As fibras naturais estao ganhando espaco no mercado como materia-prima por apresentarem caracteristicas desejaveis para aplicacoes industriais, por ser um material renovavel, biodegradavel e de baixo custo. Neste sentido, a exploracao da celulose vem crescendo, inclusive no estudo de compositos polimericos reforcados com fibras naturais. Este trabalho visa primeiramente a obtencao de hibridos celulose/oxido de niobio hidratado a partir do tratamento e modificacao do bagaco de cana-de-acucar, e posteriormente a geracao de compositos de matriz de polietileno de baixa densidade (PEBD) e carga de celulose modificada. O Nb2O5.nH2O foi gerado pelo metodo da precipitacao convencional, partindo-se de niobio metalico. Os hibridos foram produzidos nas proporcoes de 10, 20, 30 e 40% de oxido e caracterizados utilizando-se as seguintes tecnicas: difracao de raios X (DRX), espectroscopia de absorcao no infravermelho com transformada de Fourier (FTIR), termogravimetria (TG), calorimetria exploratoria diferencial (DSC) e microscopia eletronica de varredura (MEV). Os resultados indicam que houve boa interacao entre a fibra de celulose e o oxido de niobio hidratado em todas as proporcoes estudadas. Pelas curvas DSC em atmosfera oxidativa pode-se observar que o Nb2O5.nH2O agiu como um agente retardante a chamas. A proporcao do hibrido definida para a geracao dos compositos foi 90Cel/10Nb2O5.nH2O. Inicialmente foram fabricados os compositos reforcados apenas com celulose branqueada, (x)PEBD/(100-x)Cel, com x = 5, 10, 15 e 20, e realizado o estudo de suas propriedades fisico-quimicas: FTIR, TG, DSC, MEV; e dos testes mecanicos. A partir dos dados obtidos definiu-se a proporcao 5% de reforco para a geracao dos compositos reforcados com o hibrido, 95PEBD:5Cel/Nb2O5.nH2O, e tambem com a adicao do agente compatibilizante: polietileno modificado com anidrido maleico (PE-g-AM), 95PEBD:5Cel/Nb2O5.nH2O+5PE-g-AM. A insercao das fibras de celulose a matriz polimerica gera um material mais resistente e rigido e com menor deformacao, assim como a presenca do Nb2O5.nH2O. O PE-g-AM aumenta o valor do modulo elastico. A utilizacao de uma menor granulometria de carga promove uma maior dispersao e uniformidade da celulose da matriz. A dispersao das fibras na matriz dificulta o processo migracao das cadeias moleculares do PEBD, diminuindo o grau de cristalinidade. Os valores de ?Hf mostram que a adicao do inorganico enfraquece a interacao interfacial da matriz com o reforco, diminuindo a ?Hf e a XC. A presenca do Nb2O5.nH2O nos compositos gera um aumento da Tf. / Natural fibers are in prominent position in the researches as raw material for presenting characteristics desirable for industrial applications; it is a renewable material, biodegradable and low cost. Thus, the exploration of cellulose has been growing, including the study of polymer composites reinforced with natural fibers. This study primarily aims to obtain hybrids cellulose/hydrous niobium oxide from the treatment and modification of sugarcane bagasse, and subsequently the generation of composites with matrix of low density polyethylene (LDPE) and modified cellulose as reinforcement. The Nb2O5.nH2O was generated by the conventional precipitation method, starting from niobium metal. The hybrids were produced in proportions of 10, 20, 30 and 40% of oxide and characterized using the following techniques: x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results indicated good interaction between the cellulose fiber and niobium oxide hydrate in all ratios studied. For the DSC curves in oxidative atmosphere can be observed that the Nb2O5.nH2O acted as an agent flame retardant. The proportion of the hybrid set for the generation of composites was 90Cel/10Nb2O5.nH2O. Initially were manufactured composites reinforced only with bleached cellulose, (x)LDPE/(100-x)Cel, with x = 5, 10, 15 and 20, and was conducted the study the physicochemical properties: FTIR, TGA, DSC, SEM; and mechanical properties by the tensile tests. According to this results was defined the percentage of 5% for the generation of composites reinforced with hybrid 95PEBD:5Cel/Nb2O5.nH2O, and also with the addition of compatibilizing, polyethylene modified with maleic anhydride (PE-g-MA), 95PEBD:5Cel/Nb2O5.nH2O+5PE-g-MA. The inclusion of cellulose fibers to the polymer matrix creates a material more resistant and rigid and with a smaller deformation, as well as the presence of Nb2O5.nH2O. The PE-g-MA increases the value of elastic modulus. The use of a smaller particle size of load promotes greater uniformity and dispersion of the cellulose in the matrix. The dispersion of fibers in the matrix hinders the migration process of the molecular chains of LDPE, reducing the degree of crystallinity. ZHf values show that the addition of inorganic weakens the interaction at the matrix with the reinforcement, decreasing ZHf and XC. The presence of the Nb2O5.nH2O in composites generates an increase in Tf.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-08-18T17:45:44Z No. of bitstreams: 1 2010 - Isabel Matos de Fraga.pdf: 5201934 bytes, checksum: 6bbaeba09901aea4cbaa9f69dbb0402e (MD5) / Made available in DSpace on 2017-08-18T17:45:44Z (GMT). No. of bitstreams: 1 2010 - Isabel Matos de Fraga.pdf: 5201934 bytes, checksum: 6bbaeba09901aea4cbaa9f69dbb0402e (MD5) Previous issue date: 2010-12-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / The researches on recycling of industrial wastes has been stepped up around the world to enhance the quality of the recycled product and provide greater efficiency of the productive system. The recycling of plastic materials has also grown in recent years, with Brazil improving its market position. In this way, this work aimed the development of composite materials using as a matrix, the low density polyethylene recycled (PEBDrec), chemical treated with oxidizing agents and, as fillers, E-cat and waste of scale. The PEBDrec was treated with oxidizing agent in order to cause modifications over its chemical structure and to improve compatibility with the residues of scale and E-cat. Were produced composites of PEBDrec treated with hydrogen peroxide (H2O2) and scale; PEBDrec treated with hydrogen peroxide and E-cat; PEBDrec treated with potassium permanganate (KmnO4) and scale and PEBDrec treated with potassium permanganate and E-cat. Were also obtained composites of PEBDrec untreated and mixed with scale or E-cat, to evaluate the action of the oxidizing agent in the compatibility between fillers that were used and the polymer matrix. The results obtained by the analysis of FTIR, XDR, TGA, SEM and mechanicals tests presented that the composites of PEBDrec treated with oxidizing agents showed a good interaction between the dispersed phase and the polymer matrix in comparison to composites PEBDrec without chemical treatment, and this compatibility was better for the lowest proportions. But this good interaction resulted in a decrease of thermal stability of composites in relation to the polymer matrix. It was also observed that the oxidizing agent KMnO4 was more effective in increasing the compatibility between the polymer and the E-cat, while the oxidizing agent H2O2 acted more strongly on increasing the compatibility between the polymer and scale. The composites of PEBDrec untreated, compared to the composites of PEBDrec treated with H2O2 and treated with KMnO4 , had a lower water absorption, indicating that chemical treatment was effective to modify the structure of the polymer, inducing the surface to a greater polarity, giving the chemical treated composites of PEBDrec a higher affinity to water. However a material more mechanical resistant was obtained just with the untreated polymer. The incorporation of the charges in the polymer matrix did not change the density of the material composites, indicating that despite of these materials be crystalline, they present low density, being possible to be used in civil construction. / As pesquisas sobre a reciclagem de res?duos industriais v?m sendo intensificadas em todo o mundo a fim de aumentar a qualidade do produto reciclado e propiciar maior efici?ncia do sistema produtivo. O reaproveitamento de materiais pl?sticos tamb?m tem crescido nos ?ltimos anos, com o Brasil melhorando seu posicionamento no mercado. Nesse sentido, essa disserta??o objetivou o desenvolvimento de materiais comp?sitos utilizando como matriz, o polietileno de baixa densidade reciclado (PEBDrec), tratado quimicamente com agentes oxidantes e como cargas, res?duos de Carepa e E-cat. O PEBDrec foi submetido a tratamento com agentes oxidantes com o objetivo de causar modifica??es na sua estrutura qu?mica e, propiciar uma melhoria na compatibilidade com os res?duos de carepa e E-cat. Foram produzidos comp?sitos de PEBDrec tratado com per?xido de hidrog?nio (H2O2) e carepa; PEBDrec tratado com per?xido de hidrog?nio e E-cat; PEBDrec tratado com permanganato de pot?ssio (KMnO4) e carepa e PEBDrec tratado com permanganato de pot?ssio e E-cat. Tamb?m foram obtidos comp?sitos de PEBDrec n?o tratado misturado a carepa ou E-cat, para avaliar a a??o do agente oxidante na compatibilidade entre a matriz polim?rica e as cargas utilizadas. Os resultados obtidos pelas an?lises de FTIR, DRX, TGA, MEV e ensaios mec?nicos mostraram que os comp?sitos de PEBDrec tratado com os agentes oxidantes apresentaram uma boa intera??o entre a fase dispersa e a matriz polim?rica em compara??o aos comp?sitos de PEBDrec sem o tratamento qu?mico, e essa compatibilidade foi melhor para as menores propor??es. Por?m, essa boa intera??o acarretou em uma diminui??o da estabilidade t?rmica dos comp?sitos, em rela??o a matriz polim?rica. Tamb?m foi poss?vel observar que o agente oxidante KMnO4 foi mais eficaz no aumento da compatibilidade entre o pol?mero e o E-cat, enquanto que o agente oxidante H2O2 atuou mais fortemente no aumento da compatibilidade entre o pol?mero e a carepa. Os comp?sitos de PEBDrec n?o tratado, em compara??o aos comp?sitos de PEBDrec tratados com H2O2 e tratados com KMnO4, apresentaram uma menor absor??o de ?gua, indicando que o tratamento qu?mico foi eficaz para modificar a estrutura do pol?mero deixando sua superf?cie com maior polaridade e conferindo aos comp?sitos de PEBDrec tratado quimicamente uma maior afinidade pela ?gua. Por?m um material mais resistente mecanicamente s? foi obtido com o pol?mero n?o tratado. A incorpora??o das cargas na matriz polim?rica praticamente n?o alterou a densidade desses materiais comp?sitos, indicando que apesar de eles serem materiais cristalinos, eles apresentam baixa densidade, sendo poss?vel suas aplica??es no ramo da constru??o civil.

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

Orientador: Jose de Assis Fonseca Faria / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T11:53:49Z (GMT). No. of bitstreams: 1 Cardoso_ClaudioFernandes_M.pdf: 1146025 bytes, checksum: 703b38e7eec6c1ffc7f2de65b30ab581 (MD5) Previous issue date: 2007 / Resumo: O objetivo deste trabalho consistiu no processamento e avaliação de desempenho de um sistema asséptico piloto para filme de polietileno de baixa densidade (PEBD). Através da metodologia de planejamento experimental fatorial foram feitas variações de tempo de contato, temperatura do banho e concentração da solução esterilizante, bem como a variação do tempo de exposição à radiação ultravioleta (UVC). Estas variações tiveram por finalidade promover de 4 a 6 reduções decimais na população inicial de esporos de Bacillus subtilis var. globigii ATCC9372, em um curto espaço de tempo, gerando o menor residual do esterilizante em água envasada. Foram inoculados uniformemente 100µL do microrganismo teste em uma superfície de 16cm2. Testou-se como agente de esterilização química, o peróxido de hidrogênio (H2O2) e, como agente físico, a radiação UVC, sendo o primeiro aplicado na forma de banho de imersão e o segundo, por uma exposição a 2,5cm de distância do filme de PEBD logo após o banho de imersão. O sistema utilizado constituiu em uma envasadora automática e um protótipo com um tanque em aço inoxidável, desenvolvido especialmente para este tipo de teste. O H2O2 e a radiação UVC apresentaram ação esporicida significativa. O H2O2 demonstrou ação esporicida entre as concentrações de 18 e 35%, em um intervalo de temperatura de 46 a 70ºC, promovendo de 3 a 7 reduções decimais de Bacillus subtilis. A concentração de 20% de H2O2 não conferiu sabor estranho à água mineral envasada em embalagens de PEBD sanificadas, não diferindo, significativamente (p<0,05), do padrão. O residual de H2O2 das superfícies-teste sanificadas com soluções contendo de 18 a 35% de H2O2 foi superior a 0,5mg/L, nível máximo permitido pela FDA presente em água envasada sob as condições de produção. Os dados obtidos forneceram dois modelos matemáticos quadráticos, representativos da ação do H2O2 e radiação UVC, em função do tempo e da temperatura, sobre esporos de B. subtilis. Tais modelos, com R2 de 0,9349 para os tratamentos sem radiação UVC, e R2 de 0,9763 para os tratamentos com radiação UVC, limitaram-se a uma concentração de 35% de H2O2 e tempo máximo de exposição à radiação UVC de 8s. Superfícies-teste sanificadas com soluções de 28% de H2O2 a 60ºC, por 8s sem exposição à radiação UVC apresentaram 4 ciclos de redução decimal. Para as mesmas condições, porém com exposição à radiação UVC por 8s, este valor elevou-se para 7, demonstrando a existência do sinergismo entre a associação destes dois agentes. O sistema de esterilização testado apresentou desempenho satisfatório, podendo ser perfeitamente utilizado por indústrias de pequeno e médio porte na esterilização de filmes plásticos, sendo capaz de promover até 7 reduções decimais na população de esporos bacterianos / Abstract: The aim of this research consisted in the processing and performance evaluation of an aseptic pilot system for Low Density Polyethylene film (LDPE). Through the screening design methodology, variations of contact time, bath temperature, sanificant concentration and exposition time variation of ultraviolet radiation (UVC) was made. Such variations had as purpose to promote from 4 to 6 decimal reductions in the Bacillus subtilis var. globigii ATCC9372 spores, when applied to the LDPE film surface, in a short time, generating the minor residual of the sanificant in the plastic surface. Was evaluated as chemical agent, the hydrogen peroxide (H2O2) and as physical agent, UVC radiation, being the first one applied as immersion bath and the second one as an exposition after the immersion bath, with 2,5cm of distance of the PEBD film. The system used was constituted in an automatic filling machine and an equipment with a stainless steel tank, especially developed for this type of test. H2O2 showed sporicidal action in from 18 to 35%, in temperatures of 46 to 70ºC, causing from 3 to 7 decimal reductions. The H2O2 20% did not confer off-taste in mineral water used as filling product, as well no significant difference from the standard was observed (p<0,05). The hydrogen peroxide residual surface-test after sanitation with 18 to 35% H2O2 was higher than 0,5mg/L. However, the use of hot air knives or roller pressers after the immersion bath will be able to diminish this residual. The quadratic model, with R2 of 0,9349 for the treatments without UVC radiation and R2 of 0,9763 for the treatments with UVC radiation are restricted to 35% H2O2 and UVC maximum exposition time of 8s. Surface-test treated with 28% H2O2 / 60ºC / 8s without UVC radiation exposition had presented 4 decimal reduction. In the same conditions, however with UVC radiation exposition (8s), this value was raised for 7, demonstrating the existence of synergism between these two agents. The sanification system tested showed satisfactory performance, effective to be used in small and medium industries, being capable to promote up to 7 decimal reductions in spores population / Mestrado / Mestre em Tecnologia de Alimentos

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-06T11:42:39Z No. of bitstreams: 1 2016 - C?ssia Thais Silva Santos.pdf: 4767415 bytes, checksum: 7078f4a6b3c6455dd65b9fa432b3a6ff (MD5) / Made available in DSpace on 2017-06-06T11:42:39Z (GMT). No. of bitstreams: 1 2016 - C?ssia Thais Silva Santos.pdf: 4767415 bytes, checksum: 7078f4a6b3c6455dd65b9fa432b3a6ff (MD5) Previous issue date: 2016-07-20 / It is crescent the research by new materials and methods for creating and same market insertion. Currently, among the various types of waste, electronic waste is considered obsolete in a very short time and require proper disposal. In Brazil, the last year, the reuse of plastic materials has increased. This study aimed to research the importance of mobile phones waste recycling, which have short pace of useful life used as reinforcements, no development of new materials containing recycled thermoplastic polymer (Low Density Polyethylene LDPE) and from the analyzes mechanical and dangerousness of these new materials, so justify the replacement of the importance of some materials with longer life time and easy recyclability, that form provides a reduction of environmental impacts caused by the generated waste were developed six blends of (Low Density Polyethylene recycled and PCABS carcasses - LDPErec/PC-ABS), with composition and grain size variation of cell granulometry housing and also an analysis of pure materials. The results obtained for analysis of diffraction X-ray, density, water absorption, hardness, scanning electronic microscopy and mechanical testing showed one low interaction between polymers, beyond the performance of the amorphous polymer morphology and hence the crystallinity mix, directly affected at the thermal and mechanical properties. As for the hazard analysis of the materials developed, they were not found excess levels of metal toxicants, the limits established by ABNT NBR 10004 / ? crescente a pesquisa por novos materiais e metodologias para a cria??o e inser??o dos mesmos no mercado. Atualmente, dentre os diversos tipos de res?duos, os res?duos eletroeletr?nicos tem aumentado exponencialmente, pois estes tem sido considerados obsoletos em um intervalo de tempo muito curto e necessitam de descarte adequado. No Brasil, nos ?ltimos anos, o reaproveitamento de materiais pl?sticos tamb?m tem aumentado. Neste contexto, este trabalho teve como objetivo pesquisar a import?ncia da reciclagem de res?duos de telefones celulares (carca?as), que possuem curto tempo de vida ?til, utilizados como refor?os, no desenvolvimento de novos materiais, contendo pol?mero termopl?stico reciclado (polietileno de baixa densidade ? PEBD) e, a partir das an?lises mec?nicas e da periculosidade destes novos materiais, justificar a import?ncia da substitui??o de alguns materiais por outros com maior tempo de vida ?til e de f?cil reciclabilidade, de forma que proporcione a redu??o dos impactos ambientais provocados com os res?duos gerados. Para tal, foram desenvolvidas 6 blendas de (Polietileno de baixa densidade reciclado e carca?as de PC-ABS - PEBDrec/PC-ABS), com varia??o da composi??o e granulometria das carca?as de aparelhos celular, e tamb?m a an?lise dos mat?rias puros. Os resultados obtidos pelas an?lises de difra??o de raios-X, densidade, absor??o de ?gua, dureza, microscopia eletr?nica de varredura e ensaios mec?nicos mostraram que a baixa intera??o entre os pol?meros, al?m da atua??o do pol?mero amorfo na morfologia e, consequentemente, na cristalinidade da mistura, afetou diretamente nas propriedades t?rmicas e mec?nicas. Quanto ? an?lise de periculosidade dos materiais desenvolvidos, n?o foram encontrados n?veis excedentes de metais t?xicos, conforme limites estabelecidos pela NBR ABNT 10004.

No description available.

In this research study, a strategy was used for assigning stiffness values to various layers of the pavement system so that there are negligible tensile stresses in the subgrade and base layers. The stiffnesses of the aggregate base layers were assigned double the values of the corresponding subgrade materials. The layer thicknesses were designed to achieve surface deflection values within the acceptable limit. An innovative design procedure was developed for designing pavement sections covering various layer thicknesses, material and environmental variables. The designed sections were compared with the American Association of State Highway and Transportation Officials (AASHTO) procedure and the differences were critiqued. Porous asphalt layer was used as the surface course for all pavement sections. The calculations validated the general principle of pavement design, as the subgrade stiffness decreased the base thickness increased for the same surface course thickness and traffic. Structural design of 63 pavements sections was accomplished representing various temperature and materials including additives. Low Density Polyethylene, performance graded asphalt, different soils, aggregates, lime and cement were the component materials utilized in this research study. An explanation on the mechanics of the mixtures is given in the results and discussion section. / Civil Engineering

The potential use of Resadiye/Tokat bentonite as a reinforcement in polypropylene (PP) and linear low density polyethylene (LLDPE) polymer matrix nanocomposites filler was investigated. At first, organoclays (OC) were prepared by cation exchange reaction (CER) between the raw bentonite (RB) and three quaternary ammonium salts with long alkyl tails (QA): hexadecyl trimethyl ammonium bromide [HMA] [Br], tetrabutyl ammonium tetrafluoroborate [TBA] [BF4], tetrakisdecyl ammonium bromide [TKA] [Br] and one quaternary phosphonium (QP) salt: tetrabutyl phosphonium tetrafluroborate [TBP] [BF4]. Characterization of resulting materials by XRD, TGA, FTIR and chemical analysis confirmed the formation of organoclays. Ternary composites of PP/organoclay/ maleic anhydride grafted polypropylene (MAPP) were prepared with two different grades of PPs in a co-rotating twin screw extruder. Composites prepared with these organoclays and PPs showed microcomposite formation. In the second part of the study, raw bentonite was purified by sedimentation, and characterization of purified bentonite (PB) by XRD, cation exchange capacity (CEC) measurement and chemical analysis (ICP) confirmed the success of purification method. PB was then modified with two QA`s: dimethyl dioctadecylammonium chloride [DMDA] [Cl], tetrakis decylammonium bromide [STKA] [Br] and one QP: tributyl hexadecyl phosphonium bromide [TBHP] [Br]. Organoclays from PB were used with the PP with lower viscosity, and ternary nanocomposites (PP/Organoclay2/MAPP5) were prepared in the extruder followed by batch mixing in an intensive batch mixer. Use of DMDA and TBHP OCs resulted in nanocomposite formation, while STKA resulted in microcomposite formation as observed by XRD and TEM. Young`s modulus and yield stress of the samples were enhanced through nanocomposite formation. In the last part of the study, ternary composites of LLDPE/Organoclay/ compatibilizer, a random terpolymer of ethylene, butyl acrylate and maleic anhydride (E-BA-MAH, Lotader&reg / 3210), were prepared by melt compounding in the batch mixer at two different clay concentrations (2 and 5 wt %) and fixed compatibilizer/organoclay ratio (&alpha / =2.5). A commercial organoclay, I34, was also used in LLDPE based nanocomposites to make a comparison. XRD and TEM analyses of the compounds prepared by DMDA and TBHP showed mixed nanocomposite morphologies consisting of partially intercalated and exfoliated layers. Young`s modulus and tensile strength of nanocomposites prepared with DMDA and TBHP showed generally higher values compared to those of neat LLDPE, while results were the highest in the composites prepared with commercial organoclay I34. Parallel disk rheometry was used as a supplementary technique to XRD, TEM and mechanical characterizations, and it was shown to be a sensitive tool in assessing the degree of dispersion of clay layers in the polymer matrix.

Submitted by GIOVANNI BARRERA TORRES null (gbarrerat01@gmail.com) on 2017-08-04T04:24:40Z No. of bitstreams: 1 TESE VERSÃO FINAL Giovanni Barrera Torres.pdf: 6197644 bytes, checksum: d321626a0e947c39627bbfe43b7aaf87 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-08-04T19:37:47Z (GMT) No. of bitstreams: 1 torres_gb_dr_prud.pdf: 6197644 bytes, checksum: d321626a0e947c39627bbfe43b7aaf87 (MD5) / Made available in DSpace on 2017-08-04T19:37:47Z (GMT). No. of bitstreams: 1 torres_gb_dr_prud.pdf: 6197644 bytes, checksum: d321626a0e947c39627bbfe43b7aaf87 (MD5) Previous issue date: 2017-06-21 / Asociación Universitaria Iberoamericana de Postgrado (AIUP) / A presente pesquisa foi projetada para promover o desenvolvimento de compósitos poliméricos a partir da mistura de polietileno de baixa densidade (PEBD) com borracha natural (BN) reforçada com a cinza, resíduo da queima do bagaço, a cinza da cana de açúcar (CBC). Uma das propostas desta pesquisa foi direcionar uma aplicação ao resíduo, que é um material abundante e descartado, gerado no processo usual das usinas. A borracha natural empregada foi obtida a partir do látex de seringueira de Hevea Brasiliensis, Clone RRIM 600 muito cultivado no Brasil. A fim de se estudar separadamente a interação entre a CBC junto a BN e os agentes de vulcanização. Foi estudada numa primeira etapa: a mistura de borracha natural com a cinza de bagaço da cana até desenvolver uma mistura chamada de master, com boas propriedades de tensão e deformação. Foram produzidos compósitos elastoméricos aplicando agente silano como sistema de acoplamento. Numa segunda etapa o master compatibilizado foi misturado ao PEBD sem o uso de agentes de vulcanização; a finalidade destes compósitos foi de estudar a interação dos constituintes visando obter um compósito com o mínimo de agentes químicos e funcional para a indústria. Numa última etapa foram desenvolvidas blendas e compósitos termoplásticos vulcanizáveis (TPV); nesta etapa foram aplicados os agentes de vulcanização empregados na primeira etapa da pesquisa. As amostras foram estudadas por meio das técnicas de análises estruturais (FT-IR); físico-mecânicas (tensão e deformação; dinâmicas e mecânicas, DMA); térmicas (DSC e TG); dureza (Shore A). Foram obtidos resultados sobressalientes em comparação com as amostras sem agentes de vulcanização nas amostras com 50 % de master e 50 % de PEBD na resposta de elongação e tensão; a dureza acima do Shore A 85 obtida, foi produto da porcentagem da fase de PEBD presente nas amostras; nas análises térmicas foi possível observar degradação acima dos 160 oC resultando uma boa característica para aplicações industriais. Com os resultados obtidos tornou-se possível direcionar tanto a CBC como os compósitos para aplicações tecnológicas a fim de serem utilizados na fabricação de cabos de ferramentas, amortecedores, produtos para o lar, entre outros. / The present research was aimed to promote the development of polymeric composites from the mixture of low density polyethylene (LDPE) with natural rubber reinforced with ash, residue of the burning of sugarcane bagasse (SCB). One of the proposals of this research was to direct an application to the residue, which is an abundant and discarded material, generated in the usual process of the plants. The natural rubber used was obtained from rubber latex clone of Hevea Brasiliensis, Clone RRIM 600 widely cultivated in Brazil. In order to study separately the interaction between SCB with NR and vulcanization agents. It was developed in the first stage: the mixing of natural rubber with the sugarcane bagasse ash to develop a mixture called master, with good tensile and deformation properties. Elastomeric composites were produced by applying silane as a coupling agent. In a second stage the compatibilized master was mixed to the LDPE without the use of vulcanization agents; the purpose of these composites was to study the interaction of the constituents in order to obtain a composite with the minimum of chemical and functional agents for the industry. In the latter stage vulcanizable thermoplastic blends and thermoplastic composites were developed; In this stage the vulcanization agents used in the first stage of the research were applied. The samples were studied using structural analysis techniques (FT-IR); Physical-mechanical (tension and deformation, dynamic and mechanical, DMA); (DSC and TG); Hardness (Shore A). Sparing results were obtained in comparison with the samples without vulcanization agents in samples with 50 % of master and 50 % of LDPE in the strain and stress response; the hardness above Shore A 85, obtained was the product of the percentage of the LDPE phase present in the samples; In the thermal analyzes it was possible to observe degradation above 160 oC resulting in a good characteristic for industrial applications. With the results obtained, it became possible to target both SCB and composites for technological applications in order to be used in the manufacture of tool cables, shock absorbers, household products, among others. / AIUP: A0 185864

In current enterprises, simulations are being utilized to lessen the cost of product advancement.  Along this line, there is an awesome enthusiasm for enhancing precision and accuracy of simulations. For an accurate and reliable simulation, it is essential to use an accurate material model and provide it with accurate material information. In exhibit industries, orthotropic materials are being simulated utilizing isotropic material model, as orthotropic material model requires more material data which is not promptly accessible. This proposal intends to test and identify orthotropic materials and simulate them using orthotropic material model in ABAQUS. Materials utilized as a part of this proposal are Aluminium, LDPE, PET. Required material data was gotten by performing Uni-directional tensile tests, DIC, and an algorithm we developed in light of Inverses method. To get highly accurate material data from DIC, a few kinds of patterns were examined, and a superior pattern was resolved for camera configuration being utilized.