods for removing dyes from polyester and cotton blended textile waste for recycling. To investigate the subject, a literature study combined with interviews with experts was performed. The results of the study shows that it is possible to remove dye from cotton and polyester individually. To remove dye from cotton chlorine and hydrogen peroxide are used. Another method is to use a reducing agent hydrosulphite and after use together with lye. There are several ways to remove colour from polyester, although it will almost always have a residue of colour left. One can either melt the pigment into the fibre by using heat. Another method is to use chemicals which increase the amorphous areas in the fibres and the colour will be penetrated. Finally, when investigating a method for removing dye from a polyester and cotton textile blend. The study has highlighted the need of developing new methods without destroying the quality of the fibres. By this study it has been concluded removing dye from fibres are difficult but can be achieved with certain chemicals and processes. It is concluded in the study, removing dye from polyester and cotton individually can be succeed. However, removing colour from a blended fabric is rather difficult. The study has focus on discussing the difficulties when decolouring a blended textile.

The production of textiles, focusing on cotton and polyester, carries with it major environmental concerns such as significant water and chemical use as well as the use of non-renewable resources. Measures need to be taken to decrease those environmental burdens. The present study investigates four different recovery techniques in terms of specific environmental factors. The investigated recovery methods are the Re:newcell method, polyester recycling, textile to insulation material and biogas production from the digestion of textile waste. Incineration is also included as a reference alternative. Waste flows in Sweden are estimated through a literature review of conducted waste analyses and estimations as to the amount of secondary product that can be produced from that input are duly made. Further, the environmental implications of three potential locations for a sorting facility are investigated. Converting cotton into biogas was found to be an unrealistic approach since it is economically inviable and little or no energy is actually gained when transportation costs are taken into consideration. Further studies on the benefits and costs of recycling cotton into insulation material are needed. The unavoidable transportation related to collection, sorting and recycling are not to be underestimated and could in some cases hinder future environmental improvements.  Finally, the study found that fiber material recycling is the only treatment method that has the potential to decrease the environmental burdens related to primary production although, despite the fact it requires the most water and chemicals. However, the data reliability in the current study is a matter of concern and further research in the form of standardized data collection and the use of analytical and strategic tools in further assessments is recommended. Although the recovery of textile material is crucial for decreasing the environmental burdens from primary production of textiles, the work in preventing textile waste is even more vital. In the long run, the prevention of waste is far more important as recovery processes demands their own share of resources. / Den primära produktionen av textilier för med sig enorma miljömässiga påfrestningar. Omfattande mängder kemikalier och vatten samt icke-förnybara resurser används vid tillverkningen av bomull och polyester. Det är nödvändigt att vidta åtgärder för att minska dessa negativa effekter på miljön. Denna studie syftar till att undersöka fyra olika återvinningstekniker för textilt avfall med fokus på bomull och polyester. Förbränning med energiutvinning inkluderas som ett referensfall och återvinningsteknikerna jämförs med hjälp av utvalda miljöfaktorer. De återvinningstekniker som jämförs är Re:newcells metod för återvinning av bomull (och andra cellulosa material) till viskosfiber, kemisk polyesteråtervinning, återvinning av bomull till isoleringsmaterial för byggnader samt rötning av bomullstextilier för utvinning av biogas. Avfallsströmmarna i Sverige uppskattas med hjälp av litteraturstudier av framförallt genomförda plockanalyser. Alla faktorer jämförs med avseende på 1 ton blandat textilavfall från hushåll i Sverige och hur mycket av det som kan användas som potentiell råvara i återvinningsprocesserna. Vidare undersöks även de miljömässiga effekterna som uppstår vid transport av det textila avfallet till en sorteringsanläggning och till återvinnigsanläggningar. Tre potentiella placeringar av sorteringsanläggningen undersöks: Stockholm, Vänersborg och Wolfen, Tyskland. Studien fann att endast fibermaterialåtervinning har möjlighet att motverka de miljömässiga påfrestningarna från primärproduktionen även om de också innebär den största användningen av resurser såsom vatten och kemikalier. Rötning av bomull till biogas anses vara ett orealistiskt alternativ då metoden är ekonomiskt oförsvarbar och lite eller ingen energi egentligen utvinns när man inkluderar de nödvändiga transporterna. Vidare studier behövs för att uppskatta nyttan och kostnaderna för återvinning av bomull till isoleringsmaterial. De transporter som oundvikligt behövs vid återvinning pga. insamling, sortering och återvinning bör inte underskattas och kan i vissa fall förhindra att miljönyttan ökar. Resultaten i studien bör däremot användas kritiskt då tillförlitligheten i det data som har använts i vissa fall kan ifrågasättas. Detta beror på att många antaganden och uppskattningar har gjorts pga. brist på data av sekretesskäl. Mer forskning och undersökningar rekommenderas i form av standardiserade metoder för plockanalyser av textilt avfall. Användningen av analytiska och strategiska verktyg såsom LCA och EIA/SEA rekommenderas för att ta hänsyn till alla intressenter vad gäller end-of-life för textilt avfall. Fastän återvinning är en nödvändig del i arbetet att minska på de miljömässiga påfrestningarna som primärproduktion bidrar till är det ännu viktigare att arbeta med åtgärder för att minska avfallet. Återvinning kräver sin andel resurser i from av energi, vatten och kemikalier bland annat.