Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-20T22:32:00Z No. of bitstreams: 1 IsabelCavalcantiCabral_DISSERT.pdf: 3050113 bytes, checksum: 383bcdc049daf672f9e95cb2602b2eb2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-23T22:39:14Z (GMT) No. of bitstreams: 1 IsabelCavalcantiCabral_DISSERT.pdf: 3050113 bytes, checksum: 383bcdc049daf672f9e95cb2602b2eb2 (MD5) / Made available in DSpace on 2017-02-23T22:39:14Z (GMT). No. of bitstreams: 1 IsabelCavalcantiCabral_DISSERT.pdf: 3050113 bytes, checksum: 383bcdc049daf672f9e95cb2602b2eb2 (MD5) Previous issue date: 2016-08-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Atualmente vem crescendo a necessidade de aproveitamento dos res?duos gerados pela popula??o, como forma de criar materiais alternativos e de baixo custo, contribuindo assim para preserva??o do meio ambiente e aproveitamento dos recursos naturais. A fabrica??o de comp?sitos refor?ados com fibras vegetais e matriz polim?rica, tem sido uma alternativa para as ind?strias que buscam o aproveitamento de res?duos. O objetivo do presente trabalho foi desenvolver um comp?sito polim?rico com rejeito de polietileno como matriz e carga do p? da casca da semente da planta Sombreiro (Clitoria fairchildiana) nas propor??es de 2,5% e 5%, mostrando que pol?meros p?s consumo podem ser novamente aproveitados. As misturas pol?mero/carga foram produzidas atrav?s de uma extrusora, e em seguida os corpos de prova foram moldados por inje??o. Para caracterizar o comp?sito foram realizadas an?lises t?rmicas, medida do ?ndice de fluidez, determina??o da densidade, ensaio de dureza Shore D, resist?ncia ? tra??o, resist?ncia ao impacto Izod, microscopia eletr?nica de varredura (MEV) e absor??o de ?gua. Para os resultados reol?gicos, a viscosidade do comp?sito PE_rec A (Polietileno com adi??o de 2,5% de carga) diminuiu, j? o PE_rec B (Polietileno com adi??o de 5% de carga) aumentou. A massa especifica se manteve constante para todas as amostras e concentra??es. Como esperado a dureza do comp?sito foi proporcional ao percentual de carga que foi acrescentado, j? na resist?ncia m?xima a tra??o o comp?sito PE_rec A obteve um valor 2,3% menor comparado ao PE_rec Puro, o ensaio de impacto Izod mostrou que o comp?sito PE_rec A apresentou 444,30 J/m de energia absorvida durante o ensaio. Na an?lise por MEV foram observados a presen?a de vazios na microestrutura do material e a falta de ades?o matriz/carga em algumas regi?es do comp?sito polim?rico. O ensaio de absor??o de ?gua mostrou que para as duas concentra??es de carga natural o p? se mostrou n?o muito hidrof?lico. Com isso os resultados obtidos mostraram que o Polietileno reciclado pode ser processado novamente e o acr?scimo de carga ao comp?sito promoveu um ganho de economia de material sint?tico. / Currently it has increased the need for recovery of waste generated by the population as a way to create alternative and low-cost materials, thus contributing to preserving the environment and use of natural resources. The manufacture of composites reinforced with natural fibers and polymer matrix, has been an alternative for industries seeking the recovery of waste. The aim of this study was to develop a polymeric composite tailings as polyethylene matrix and load powder seed bark Sombreiro plant (Clitoria fairchildiana) in the proportions of 2.5% and 5%, showing that post-consumer polymers can be again used. Mixtures polymer / load were produced through an extruder, and then the samples were injection molded. To characterize the composite were performed thermal analysis, measurement of flow rate, density determination, hardness testing Shore D, tensile strength, Izod impact strength, scanning electron microscopy (SEM) and water absorption. For the rheological results, the viscosity of the composite PE_rec (polyethylene with addition of 2.5% load) has decreased since the PE_rec B (Polyethylene with addition of 5% load) has increased. The bulk density was kept constant for all samples and concentrations. As expected the hardness of the composite was proportional to the load percentage that has been added since the maximum tensile strength the PE_rec The composite obtained a 2.3% lower compared to PE_rec Pure, the Izod impact test showed that the composite PE_rec The presented 444.30 J/m energy absorbed during the test. In the analysis by SEM were observed the presence of voids in the microstructure of the material and the lack of adhesion matrix / load in some regions of the polymer composite. The water absorption test showed that for both natural load concentrations powder proved not very hydrophilic. Thus the results showed that the recycled polyethylene can be processed again and the composite load increase promoted a gain of synthetic material economy.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T19:31:01Z No. of bitstreams: 1 FernandaAlvesRibeiro_TESE.pdf: 4972549 bytes, checksum: 0745d78d97b0e53b086d596f53414354 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-10T23:32:57Z (GMT) No. of bitstreams: 1 FernandaAlvesRibeiro_TESE.pdf: 4972549 bytes, checksum: 0745d78d97b0e53b086d596f53414354 (MD5) / Made available in DSpace on 2017-03-10T23:32:57Z (GMT). No. of bitstreams: 1 FernandaAlvesRibeiro_TESE.pdf: 4972549 bytes, checksum: 0745d78d97b0e53b086d596f53414354 (MD5) Previous issue date: 2016-10-11 / O consumo esmagador de Polietileno tereftalado (PET) grau garrafa constitui cap?tulo ? parte entre as resinas produzidas no Brasil. Embora o pa?s consiga reciclar mais da metade da produ??o de PET, ainda ? muito elevado o volume deste material em forma de garrafas. Salienta-se que, apesar do benef?cio da resina PET poder ser utilizada em in?meras aplica??es e sob diversos processos, ? necess?rio desenvolver alternativas de seu reuso na via de reciclagem. Nesta vertente, o objetivo da pesquisa foi avaliar a aplica??o do tecido de pet, oriundo do processo de reciclagem das garrafas, como refor?o de comp?sitos polim?ricos. Para tanto, na metodologia utilizada, ap?s a preliminar caracteriza??o do tecido de pet via ensaios t?xteis (Determina??o de gramatura; Resist?ncia ? propaga??o ao rasgo; Resist?ncia ? tra??o e alongamento), confeccionou-se laminados comp?sitos polim?ricos com matriz ep?xi e diferentes fra??es de tecido para a verifica??o e an?lise de suas principais propriedades f?sico-qu?micas, mec?nicas e t?rmicas. Os seguintes ensaios foram realizados nos corpos de prova de resina e laminado comp?sito: Densidade; Absor??o de ?gua; Teor de umidade; Tra??o uniaxial; Flex?o em tr?s pontos; Compress?o; Dureza; TG; DMA e An?lise de fratura. A an?lise dos resultados evidenciou que o incremento de camadas de tecido propicia ao comp?sito o aumento nas resist?ncias ? tra??o e ? compress?o; al?m do que, eleva a rigidez viscoel?stica do material, ao passo que diminui a resist?ncia ? flex?o. Observou-se tamb?m que as camadas de tecido de PET diminuem o teor de umidade do comp?sito, bem como a sua capacidade de absor??o de ?gua. Contudo, as propriedades Dureza e Densidade n?o apresentaram varia??o significativa com a inclus?o do tecido de PET. A configura??o P90, com o m?ximo teor de tecido de PET no laminado, exprimiu-se como a de melhor desempenho frente aos ensaios realizados. Deste modo, a utiliza??o do tecido PET evidencia aspectos atraentes para as iniciativas empresariais do setor. A composi??o P90, como refor?o de comp?sito polim?rico, foi a que apresentou melhor resultado. Esse material tr?s reflexos socio-econ?micos diretamente relacionados com a melhoria da qualidade de vida da popula??o, gera??o de renda, economia de recursos naturais e atenua??o de problemas ambientais. / There is no doubt whatsoever that the widest consumption of polyethylene terephthalate (PET) bottle grade is a unique chapter among the resins produced in Brazil. Although the country is able to recycle more than a half of all PET production, the number of such material for bottle fabrication is still very high. It is important to remark that, though all benefits of PET resin uses in uncountable applications and under many processes; alternatives to its reuse throughout recycling dynamics must be developed. Thus, this work aims at evaluating the application of PET fabric coming from the process of bottle recycling polymeric composite reinforcements. In order to do so, after a preliminary characterization of the PET fabric by textile tests (Grammage determination; Tear propagation resistance; Tensile strength and elongation resistance), laminated polymeric composite with epoxy matrix as well as different fractions of fabric for checking and analysis of their main physicochemical, mechanical and thermal properties were engendered. The following tests were performed with the resin and with laminated composite: Density, Water absorption; Moisture content; Uniaxial tensile; Three point flexural test; Compression; Hardness; TG; DMA and Fracture analysis. By analyzing the results, it was noticed that the increase of fabric layers provide a resistance and compression gain to the composite, and it also increases the material viscoelastic stiffness, at the same time as its flexural strength is diminish. It was also noticed that its water absorption capacity was diminished. Nevertheless, its hardness and density properties did not present meaningful variation with the PET addition. The P90 setting with the highest content of PET fabric in the laminate presented itself as having the best results in the tests. Therefore the use of PET fabric presents attracting aspects to entrepreneurship. P90 configuration used as polymeric composite reinforcements were the one to present the best results. Such material brings socio-economical reflexions directly linked to the improvement of livelihood, natural resources economy and offset environment problems.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-20T20:04:27Z No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-22T20:17:43Z (GMT) No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) / Made available in DSpace on 2017-03-22T20:17:43Z (GMT). No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) Previous issue date: 2017-01-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A utiliza??o de res?duos industriais est? em evid?ncia na atualidade, principalmente em fun??o da quest?o ambiental. Nos ?ltimos anos in?meros comp?sitos foram obtidos e estudados, com a utiliza??o de res?duos e fibras vegetais, desmistificando o conceito de que um material s? pode ser chamado de comp?sito se a carga for de refor?o. Obteve e estudou-se um comp?sito de matriz de resina poli?ster (ortoft?lica e tereft?lica) e carga de enchimento de raspa de madeira produzida em marcenarias. Foram estudados os processos de obten??o dos comp?sitos e a caracteriza??o de propriedades mec?nicas, t?rmicas e f?sicas nas amostras dos comp?sitos com fra??o m?ssica de 10, 20 e 30%, para tr?s diferentes granulometrias, totalizando seis formula??es para porcentagens. Por?m, foi escolhida a formula??o com 20%, pois com essa porcentagem j? tinha atingido a satura??o da mistura. Os ensaios realizados foram de tra??o, flex?o, t?rmico, absor??o de ?gua, densidade, biodegrada??o, degrada??o ambiental e MEV. Os comp?sitos obtidos, em todas as formula??es estudadas, apresentaram resist?ncia mec?nica inferior a da matriz, por?m n?o inviabilizou sua utiliza??o para aplica??es onde n?o s?o requeridos significativos esfor?os. Em termos de resist?ncia t?rmica o comp?sito proposto foi competitivo com a resina matriz, tendo comportamento um pouco inferior. Como esperado os comp?sitos apresentaram maiores ?ndices de absor??o de ?gua quando comparados ?s matrizes polim?ricas. A densidade aparente dos comp?sitos n?o apresentou varia??o significativa em rela??o ?s matrizes utilizadas. Demonstrou-se, portanto, que os res?duos agregados ? resina t?m a fun??o de carga de enchimento. O comp?sito foi utilizado para a fabrica??o de tampos de bancos, demonstrando-se sua viabilidade de aplica??o na fabrica??o de estruturas apara baixas solicita??es mec?nicas. / The use of industrial waste is nowadays evident, especially in the environmental issue. In recent years, the results have been obtained with the use of waste and vegetable fibers, the dismemberment of the concept of a material can be called composite. A polyester resin composite (orthophthalic and terephthalic) composite and filler of wood produced in woodworking was obtained and studied. The processes of obtaining composites and a characterization of mechanical, thermal and physical properties in composite samples with a more specific fraction of 10, 20 and 30% were studied for three different granulometries, totaling six formulations for percentages. However, a formulation with 20% was chosen, because with that percentage already had a saturation of the mixture. The tests carried out for tensile, flexural, thermal, water absorption, density, biodegradation, environmental degradation and MEV tests. The composites obtained in all the studied formulations had lower mechanical resistance than the matrix, however it did not make it impossible to use them in applications where no significant efforts are required. In terms of thermal resistance or composite proposed to competitive with a resin matrix, having somewhat lower behavior. As expected the composites presented higher water absorption indices when compared to the polymer matrices. The apparent density of the composites does not present significant variation in relation to the used dimensions. It has been demonstrated, therefore, that the residues aggregated to the resin have a filling charge function. The composite was used for the manufacture of seat tops, demonstrating its feasibility of application in the fabrication of structures for low mechanical stresses.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-19T20:22:47Z No. of bitstreams: 1 JeronimoMailsonCiprianoCarlosLeite_TESE.pdf: 3038205 bytes, checksum: dd114b39d1209f01fe463b1a3b28b51f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-20T22:14:29Z (GMT) No. of bitstreams: 1 JeronimoMailsonCiprianoCarlosLeite_TESE.pdf: 3038205 bytes, checksum: dd114b39d1209f01fe463b1a3b28b51f (MD5) / Made available in DSpace on 2017-09-20T22:14:29Z (GMT). No. of bitstreams: 1 JeronimoMailsonCiprianoCarlosLeite_TESE.pdf: 3038205 bytes, checksum: dd114b39d1209f01fe463b1a3b28b51f (MD5) Previous issue date: 2017-06-30 / A utiliza??o de materiais comp?sitos para a constru??o civil tem sido objeto de estudo acad?mico em universidades e centros de pesquisa no Brasil e no mundo. Um dos elementos motivadores ? o d?ficit habitacional que os pa?ses principalmente do terceiro mundo enfrentam. No Brasil, entre 2010 e 2014, esse d?ficit alcan?a mais de 6,5 milh?es de moradias, em torno de 12 % dos domic?lios do pa?s. Esse trabalho apresenta um comp?sito que foi obtido a partir de res?duos gerados na ind?stria da constru??o civil (brita e cer?mica), res?duos de vidro gerados pela ind?stria vidraceira e elementos comuns em materiais da constru??o, tais como cimento, areia e ?gua. Esses res?duos causam grandes danos ao meio ambiente e s?o jogados nos aterros em grandes quantidades. O trabalho foca no uso de tr?s res?duos para a obten??o o comp?sito e na fabrica??o de dois tipos de blocos, um maci?o usado para piso e um vazado para ser usado em fechamentos verticais em edifica??es, podendo ser utilizados como alvenaria estrutural ou de veda??o. Utilizou-se doze formula??es, sendo duas delas servindo refer?ncia denominadas formula??es Padr?es, e posteriormente foram selecionadas as seis de melhores resultados mec?nico, incluindo uma padr?o com Cimento, Areia M?dia e ?gua. As formula??es escolhidas foram caracterizadas, determinando-se as resist?ncias ? compress?o axial e diametral, a absor??o de ?gua por capilaridade e imers?o total, a densidade e as propriedades t?rmicas. Foram confeccionados blocos com duas das formula??es do comp?sito de melhores resultados gerais utilizando formas especialmente fabricadas para este fim. Os resultados mais expressivos do comp?sito foram obtidos para a resist?ncia mec?nica ? compress?o que atingiu valor superior a 13 Mpa, absor??o de ?gua com resultados inferior a 7,5 %, Densidade inferior a 2,5 g/cm?, Condutividade com valores pr?ximos a 5 W/m.K e Difusividade inferior a 4 mm?/s. Estes resultados permitem que o comp?sito possa ser utilizado tanto na fabrica??o de blocos para alvenaria de veda??o quanto estrutural, tornando-o mais vers?til na ind?stria da constru??o civil. / The use of composite materials for civil construction has been the object of academic study in universities and centers of research in Brazil and worldwide. One of the motivating factors is the housing deficit that the countries of the third world are facing. In Brazil, between 2010 and 2014, this deficit reaches more than 6.5 million homes, around 12% of the country's households. This work presents a composite that was obtained from waste generated in the construction industry (gravel and ceramics), glass waste generated by the glazing industry and common elements in construction materials, such as cement, sand and water. These wastes cause great damage to the environment and are disposed of in landfills in large quantities. The work focuses on the use of three residues to obtain the composite and in the manufacture of two types of blocks, a solid one used for floor and one to be used in vertical closings in buildings, being able to be used as structural masonry or of sealing. Twelve formulations were used, two of them serving reference denominated Standard formulations, and later were selected the six of better mechanical results, including a standard with Cement, Average Sand and water. The chosen formulations were characterized, determining the resistance to axial and diametrical compression, water absorption by capillarity and total immersion, density and thermal properties. Blocks were made with two of the best overall composite formulations using specially fabricated forms for this purpose. The most expressive results of the composite were obtained for the mechanical resistance to compression reaching a value higher than 13 MPa, absorption of water with results lower than 7.5 %, Density less than 2.5 g/cm?, Conductivity with values close to 5 W/m.K and diffusivity less than 4 mm?/s. These results allow the composite to be used both in the manufacture of structural and masonry blocks, making it more versatile in the construction industry.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-19T20:22:47Z No. of bitstreams: 1 PedroHenriqueDeAlmeidaVarela_TESE.pdf: 3830218 bytes, checksum: 005615173861fc156d52b9e540b62bb4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-20T22:45:54Z (GMT) No. of bitstreams: 1 PedroHenriqueDeAlmeidaVarela_TESE.pdf: 3830218 bytes, checksum: 005615173861fc156d52b9e540b62bb4 (MD5) / Made available in DSpace on 2017-09-20T22:45:54Z (GMT). No. of bitstreams: 1 PedroHenriqueDeAlmeidaVarela_TESE.pdf: 3830218 bytes, checksum: 005615173861fc156d52b9e540b62bb4 (MD5) Previous issue date: 2017-07-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A Fabrica??o de novos materiais comp?sitos ? uma alternativa para substituir materiais convencionais, nesse intuito foi obtido e estudado a viabilidade do uso do Tecido Plano de Juta (TPJ) e tecido de fibra de vidro (TFV) em um comp?sito h?brido de matriz de resina poli?ster ortoft?lica. O processo de obten??o do comp?sito foi testado em rela??o ao n?mero m?ximo de camadas que poderia ser utilizado, sem comprometer a sua processabilidade e a fabrica??o dos corpos de prova (CPs) em molde compressivo. Foram escolhidas e testadas duas configura??es, h?bridas e n?o h?bridas, com 4, 6, 8 e 10 camadas de tecido plano de juta mais a resina ortoft?lica e 4, 6, 8 e 10 camadas de tecido plano de juta intercalados com o tecido de fibra de vidro mais a resina ortoft?lica. O comp?sito em suas duas configura??es e v?rias formula??es foi caracterizado para a determina??o de suas principais propriedades atrav?s das analises de tra??o, flex?o, impacto, densidade, absor??o de umidade, condutividade t?rmica, envelhecimento, MEV, DRX e FRX. No comp?sito proposto o TPJ e o TFV tiveram fun??o de carga de refor?o, com predomin?ncia para o TFV uma vez que todas as formula??es estudadas para o comp?sito h?brido apresentaram resist?ncia mec?nica superior ? da resina. A configura??o com 10 camadas de tecido de juta e 10 camadas de tecido de vidro 10TJV foi ? configura??o de melhor resultado de resist?ncia ? tra??o, ? flex?o e ao impacto. O melhor desempenho do comp?sito h?brido em rela??o ? resina foi ? resist?ncia ao impacto chegando a alcan?ar valores bem superiores, na ordem de 1000% maior em rela??o ? mesma. As propriedades t?rmicas do comp?sito h?brido foram competitivas com as da resina ortoft?lica, trazendo boas possibilidades para aplica??es t?rmicas. O MEV evidenciou que houve ader?ncia entre o TPJ, o TFV e a resina para todas as configura??es, por?m ocorreram fissuras, vazios e desprendimento de feixes de fibra. O comp?sito proposto apresentou viabilidade para a fabrica??o de prot?tipos solares e e?licos, como foi demonstrada pela obten??o de uma p? a ser usada em aerogeradores do tipo darrieus, e de uma par?bola que foi utilizada em um fog?o solar multifocal. / The manufacture of new composite materials is a cheaper alternative to replace conventional materials, in order to obtain the feasibility of using Jute Plane Tissue (TPJ) and fiberglass fabric (TFV) in a hybrid matrix composite Orthophthalic polyester resin. The process of obtaining the composite was tested in relation to the maximum number of layers that could be used, without compromising its processability and the manufacturing of the specimens (CPs) in compressive mold. Two hybrid and non-hybrid configurations were chosen and tested with 4, 6, 8 and 10 layers of jute flat fabric plus orthophthalic resin and 4, 6, 8 and 10 layers of jute flat fabric interspersed with the fiber fabric Glass plus orthophthalic resin. The composite in its two configurations and several formulations was characterized for the determination of its main properties through tensile, flexural, impact, density, moisture absorption, thermal conductivity, aging, MEV, DRX and FRX analyzes. In the proposed composite, the TPJ and TFV had a reinforcing load function, with a predominance of TFV, since all the formulations studied for the hybrid composite presented superior mechanical resistance to the resin. The configuration with 10 layers of jute fabric and 10 layers of glass 10TJV fabric was the configuration of best result of tensile, flexural and impact resistance. The best performance of the hybrid composite in relation to the resin was to the impact resistance reaching well higher values, in the order of 1000% greater in relation to the same. The thermal properties of the hybrid composite were competitive with those of the orthophthalic resin, giving good possibilities for thermal applications. The MEV showed that there was adhesion between the TPJ, the TFV and the resin for all configurations, but cracks, voids and fiber bundle detachment occurred. The proposed composite presented viability for the production of solar and wind turbine prototypes, as demonstrated by obtaining a shovel to be used in darrieus type wind turbines, and a parabola that was used in a multifocal solar cooker.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-02T23:44:17Z No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-09T20:53:35Z (GMT) No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) / Made available in DSpace on 2017-10-09T20:53:35Z (GMT). No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) Previous issue date: 2017-07-21 / O descarte de pneus no meio ambiente na forma de res?duo vem causando grandes problemas e impactos ambientais. Sendo assim, este trabalho apresenta a obten??o e estudo da caracteriza??o de um material comp?sito, voltado para a fabrica??o de um absorvedor de impacto de para-choque automotivo. Esse material foi fabricado com resina matriz de poliuretano (PU) ? base de petr?leo e carga de res?duos de pneu, oriundos do processo de recauchutagem. Para tanto, cinco formula??es com diferentes percentuais de res?duo de pneu (0%, 30%, 45%, 70% e 100%) foram obtidas e caracterizadas no que se refere ?s suas propriedades mec?nicas, t?rmicas, de absor??o de umidade, densidade e degrada??o pela sua exposi??o ?s intemp?ries. Al?m disso, foram realizados os ensaio de Microscopia Eletr?nica de Varredura (MEV) e Espectroscopia de Energia Dispersiva (EDS) no material para que se pudesse observar sua microestrutura (distribui??o de res?duos na matriz, vazios, imperfei??es e impurezas) e identificar os elementos qu?micos presentes, respectivamente. Como resultado geral, os comp?sitos apresentaram um aumento na sua densidade conforme se aumentava o percentual de res?duo de pneu, assim como a condutividade t?rmica. Quanto ?s propriedades mec?nicas, a formula??o que teve maior resist?ncia ? tra??o, flex?o e compress?o foi a de 45% e a de maior resist?ncia ao impacto foi a de 100%. Com rela??o ? resist?ncia ao envelhecimento a formula??o de 100% foi a que obteve melhor desempenho. Foi fabricado um absorvedor de para-choque com a formula??o de 45% que apresentou um acr?scimo de massa de 28,03%, demonstrando-se a viabilidade de fabrica??o desse componente automotivo. / The disposal of tires in the environment in the form of waste is causing major problems and environmental impacts. Thus, this work presents the study and the characterization of a composite material, aimed at the manufacture of an automotive bumper absorber. This material was manufactured with petroleum based polyurethane (PU) matrix resin and tire residue loading, from the retread process. Five formulations with different percentages of tire residue (0%, 30%, 45%, 70% and 100%) were obtained and characterized with respect to their mechanical and thermal properties, moisture absorption, density and degradation by exposure to the elements. Scanning Electron Microscopy (SEM) and Dispersive Energy Spectroscopy (EDS) tests were also performed on the material so that its microstructure could be observed (distribution of residues in the matrix, voids, imperfections and impurities) and to identify the chemical elements present , respectively. As a general result, the composites presented an increase in their density as the percentage of tire residue increased, as well as the thermal conductivity. As for the mechanical properties, the formulation with the highest tensile, flexural and compression strength was 45% and the one with the highest impact strength was 100%. Regarding the resistance to aging the formulation of 100% was the one that obtained better performance. A bumper absorber was manufactured with the 45% formulation, which presented a mass increase of 28.03%, demonstrating the feasibility of manufacturing this automotive component.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-18T20:27:51Z No. of bitstreams: 1 RudsonDeSouzaLima_TESE.pdf: 3299242 bytes, checksum: 3e308727599cf78da8ad994be49620ac (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-23T23:00:51Z (GMT) No. of bitstreams: 1 RudsonDeSouzaLima_TESE.pdf: 3299242 bytes, checksum: 3e308727599cf78da8ad994be49620ac (MD5) / Made available in DSpace on 2017-10-23T23:00:51Z (GMT). No. of bitstreams: 1 RudsonDeSouzaLima_TESE.pdf: 3299242 bytes, checksum: 3e308727599cf78da8ad994be49620ac (MD5) Previous issue date: 2017-06-05 / Diante da realidade mundial de preserva??o ambiental, da necessidade de reaproveitamento de insumos, redu??o de custos e melhoramento de propriedades, tem-se desenvolvido muitas tecnologias que atendam a uma s?rie desses fatores e, se poss?vel, a todos. Nesse sentido, os materiais comp?sitos assumem um papel de destaque nesse desenvolvimento de novos materiais. O PET (Polietileno tereftalato) tem sido muito utilizado pela ind?stria mundial em v?rias aplica??es, onde a principal dessas ? a produ??o de embalagens de produtos de aliment?cios, em que as ind?strias de refrigerantes s?o os grandes consumidores desse produto. J? na linha de fibras naturais, existe uma vasta quantidade de op??es de uso em aplica??es de engenharia (Sisal, carna?ba, algod?o, pia?ava, etc.). Diante do exposto, esse trabalho visa ? produ??o, caracteriza??o (Mec?nicos, t?rmicos e f?sicos) e compara??o de uma s?rie de configura??es de materiais comp?sitos com uma matriz polim?rica (Ep?xi) com refor?o de PET p?s-consumo e pia?ava (Resina ep?xi para refer?ncia; ep?xi com fibras de PET; ep?xi com fibras de pia?ava; e comp?sito h?brido). Os comp?sitos foram produzidos com fibras bidirecionais em forma de tecido, as fibras tinham espa?amento entre elas de 1 cm. Os materiais refor?ados promoveram aumento de algumas propriedades, como flex?o, que apresentou um incremento de cerca de 25% na tens?o m?xima admiss?vel do material. Observou-se que a ordena??o das fibras em sentido unidirecional pode melhorar as resist?ncias mec?nicas do comp?sito, isso porque, de forma geral, todas as rupturas dos ensaios ocorreram em uma sec??o de fragiliza??o provocada pelas fibras transversais aos esfor?os. Quando submetidos a esfor?os mec?nicos, o comp?sito com refor?o/carga de PET apresentou-se como a melhor configura??o, o qual apresentou um m?dulo de elasticidade em regime de flex?o 24% maior que a resina pura. J? em an?lise t?rmica, o comp?sito h?brido apresentou melhores caracter?sticas para isolamento t?rmico, visto que sua condutividade t?rmica reduziu em 2% quando comparado com o ep?xi puro. / Over the world reality of environment preservation, the necessity of reuse supplies, reduction of costs and improvement of properties, it has been developed many technologies that support a series of these factors and, if possible all of them. In this sense, the composite materials assume a special role in the growth of new materials. The PET (polyethylene terephthalate) has been utilized by worldwide industries in many different applications, from which the principal one of them is the packaging of food production, wherefrom the soft drink industries are the most substantial consumer of this product. As for natural fibers research line, there is a vast quantity of options for engineering application handling (Sisal, carnauba, cotton, piassava, etc.) In the face of what has been exposed, this research strives for the production, characterization (Mechanical, thermal and physical) and comparison of a series of configurations in the composite materials with a polymer matrix (Epoxy) with reinforcement of PET after consummation and piassava (epoxy resin for reference; enhancement resin with piassava fibers; and hybrid composite). The composites were produced with bidirectional fibers in a format of tissue, the fibers had spaces between them of 1 centimeter. The reinforced materials promoted increment of some properties, such as flection, that presented an enhancement of nearly 25% of maximum tension admitted in the material. It was observed however, that the ordination of the fibers in a unidirectional way might improve the mechanic resistance of the composite, that?s because, in general form, all the ruptures occur in one section of fragilization provoked by the transversal fibers to the reinforces. While submitted to mechanic reinforces, the composite with reinforce/charge of PET presented itself with an improved configuration, Which showed a modulus of elasticity in a regime of flexion 24% larger than the pure resin. As for the thermal analysis, the hybrid composite presented enriched characteristics for the thermal insulation, since its thermal conductivity reduced by 2% when compared to the pure epoxy.

Made available in DSpace on 2014-12-17T14:06:56Z (GMT). No. of bitstreams: 1 EugenioOO_DISSERT.pdf: 4689753 bytes, checksum: 3bf8e997d1b94d1858f0a0c5652f05b0 (MD5) Previous issue date: 2010-11-19 / Pipelines for the transport of crude oil from the production wells to the collecting stations are named production lines . These pipes are subjected to chemical and electrochemical corrosion according to the environment and the type of petroleum transported. Some of these lines, depending upon the composition of the fluid produced, may leak within less than one year of operation due to internal corrosion. This work aims at the development of composite pipes with an external protecting layer of high density polyurethane for use in production lines of onshore oil wells, meeting operational requirements. The pipes were manufactured using glass fibers, epoxy resin, polyester resin, quartz sand and high density polyurethane. The pipes were produced by filament winding with the deposition of high density polyurethane on the external surface and threaded ends (API 15 HR/PM-VII). Three types of pipes were manufactured: glass/epoxy, glass/epoxy with an external polyurethane layer and glass/epoxy with an intermediate layer of glass fiber, polyester, sand and with an external polyurethane layer. The three samples were characterized by Scanning Electronic Microscopy (SEM) and for the determination of constituent content. In addition, the following tests were conducted: hydrostatic test, instant rupture, shorttime failure pressure, Gardner impact, transverse stiffness and axial tension. Field tests were conducted in Mossor? RN (BRAZIL), where 1,677 meters of piping were used. The tests results of the three types of pipes were compared in two events: after two months from manufacturing of the samples and after nine months of field application. The results indicate that the glass/epoxy pipes with an intermediate layer of fiber glass composite, polyester e sand and with an external layer of high density polyurethane showed superior properties as compared to the other two and met the requirements of pressure class, axial tensile strength, transverse stiffness, impact and environmental conditions, for onshore applications as production lines / As tubula??es para transporte de petr?leo dos po?os de produ??o at? a esta??o coletora s?o denominadas de linhas de surg?ncia . Essas tubula??es est?o sujeitas ? corros?o qu?mica e eletroqu?mica, de acordo com o ambiente e os tipos de petr?leo. Algumas dessas linhas, a depender da composi??o do petr?leo produzido falham, ?s vezes, com menos de um ano de opera??o, devido ? corros?o interna severa. Este trabalho objetiva o desenvolvimento de tubula??o em comp?sito revestida externamente com poliuretano de alta densidade, para aplica??o em linhas de surg?ncia de po?os de petr?leo onshore e que atenda ?s exig?ncias operacionais. Neste desenvolvimento foram empregados fibra de vidro, resina ep?xi, resina poli?ster, areia quartzosa e poliuretano (PU) de alta densidade. Os tubos foram produzidos pelos processos de enrolamento filamentar com deposi??o de PU na superf?cie externa e extremidades com rosca moldada (API 15 HR e PM-VII). Foram produzidas tr?s concep??es de tubos: vidro/ep?xi sem revestimento, vidro/ep?xi revestido com poliuretano de alta densidade e vidro/ep?xi coberto por um composto de fibra de vidro, poli?ster e areia, revestido externamente com poliuretano de alta densidade. Amostras das tr?s concep??es foram caracterizadas atrav?s da t?cnica de Microscopia Eletr?nica de Varredura (MEV), da determina??o do teor de vidro e resina, dos ensaios de rigidez e tra??o axial e dos testes hidrost?ticos, ruptura instant?nea, press?o de curta dura??o e impacto Gardner. Essa nova tecnologia foi testada no campo de produ??o em Mossor? RN, nos quais foram instalados 1.677 metros de tubos. Assim, os resultados dos ensaios e testes das tr?s concep??es de tubos foram comparados entre si em dois eventos: ap?s dois meses da fabrica??o das amostras e ap?s nove meses da aplica??o dos tubos em campo. Os dados indicaram que o tubo em comp?sito vidro/ep?xi, poli?ster e areia, revestido externamente com poliuretano de alta densidade , apresentou melhores resultados quando comparado aos outros dois, podendo ser usado na ind?stria de petr?leo em aplica??es onshore , como uma alternativa para a aplica??o em linhas de surg?ncia, atendendo ?s exig?ncias de classe de press?o, resist?ncia ? tra??o axial, rigidez, impacto e intemp?ries

Made available in DSpace on 2014-12-17T14:07:03Z (GMT). No. of bitstreams: 1 LuandaGD_DISSERT.pdf: 2374976 bytes, checksum: 5b49cc11854aa2427f22f38d6ff109c2 (MD5) Previous issue date: 2012-08-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The study aimed at the treatment of attapulgite for the development and characterization of composite recycled low density polyethylene - PEBD_rec embedded with natural attapulgite - ATP_NAT, sifted - ATP_PN and attapulgite treated with sulfuric acid - ATP_TR in different compositions (1, 3 and 5%) and compared with the PEBD_rec. The atapulgitas, natural, screened and treated, were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and determining the area specific surface (BET). The composites were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), Xray diffraction (XRD), torque rheometry, scanning electron microscopy (SEM) and traction. The composite PEBD_rec / ATP (natural, sieved and treated) were produced by mixing in the molten state in a single screw extruder matrix wire with subsequent reprocessing matrix tape. It was found that the screening of attapulgite not reduce the quantity of quartz and the acid treatment completely extracted dolomite aggregate impurities of the channels attapulgite, and increase their surface area. The addition of attapulgite in PEBD_rec acts as a catalyst, reducing the thermal stability of the polymer. The increased concentration of attapulgite, increases resistance and reduces the elongation at break and modulus of elasticity of the composite PEBD_rec / attapulgite / O trabalho teve como objetivo o tratamento da atapulgita para o desenvolvimento e a caracteriza??o de comp?sito de polietileno de baixa densidade reciclado PEBD_rec incorporado com atapulgita natural ATP_NAT, peneirada ATP_PN e com atapulgita tratada com ?cido sulf?rico ATP_TR, em diferentes composi??es (1, 3 e 5%) e comparado com o PEBD_rec. As atapulgitas, natural, peneirada e tratada, foram caracterizadas por difra??o de raios X (DRX), fluoresc?ncia de raios X (FRX), an?lise granulom?trica, microscopia eletr?nica de varredura (MEV), espectroscopia de energia dispersiva (EDS) e determina??o da ?rea superficial espec?fica (BET). Os comp?sitos foram caracterizados por an?lise termogravim?trica (TG), calorimetria diferencial explorat?ria (DSC), difra??o de raios X (DRX), reometria de torque, microscopia eletr?nica de varredura (MEV) e tra??o. Os comp?sitos de PEBD_rec /ATP (natural, peneirada e tratada) foram produzidos por meio de mistura no estado fundido em uma extrusora monorosca com matriz de fio com posterior reprocessamento com matriz de fita. Verificou-se que o peneiramento da atapulgita n?o reduziu o teor de quartzo e que o tratamento ?cido extraiu completamente a dolomita, impureza agregada nos canais da atapulgita, al?m de aumentar sua ?rea superficial. A adi??o da atapulgita no PEBD_rec atua como catalisador, reduzindo a estabilidade t?rmica do pol?mero. O aumento da concentra??o de atapulgita aumenta a resist?ncia e reduz o alongamento na ruptura e o m?dulo de elasticidade do comp?sito PEBD_rec / atapulgita

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-16T20:26:43Z No. of bitstreams: 1 FlaviaSousaDeOliveira_DISSERT.pdf: 48913373 bytes, checksum: 8725e34968125209c5fa12e80d31bc55 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-18T21:45:29Z (GMT) No. of bitstreams: 1 FlaviaSousaDeOliveira_DISSERT.pdf: 48913373 bytes, checksum: 8725e34968125209c5fa12e80d31bc55 (MD5) / Made available in DSpace on 2016-08-18T21:45:29Z (GMT). No. of bitstreams: 1 FlaviaSousaDeOliveira_DISSERT.pdf: 48913373 bytes, checksum: 8725e34968125209c5fa12e80d31bc55 (MD5) Previous issue date: 2015-12-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A demanda por conforto ambiental em sistemas construtivos, no ?mbito da isola??o e conforto t?rmico, somada ao advento de novas leis que regulam os requisitos m?nimos de conforto, as exig?ncias dos consumidores pela ado??o de m?todos de produ??o mais ?limpos?, incentivaram o desenvolvimento do presente trabalho. O mesmo tem como objetivo caracterizar tecnologicamente as mat?rias-primas: res?duo termopl?stico de bot?o e res?duos de gesso para incorporar ao cimento, visando a produ??o de comp?sitos com propriedades de isola??o t?rmica: condutividade, difusividade, capacidade calor?fica e resistividade. As propriedades f?sicas, estruturais e morfol?gicas das mat?rias-primas foram investigadas atrav?s de an?lises de termogravimetria (TG), difra??o de raios X (DRX), fluoresc?ncia de raios X (FRX) e microscopia eletr?nica de varredura (MEV). Os resultados das an?lises indicaram caracter?sticas adequadas para a produ??o de comp?sito de matriz de cimento com adi??o de res?duos industriais termopl?sticos e res?duo de gesso, apresentando potencial de aplica??o destas mat?rias-primas em comp?sitos com propriedades de isola??o t?rmica. / The demand for environmental comfort in construction systems within the insulation and thermal comfort, plus the advent of new laws regulating the minimum requirements of comfort, disposal of solid industrial waste, construction waste, the requirements of consumers by adopting construction methods "cleaner", encouraged the development of this work. Aims technologically characterize the composite proposed in three types of samples (10%, 30% and 50% of thermoset plastic industrial waste) and raw materials: gypsum waste, cement and plastic thermosetting industrial waste in order to produce the composite with properties of thermal insulation: conductivity, thermal diffusivity, specific heat and resistivity. The physical, structural and morphological properties of the raw materials were investigated by thermogravimetry analysis (TG / DSC), X-ray diffraction (DRX), X-ray fluorescence (FXR) and scanning electron microscopy (MEV). Obtaining mechanical properties through the compression strength test. The analysis results indicate characteristics suitable for cement matrix composite production with the addition of thermosetting plastic industrial waste and gypsum waste, with potential application of these materials in composites with properties of thermal insulation. Finally, assessing what proportion showed up with better performance. Considering the analysis and testing carried out.