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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.
1

Avalia??o da flamabilidade e dos res?duos de queima de tintas acr?licas ? base d'?gua

Henrique, Angelo Abel Machado Pereira 29 September 2017 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-06-04T14:42:13Z No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-11T14:34:47Z (GMT) No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Made available in DSpace on 2018-06-11T14:46:48Z (GMT). No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, the sample-flame propagation indexes were simulated in laboratory, in detriment and in comparison to the generalized burning during the fires in internal environments. The respective chemical and physical properties of the paints, the emanated gases, were compared; evidencing its toxicities, toxicological thresholds and using the tests of horizontal burning and vertical burning. In the experimental part, the paint films were produced for later burning in a quartz chamber with the use of the electric furnace, from which the gases were collected, according to each thermal degradation orientation obtained by the TGA pallet, in order to analyze the toxicities in gas chromatography. In the results the different firing behaviors for each paint can be compared by virtue of its physico-chemical composition, together with its gas release rates in each temperature range. / Neste trabalho produziu-se a partir das tintas acr?licas ? base d??gua, os ?ndices de propaga??o de chama amostral e simulada em laborat?rio, em detrimento e em comparativo ? queima generalizada durante os inc?ndios em ambientes internos. Foram comparadas as respectivas propriedades qu?micas e f?sicas das tintas, dos gases emanados; evidenciando as suas toxicidades, limiares toxicol?gicos e empregando os testes de queima horizontal e queima vertical. Na parte experimental foram produzidos os filmes de tintas, para posterior queima em c?mara de quartzo com o uso do forno el?trico, onde a partir deste, coletou-se os gases, segundo cada orienta??o de degrada??o t?rmica obtida pala TGA, para ent?o serem analisadas as toxicidades em cromatografia gasosa. Nos resultados podem ser comparados os diferentes comportamentos de queima para cada tinta em virtude de sua composi??o f?sico-qu?mica, juntamente com suas taxas de libera??es de gases em cada faixa de temperatura.
2

Estudo da flamabilidade e resist?ncia ? chama de comp?sito de poli?ster insaturado e fibra da folha do abacaxizeiro (PALF)

Ribeiro, Luciene Mendes 11 August 2011 (has links)
Made available in DSpace on 2014-12-17T14:58:10Z (GMT). No. of bitstreams: 1 LucieneMR_DISSERT.pdf: 3721446 bytes, checksum: 16ced8820ae92014f7d8c365770f515c (MD5) Previous issue date: 2011-08-11 / In the present research work, composites were prepared using pine apple leaf fibres (PALF) as reinforcement with unsaturated polyester resin as matrix, incorporating with fire retardant at different compositions. The PALF was obtained from the decortication of pine apple leaves obtained from Ramada 4 from Ielmo Marinho in the State of Rio Grande do Norte. The unsaturated polyester resin and the catalyzer were bought from the local establishment. The fire retardant, aluminium tri-hydroxide - Al(OH)3 was donated by Alcoa Alum?nio S.A and was used in the proportions of 20%, 40% and 60% w/w. Initially the fibres were treated with 2% NaOH for 1 hour, to remove any impurities present on the fibre surface, such as wax, fat, pectin and pectate, in order to have a better adsorption of the fibres with the matrix as well as the flame retardant. The fibre mat was prepared in a mat preparator by immersion, developed in the Textile Engineering Laboratory, at the UFRN. The composites (300x300x3 mm) were prepared by compression molding and the samples (150x25x3 mm) for analysis of the properties were cut randomly using a laser cutter. Some of the cut samples were used to measure the smoke emission and fire resistance using UL94 standard. Mechanical tension-extension and flexural properties were carried in CTG?s RN and the Laborat?rio de Metais e Ensaios Mec?nicos Engenharia de Materiais UFRN , as well as SEM studies were carried out at N?cleo de Estudos em Petr?leo e G?s Natural - UFRN . From the observed results, it was noted that, there was no marked influence of the fire retardant on the mechanical properties. Also in the water absorption test, the quantity of water absorbed was less in the sample with higher concentration of fire retardant. It was also observed that the increase in the proportion of the fire retardant increased the time of burning, may be due to the compactness of the composite due to the presence of fire retardant as a filling material even though it was meant to reduce the rate of inflammability of the composite / Na presente pesquisa foram desenvolvidos comp?sitos com fibras da folha do abacaxizeiro (PALF - Pineapple Leaf Fiber), utilizando resina de poli?ster insaturado como matriz, incorporando retardante de chama em diferentes composi??es. As fibras da folha do abacaxizeiro foram obtidas na ramada 4 do munic?pio de Ielmo Marinho no Estado do Rio Grande do Norte. A resina de poli?ster insaturado e o catalisador foram comprados no com?rcio. O retardante de chama de alumina trihidratada (hidr?xido de alum?nio - Al(OH)3) foi doado pela empresa Alcoa Alum?nio S.A. e foi utilizado em propor??es de 20%, 40% e 60% do peso do material utilizado na fabrica??o dos comp?sitos. As PALFs foram tratadas com 2% de hidr?xido de s?dio, por 1 hora, para eliminar as impurezas superficiais tais como ceras, gorduras, pectinas e pectatos, para que houvesse uma melhor ades?o da matriz ?s fibras, bem como do retardante de chama. As mantas de fibras foram preparadas num preparador de manta por imers?o, desenvolvido no Laborat?rio de Engenharia T?xtil da UFRN. Os comp?sitos (300x300x3 mm) foram moldados por compress?o e as amostras (150x25x3 mm) para an?lise das propriedades foram cortadas, em diferentes posi??es da placa do comp?sito com aux?lio de uma m?quina de laser. As propriedades mec?nicas de tra??o e flex?o em tr?s pontos foram realizadas no CTG?s RN e no Laborat?rio de Metais e Ensaios Mec?nicos de Engenharia de Materiais da UFRN. Os testes da emiss?o de fuma?a e resist?ncia ao fogo foram realizados no Laborat?rio de Engenharia T?xtil da UFRN, utilizando a norma UL94. As amostras resultantes das propriedades mec?nicas foram avaliadas no MEV do N?cleo de Estudos em Petr?leo e G?s Natural da UFRN. Com base nas an?lises dos resultados nos ensaios mec?nicos, observou-se que o retardante de chama n?o tem influ?ncia significativa. Tamb?m observou-se que no ensaio de abosor??o de ?gua, quanto maior a concentra??o de retardante de chama, a quantidade de ?gua absorvida ? menor. No teste de inflamabilidade, observou-se que quanto maior a concentra??o de retardante de chama, maior o tempo de queima. Pode ser conclu?do que a presen?a de retardante de chama, al?m de atuar como inibidor de chama, tamb?m atua como uma carga que influ?ncia a compacta??o do comp?sito e desta forma reduz a taxa de queima

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