Navegando por Autor "Guimarães Júnior, José Benedito"

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Efeito da incorporação de casca de café nas propriedades físico-mecânicas de painéis aglomerados de Eucalyptus Erophylla S.T. Blake
(Editora UFLA, 2010-05) Mendes, Rafael Farinassi; Mendes, Lourival Marin; Guimarães Júnior, José Benedito; Mori, Fábio Akira; César, Antonia Amanda da Silva
Neste trabalho objetivou-se avaliar a influência da incorporação de casca de café nas propriedades físico-mecânicas de painéis aglomerados produzidos com Eucalyptus urophylla S.T. Blake. Os painéis foram produzidos com incorporação de 25, 50 e 75% de casca de café, em três teores da resina fenol-formaldeído (6, 9 e 12%) e 1% de parafina. A densidade nominal dos painéis foi de 0,7 g/cm3 e o ciclo de prensagem compreendeu uma pressão de 3,92 MPa e temperatura de 180oC por 8 minutos. Pelos resultados obtidos foi possível observar que: as propriedades físicas dos painéis aglomerados apresentam relação linear decrescente com o aumento do teor de resina, e crescente com a porcentagem de casca de café, apresentando maiores valores de absorção de água e inchamento em espessura. As propriedades mecânicas apresentam relação linear crescente com o aumento do teor de resina, e decrescente com a porcentagem de associação de casca de café. Do modo que a pesquisa foi conduzida, a incorporação da casca de café prejudica a qualidade dos painéis produzidos.
Eucalyptus wood and coffee parchment for particleboard production: physical and mechanical properties
(Editora UFLA, 2017-03) Scatolino, Mário Vanoli; Costa, Andrey de Oliveira; Guimarães Júnior, José Benedito; Protásio, Thiago de Paula; Mendes, Rafael Farinassi; Mendes, Lourival Marin
The wood panel industry is constantly growing, being necessary the innovation in technologies and raw materials to improve the quality of the final product. Considering the shortage and pressure to decrease the dependence of wood, there is an interest in other renewable materials such as agricultural wastes. Among these wastes, coffee parchment is one which deserves notoriety. An alternative use for coffee parchment could be for production of particleboard in association with wood particles. This study aimed to evaluate the feasibility of using coffee parchment for production of particleboard. The following percentages of wastes were used: 0, 10, 20, 30, 40 and 50% in association to eucalyptus wood. The panels were produced with 8% of urea formaldehyde (based on dry weight of particles). The pressing cycle consisted by: pre-pressing of 0.5 MPa for 10 minutes followed by pressing of 4.0 MPa, and temperature of 160° C for 15 minutes. The compaction ratio of particleboards produced using higher quantities of parchment improved the physical properties. The properties of Water Absorption (2 and 24 h) and Thickness Swelling (2 h) decreased with increasing percentage of coffee parchment. The Thickness Swelling (24 h) showed not significant effect with an increase of coffee waste. The Modulus of Elasticity for coffee parchment particleboards was in the range 646.49 ± 112.65 to 402.03 ± 66.24 MPa, while the Modulus of Rupture ranged from 8.18 ± 1.39 to 4.45 ± 0.75 MPa. The results showed that 10% of coffee parchment could be added for production of particleboards.
Performance of cross laminated timber panels made of Pinus oocarpa and Coffea arabica waste
(Editora UFLA, 2021) Furtini, Ana Carolina Corrêa; Santos, Carolina Aparecida dos; Garcia, Hudson Venâncio Silva; Brito, Flávia Maria Silva; Santos, Thalita Paula dos; Mendes, Lourival Marin; Guimarães Júnior, José Benedito
The growth of the civil construction sector, made necessary to develop alternative products made of sustainable materials. Within this context came the cross laminated timber panels (CLT), which are formed by gluing veneer arranged at 90°, which provide high strength and great versatility, as constructive elements. This research aimed to evaluate the chemical properties of the particles of both materials and evaluate the performance of CLT panels made with Pinus oocarpa and waste wood from Coffea arabica. The panels were made with three orthogonal layers with veneer of pine and coffee wood, using the phenol-formaldehyde (PF) adhesive with a spread rate of 0.35kgm-² and the hydraulic press with a pressure of 1,2×107 N.m-2for 15 min. The physical, mechanical properties, acoustic and thermal performance of the panels were evaluated. There was a significant difference for water absorption in 2 and 24 hours. The panels produced only with coffee wood waste showed the lowest water absorption rates, corresponding to 10.2 and 33.3%, in 2 and 24 hours. In relation to the MOE, the panels made with varied veneer were statistically equivalent to each other and the panels made of pine blades showed a MOE corresponding to 3,33×107 N.m-2. The same trend was observed for MOR, since the average value obtained for pine panels, corresponding to 1,35x108 N.m-2 was significantly higher. Panels made of coffee veneer and pine veneer showed no delamination. With regard to acoustic and thermal evaluation, all panels met the minimum requirements indicated in the standards, with emphasis on coffee wood waste, associated or not with pine wood.