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Previous issue date: 2011-07-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this study were conducted experimental procedures for determination of variation of
the expandability of rigid polyurethane foam (PUR) from a natural oil polyol (NOP),
specifically the Castor oil plant, Ricinus communis, pure and additions of the vermiculite in
phase dispersed in different percentage within a range from 0% to 20%, mass replacement.
From the information acquired, were defined the parameters for production of bodies of test,
plates obtained through controlled expansion, with the final volume fixed. Initially, the plates
were subjected to thermal performance tests and evaluated the temperature profiles, to later be
extracted samples duly prepared in accordance with the conditions required for each test. Was
proceeded then the measurement of the coefficient of thermal conductivity, volumetric
capacity heat and thermal diffusivity. The findings values were compared with the
results obtained in the tests of thermal performance, contributing to validation of the same.
Ultimately, it was investigated the influence that changes in physical-chemical structure of the
material had exerted on the variation of thermophysical quantities through gas pycnometry,
scanning electron microscopy (SEM) combined with energy dispersive X-ray fluorescence
spectroscopy (EDXRF), infrared spectroscopy using Fourier transform (FTIR),
thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Based on the
results obtained was possible to demonstrate that all load percentage analyzed promoted an
increase in the potential expansion (PE) of the resin. In production of the plates, the
composites with density near at the free expansion presented high contraction during the cure,
being the of higher density adopted as definitive standard. In the thermal performance tests,
the heating and cooling curves of the different composites had presented symmetry and values
very close for lines of the temperature. The results obtained for the thermophysical properties
of composites, showed little difference in respect of pure foam. The percentage of open pores
and irregularities in the morphology of the composites were proportionate to the increment of
vermiculite. In the interaction between the matrix and dispersed phase, there were no
chemical transformations in the region of interface and new compounds were not generated.
The composites of PUR-NOP and vermiculite presented thermal insulating properties near the
foam pure and percentage significantly less plastic in its composition, to the formulation with
10% of load / Neste estudo, foram realizados procedimentos experimentais para determina??o da
varia??o da expansibilidade da espuma r?gida de poliuretano (PUR) de um poliol de ?leo
natural (NOP), especificamente o de mamona, Ricinus communis, puro e acrescido de
vermiculita na fase dispersa, em distintos percentuais, dentro de uma faixa de 0% a 20%, de
substitui??o em massa. A partir das informa??es adquiridas, foram definidos os par?metros
para produ??o dos corpos de prova, placas obtidas atrav?s de expans?o controlada, com
volume final fixo. Inicialmente, as placas foram submetidas a testes de desempenho t?rmico,
sendo avaliados os perfis de temperatura, para posteriormente serem extra?das amostras,
devidamente preparadas conforme as condi??es exigidas para cada ensaio. Procedeu-se ent?o
a medi??o do coeficiente de condutividade t?rmica, capacidade t?rmica volum?trica e difusividade t?rmica.
Os valores encontrados foram comparados com os resultados obtidos
nos testes de desempenho t?rmico, contribuindo para valida??o dos mesmos. Por fim, foi
investigada a influ?ncia que as altera??es na estrutura f?sico-qu?mica do material, exerceram
sobre a varia??o das grandezas termof?sicas, por meio de picnometria a g?s, microscopia
eletr?nica de varredura (MEV) combinada com espectroscopia de fluoresc?ncia de raios-X
por energia dispersiva (EDXRF), espectroscopia de infravermelho com transformada de
Fourier (FTIR), an?lise termogravim?trica (TGA) e an?lise t?rmica diferencial (DTA). Com
base nos resultados obtidos foi poss?vel demonstrar que todos os percentuais de carga
analisados promoveram um aumento do potencial de expans?o (PE) da resina. Na produ??o
das placas, os comp?sitos com densidade pr?xima ? expans?o livre apresentaram grande
contra??o na cura, sendo adotados os de maior densidade como padr?o definitivo. Nos ensaios
de desempenho t?rmico, as curvas de aquecimento e resfriamento dos diferentes comp?sitos
apresentaram simetria e valores muito pr?ximos para as linhas de temperatura. Os resultados
obtidos para as propriedades termof?sicas dos comp?sitos, demonstraram pouca diferen?a em
rela??o aos da espuma pura. O percentual de poros abertos e irregularidades na morfologia
dos comp?sitos foram proporcionais ao incremento da vermiculita. Na intera??o entre matriz
e fase dispersa n?o ocorreram transforma??es qu?micas na regi?o de interface e n?o foram
gerados novos compostos. Os comp?sitos de PUR-NOP e vermiculita apresentaram
propriedades isolantes t?rmicas pr?ximas as da espuma pura e percentual significativamente
menor de pl?stico em sua composi??o, para a formula??o com 10% de carga
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15575 |
| Date | 11 July 2011 |
| Creators | Rahn, Marco Aur?lio dos Santos |
| Contributors | CPF:35846852491, http://lattes.cnpq.br/0490476694313938, Medeiros, Otoniel Marcelino de, CPF:05686890463, http://lattes.cnpq.br/4877133404601046, Santos, Edna Santiago Benta dos, CPF:71313338915, http://lattes.cnpq.br/3370436670254103, Souza, Roberto Silva de, CPF:44466927472, http://lattes.cnpq.br/4012782800846844, Rocha, Alan Carlos Bueno da, CPF:38060680978, http://lattes.cnpq.br/0793006550677962, Marinho, George dos Santos |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Mec?nica, UFRN, BR, Tecnologia de Materiais; Projetos Mec?nicos; Termoci?ncias |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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