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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Utiliza??o de res?duo lignocelul?sico na obten??o de chapa de madeira aglomerada homog?nea e comp?sito refor?ado com fibra de vidro-E

Silva, Luiz Claudio Ferreira da 10 July 2008 (has links)
Made available in DSpace on 2014-12-17T14:06:58Z (GMT). No. of bitstreams: 1 LuizCFS.pdf: 3453741 bytes, checksum: a917d4da21cccce053bc103345ba7ee6 (MD5) Previous issue date: 2008-07-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This research is about the use of the coconut?s endocarp (nucifera linn) and the waste of derivatives of wood and furniture as raw material to technological use. In that sense, the lignocellulosic waste is used for manufacture of homogeneous wood sheet agglomerate (LHWS) and lignocellulosic load which take part of a polymeric composite with fiber glass E (GFRP-WC). In the manufacturing of the homogeneous wood sheet agglomerate (LHWS), it was used mamona?s resin as waste s agglutinating element. The plates were taken up in a hydraulic press engine, heated, with temperature control, where they were manufactured for different percentage of waste wood and coconuts nuc?fera linn. Physical tests were conducted to determine the absorption of water, density, damp grade (in two hours and twenty-four hours), swelling thickness (in two hours and twenty-four hours), and mechanical tests to evaluate the parallel tensile strength (internal stick) and bending and the static (steady) flexural. The physical test?s results indicate that the LHWS can be classified as bonded wood plate of high-density and with highly water resistant. In the mechanical tests it was possible to establish that LHWS presents different characteristics when submitted to uniaxial tensile and to the static (steady) flexural, since brittle and elasticity module had a variation according to the amount of dry endocarp used to manufacture each trace of LHWS. The GFRP-WC was industrially manufactured by a hand-lay-up process where the fiber glass E was used as reinforcement the lignocellul?sic?s waste as load. The matrix was made with ortofitalic unsaturated polyester resin. Physical and mechanical tests were performed in presence of saturated humidity and dry. The results indicated good performance of the GFRP-WC, as traction as in flexion in three points. The presence of water influenced the modules obtained in the flexural and tensile but there were no significant alteration in the properties analyzed. As for the fracture, the analysis showed that the effects are more harmful in the presence of damp, under the action of loading tested, but despite this, the fracture was well defined starting in the external parts and spreading to the internal regions when one when it reaches the hybrid load / Na presente pesquisam-se a utiliza??o do endocarpo do cocos nuc?fera linn e o res?duo de derivados de madeira e de m?veis como mat?ria-prima para uso tecnol?gico. Nesse sentido, usam-se esses res?duos lignocelul?sico na fabrica??o de chapa de madeira aglomerada homog?nea (CHMC) e, como carga, em comp?sito polim?rico refor?ado com fibra de vidro E (PHFV-MC). Na fabrica??o da chapa de madeira aglomerada homog?nea (CHMC) usou-se a resina ? base de mamona como elemento aglutinante dos res?duos. As chapas foram conformadas em uma prensa hidr?ulica aquecida com controle de temperatura, onde as mesmas foram fabricadas para diferentes percentuais dos res?duos de madeira e do cocos nuc?fera linn. Foram realizados ensaios f?sicos para a determina??o de absor??o de ?gua, densidade, do teor de umidade (em duas horas e vinte e quatro horas), inchamento de espessura (em duas horas e vinte e quatro horas), e ensaios mec?nicos para a determina??o da resist?ncia ? tra??o paralela (ades?o interna) e o ensaio de flex?o est?tica. Os resultados obtidos nos ensaios f?sicos indicam que a CHMC pode ser classificada como chapa de madeira aglomerada de alta densidade e que suporta bem a presen?a de ?gua. Nos ensaios mec?nicos foi poss?vel constatar que a CHMC apresenta caracter?sticas distintas quando submetida ? for?a de tra??o uniaxial e ? flex?o est?tica, uma vez que os m?dulos de ruptura e de elasticidade variaram em fun??o da quantidade do endocarpo seco usado para fabricar cada tra?o da CHMC. A PHFV-MC foi fabricada industrialmente por meio do processo hand-lay-up onde a fibra de vidro-E foi usada como refor?o e os res?duos lignocelul?sicos, como carga. A matriz foi ? base de resina poli?ster ortofit?lica insaturada. Foram realizados ensaios f?sicos e mec?nicos em presen?a de umidade saturada e a seco. Os resultados indicaram um bom desempenho da PHFV-MC, tanto na tra??o quanto na flex?o em tr?s pontos. A presen?a de ?gua influenciou os m?dulos obtidos na flex?o e na tra??o, mas n?o alterou significativamente as propriedades analisadas. Quanto ? fratura, a an?lise mostrou que os efeitos s?o mais danosos em presen?a da umidade, sob a a??o dos carregamentos analisados, mas, apesar disto, a fratura se mostrou bastante caracterizada, iniciando nas regi?es externas e se propagando para as regi?es internas quando atinge a carga h?brida

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