Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim
Autor(a) principal: | |
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Data de Publicação: | 2018 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFU |
Texto Completo: | https://repositorio.ufu.br/handle/123456789/26859 http://dx.doi.org/10.14393/ufu.di.2018.1235 |
Resumo: | In this work the reinforcement of Portland cement matrices with cellulose kraft pulps was studied. It is known that the alkalinity of the cement paste deteriorates the fiber. In this sense, we tried to produce a less aggressive matrix to the fibers by adding natural latex and replacing part of the Portland cement for metakaolin. Flexural strength tests and water absorption were made on composites at 28 days of age. After the flexural tests, the samples were submitted to X-ray diffraction and scanning electron microscopy. The influence of the analyzed parameters (percentage of cellulose, percentage of latex and percentage of metakaolin) on the mechanical and physical properties of the composites was evaluated through a experimental design. From this design it was possible to develop a model of equations that optimized the results of toughness, modulus of rupture, modulus of elasticity and water absorption. The composite with 1.252% cellulose, 1.126% latex and 37.06% metakaolin presented the best modulus of elasticity, equal to 21.89 GPa at 28 days of age. The best flexural strength and toughness was presented by the composite with 8.5% cellulose, 0.21% latex and 34% metakaolin, with a modulus of rupture of 14.42 MPa and a toughness of 1.68 kJ/m² at 28 days of age. Analyzing the results obtained by attenuated total reflection and by contact angle, it was possible to prove that the latex was possibly adhered to the pulp, hydrophobising it. Therefore, it was concluded that it is possible to use the natural latex emulsion in the cellulosic pulp and metakaolin for the production of cementitious composites. |
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Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulimStudy of Portland cement composites with pulp kraft cellulose modified with natural rubber latex and metakaolinCompósitosCeluloseEmulsão de látex naturalMetacaulimPlanejamentoCompositesCelluloseNatural rubber latexMetakaolinDesign of experiments.Módulo de rupturaTenacidadeMódulo de elasticidadeAbsorção de águaSuperfície de respostaAnálise canônicaModulus of ruptureToughnessYoung's modulusWater absorptionResponse surfaceCanonical analysisCNPQ::ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL::MATERIAIS E COMPONENTES DE CONSTRUCAOIn this work the reinforcement of Portland cement matrices with cellulose kraft pulps was studied. It is known that the alkalinity of the cement paste deteriorates the fiber. In this sense, we tried to produce a less aggressive matrix to the fibers by adding natural latex and replacing part of the Portland cement for metakaolin. Flexural strength tests and water absorption were made on composites at 28 days of age. After the flexural tests, the samples were submitted to X-ray diffraction and scanning electron microscopy. The influence of the analyzed parameters (percentage of cellulose, percentage of latex and percentage of metakaolin) on the mechanical and physical properties of the composites was evaluated through a experimental design. From this design it was possible to develop a model of equations that optimized the results of toughness, modulus of rupture, modulus of elasticity and water absorption. The composite with 1.252% cellulose, 1.126% latex and 37.06% metakaolin presented the best modulus of elasticity, equal to 21.89 GPa at 28 days of age. The best flexural strength and toughness was presented by the composite with 8.5% cellulose, 0.21% latex and 34% metakaolin, with a modulus of rupture of 14.42 MPa and a toughness of 1.68 kJ/m² at 28 days of age. Analyzing the results obtained by attenuated total reflection and by contact angle, it was possible to prove that the latex was possibly adhered to the pulp, hydrophobising it. Therefore, it was concluded that it is possible to use the natural latex emulsion in the cellulosic pulp and metakaolin for the production of cementitious composites.FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisDissertação (Mestrado)Neste trabalho estudou-se o reforço de matrizes de cimento Portland com polpas kraft de celulose. Sabe-se que a alcalinidade da pasta de cimento deteriora a fibra. Nesse sentido, buscou-se produzir uma matriz menos agressiva às fibras por meio da adição de látex natural e substituição de parte do cimento Portland por metacaulim. Ensaios de resistência à flexão e absorção de água foram realizados nos compósitos aos 28 dias de idade. Após os ensaios de flexão, as amostras foram submetidas a análises por difração de raios-X e microscopia eletrônica de varredura. Foi avaliada a influência dos parâmetros analisados (porcentagem de celulose, porcentagem de látex e porcentagem de metacaulim) nas propriedades mecânicas e físicas dos compósitos por meio de um planejamento experimental composto. A partir deste planejamento foi possível desenvolver equações que otimizaram as formulações para obtenção dos melhores resultados de tenacidade, módulo de ruptura, módulo de elasticidade e absorção de água. Novos compósitos com formulações otimizadas foram moldados. A melhor resistência à flexão e tenacidade foi apresentada pelo compósito 8, com 8,5% de celulose, 0,21% de látex e 34% de metacaulim, com módulo de ruptura de 14,42 MPa e tenacidade de 1,68 kJ/m aos 28 dias de idade. Pela análise dos resultados obtidos por infravermelho por transformada de Fourier modo de reflexão total atenuada e por ângulo de contato foi possível comprovar que possivelmente o látex ficou aderido à polpa, hidrofobizando-a. Logo, concluiu-se que é viável a utilização da emulsão de látex natural e metacaulim para produção de compósitos cimentícios com polpa de celulose.Universidade Federal de UberlândiaBrasilPrograma de Pós-graduação em Engenharia CivilMotta, Leila Aparecida de Castrohttp://lattes.cnpq.br/3604233375792763Pasquini, Danielhttp://lattes.cnpq.br/6879704705300161Oliveira, Andrielli Moraishttp://lattes.cnpq.br/9590390602101344Santos, Lara Cristina Péres2019-08-28T19:21:01Z2019-08-28T19:21:01Z2018-07-31info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfSANTOS, Lara Cristina Péres. Estudo de compósitos de cimento Portland com polpa kraft de celulose modificados com látex natural e metacaulim. 2018. 141f. Dissertação (Mestrado em Engenharia Civil) - Universidade Federal de Uberlândia, Uberlândia, 2019. DOI http://dx.doi.org/10.14393/ufu.di.2018.1235https://repositorio.ufu.br/handle/123456789/26859http://dx.doi.org/10.14393/ufu.di.2018.1235porinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFUinstname:Universidade Federal de Uberlândia (UFU)instacron:UFU2020-11-18T13:07:35Zoai:repositorio.ufu.br:123456789/26859Repositório InstitucionalONGhttp://repositorio.ufu.br/oai/requestdiinf@dirbi.ufu.bropendoar:2020-11-18T13:07:35Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU)false |
dc.title.none.fl_str_mv |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim Study of Portland cement composites with pulp kraft cellulose modified with natural rubber latex and metakaolin |
title |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
spellingShingle |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim Santos, Lara Cristina Péres Compósitos Celulose Emulsão de látex natural Metacaulim Planejamento Composites Cellulose Natural rubber latex Metakaolin Design of experiments. Módulo de ruptura Tenacidade Módulo de elasticidade Absorção de água Superfície de resposta Análise canônica Modulus of rupture Toughness Young's modulus Water absorption Response surface Canonical analysis CNPQ::ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL::MATERIAIS E COMPONENTES DE CONSTRUCAO |
title_short |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
title_full |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
title_fullStr |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
title_full_unstemmed |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
title_sort |
Estudo de compósitos de cimento Portland com polpa kraft de celulos modiicados com látex natural e metacaulim |
author |
Santos, Lara Cristina Péres |
author_facet |
Santos, Lara Cristina Péres |
author_role |
author |
dc.contributor.none.fl_str_mv |
Motta, Leila Aparecida de Castro http://lattes.cnpq.br/3604233375792763 Pasquini, Daniel http://lattes.cnpq.br/6879704705300161 Oliveira, Andrielli Morais http://lattes.cnpq.br/9590390602101344 |
dc.contributor.author.fl_str_mv |
Santos, Lara Cristina Péres |
dc.subject.por.fl_str_mv |
Compósitos Celulose Emulsão de látex natural Metacaulim Planejamento Composites Cellulose Natural rubber latex Metakaolin Design of experiments. Módulo de ruptura Tenacidade Módulo de elasticidade Absorção de água Superfície de resposta Análise canônica Modulus of rupture Toughness Young's modulus Water absorption Response surface Canonical analysis CNPQ::ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL::MATERIAIS E COMPONENTES DE CONSTRUCAO |
topic |
Compósitos Celulose Emulsão de látex natural Metacaulim Planejamento Composites Cellulose Natural rubber latex Metakaolin Design of experiments. Módulo de ruptura Tenacidade Módulo de elasticidade Absorção de água Superfície de resposta Análise canônica Modulus of rupture Toughness Young's modulus Water absorption Response surface Canonical analysis CNPQ::ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL::MATERIAIS E COMPONENTES DE CONSTRUCAO |
description |
In this work the reinforcement of Portland cement matrices with cellulose kraft pulps was studied. It is known that the alkalinity of the cement paste deteriorates the fiber. In this sense, we tried to produce a less aggressive matrix to the fibers by adding natural latex and replacing part of the Portland cement for metakaolin. Flexural strength tests and water absorption were made on composites at 28 days of age. After the flexural tests, the samples were submitted to X-ray diffraction and scanning electron microscopy. The influence of the analyzed parameters (percentage of cellulose, percentage of latex and percentage of metakaolin) on the mechanical and physical properties of the composites was evaluated through a experimental design. From this design it was possible to develop a model of equations that optimized the results of toughness, modulus of rupture, modulus of elasticity and water absorption. The composite with 1.252% cellulose, 1.126% latex and 37.06% metakaolin presented the best modulus of elasticity, equal to 21.89 GPa at 28 days of age. The best flexural strength and toughness was presented by the composite with 8.5% cellulose, 0.21% latex and 34% metakaolin, with a modulus of rupture of 14.42 MPa and a toughness of 1.68 kJ/m² at 28 days of age. Analyzing the results obtained by attenuated total reflection and by contact angle, it was possible to prove that the latex was possibly adhered to the pulp, hydrophobising it. Therefore, it was concluded that it is possible to use the natural latex emulsion in the cellulosic pulp and metakaolin for the production of cementitious composites. |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018-07-31 2019-08-28T19:21:01Z 2019-08-28T19:21:01Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
SANTOS, Lara Cristina Péres. Estudo de compósitos de cimento Portland com polpa kraft de celulose modificados com látex natural e metacaulim. 2018. 141f. Dissertação (Mestrado em Engenharia Civil) - Universidade Federal de Uberlândia, Uberlândia, 2019. DOI http://dx.doi.org/10.14393/ufu.di.2018.1235 https://repositorio.ufu.br/handle/123456789/26859 http://dx.doi.org/10.14393/ufu.di.2018.1235 |
identifier_str_mv |
SANTOS, Lara Cristina Péres. Estudo de compósitos de cimento Portland com polpa kraft de celulose modificados com látex natural e metacaulim. 2018. 141f. Dissertação (Mestrado em Engenharia Civil) - Universidade Federal de Uberlândia, Uberlândia, 2019. DOI http://dx.doi.org/10.14393/ufu.di.2018.1235 |
url |
https://repositorio.ufu.br/handle/123456789/26859 http://dx.doi.org/10.14393/ufu.di.2018.1235 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Uberlândia Brasil Programa de Pós-graduação em Engenharia Civil |
publisher.none.fl_str_mv |
Universidade Federal de Uberlândia Brasil Programa de Pós-graduação em Engenharia Civil |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFU instname:Universidade Federal de Uberlândia (UFU) instacron:UFU |
instname_str |
Universidade Federal de Uberlândia (UFU) |
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UFU |
institution |
UFU |
reponame_str |
Repositório Institucional da UFU |
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Repositório Institucional da UFU |
repository.name.fl_str_mv |
Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU) |
repository.mail.fl_str_mv |
diinf@dirbi.ufu.br |
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1805569636823990272 |