Abstract This work aimed to evaluate the energy quality of wood and charcoal obtained from the stem and root of the genus Eucalyptus spp. From the wood, the physical, chemical and energetic properties were evaluated. For the charcoal produced in ovens of the carbonization furnaces model in the industry and produced in a muffle furnace, the physical, chemical and energetic properties were evaluated. Based on the analysis of technological properties, wood from the root has higher basic density (731.45 kg m-3) and lignin content (26.44%), however, the fixed carbon content and higher calorific value of the root (17.54% and 4547.75 kcal kg-1) were lower than for the stem wood (21.36% and 4730.82 kcal kg-1). It is recommended to use the wood from the root, both for direct burning and for the production of charcoal. The charcoal obtained in the industry, compared to that produced in muffle, presented higher energy quality.

Abstract The aimed to evaluate the properties of MDP and HDP panels, produced with pure Populus deltoides or in a mixture with Pinus taeda, together with urea-formaldehyde resin. The density and chemical properties of this wood with 8 and 12 years of age were determined, which were used for the production of panels with nominal density of 0.65 and 0.90 g.cm-3. Water absorption and thickness swelling tests were performed after 2 and 24 hours of immersion, as well as static bending and perpendicular tensile. Populus deltoides wood was classified as low-density in both ages and presented chemical properties similar to Pinus taeda. Mechanical properties obtained for the panels produced reached the minimum requirements values established by the standards NBR 14810-2 and ANSI A208.1, demonstrating the potential use of wood species for the production of MDP and HDP panels, at both ages studied and used pure or mixed with Pinus taeda wood.

ABSTRACT This study aims to evaluate the use of Hovenia dulcis wood to produce Edge Glued Panels – EGP. To this end, joints with dimensions of 5.0 × 31.0 × 2.5 cm (Width × Length × Thickness) were put together using polyvinyl acetate (PVAc) and emulsion polymer isocyanate (EPI) adhesives at a spread rate of 200 g.m-2 and the chemical characterization of the wood was performed. The strength of glued joints was evaluated through shear tests based on the procedures described by established standards. The results showed that the EPI adhesive achieved the best results in edge gluing to produce EGP. The use of PVAc adhesive did not show satisfactory results for edge gluing under these conditions. Hovenia dulcis wood is indicated for producing higher value-added wood products - (VAWP) for external use purposes.

RESUMO Neste estudo, foram produzidos compósitos com três tipos de matriz termoplástica e material celulósico em uma proporção de 40%. As três matrizes termoplásticas foram polietileno de alta densidade (HDPE), polipropileno (PP) e polietileno de baixa densidade (LDPE), e os materiais celulósicos foram farinha de madeira pura (Pinus taeda L) ou uma mistura de farinha de madeira e farinha de casca coco (Cocus nucifera L) em proporções iguais. O objetivo foi avaliar a influência da adição de casca de coco nas propriedades físico-mecânicas (densidade, resistência e rigidez) e a distribuição do material celulósico na matriz termoplástica dos compósitos. Verificou-se que os compósitos apresentaram uma distribuição satisfatória da farinha de madeira nas matrizes termoplásticas, mas a adição de casca de coco promoveu a formação de bolhas nas peças e, assim, interferiram com as propriedades do material. O uso de um agente de acoplamento promoveu melhor adesão interfacial (celulose - matriz termoplástica) nos compósitos com polietileno de alta densidade, seguidos do polipropileno e do polietileno de baixa densidade. Em geral, a adição de casca de coco causou uma diminuição de todas as propriedades em comparação com os compósitos produzidos com pinus. Além disso, as interações entre o tipo de termoplástico e o tipo de matriz celulósica foram confirmadas estatisticamente, e causaram variações nas propriedades estudadas.

ABSTRACT In this study, composites with three types of thermoplastic matrix and cellulosic material in a proportion of 40% were produced. The three thermoplastic matrices were high density polyethylene (HDPE), polypropylene (PP) and low density polyethylene (LDPE), and the cellulosic materials were pure wood flour (Pinus taeda L) or a mixture of wood flour and coconut shell flour (Cocus nucifera L) in equal ratios. The objective was to evaluate the influence of addition of coconut shell on the physico-mechanical properties (density, strength and rigidity) and the distribution of the cellulosic material in the thermoplastic matrix of the manufactured composites. It was found that the composites had a satisfactory distribution of wood flour in thermoplastic matrices, but the addition of coconut shell promoted bubble formation in the resulting pieces and, thus, interfered with the material properties. The use of a coupling agent promoted interfacial adhesion (cellulose - thermoplastic matrix), which was better in high density polyethylene composites, followed by polypropylene and low density polyethylene. In general, the coconut shell addition caused a decrease of all properties compared to composites made with Loblolly Pine. In addition, the interactions between thermoplastic type and cellulosic matrix type have been statistically confirmed, which caused variations in the studied properties

Este trabalho teve como objetivo estudar a relação da velocidade de avanço de um modelo de serra fita horizontal na qualidade final das lamelas de quatro espécies de madeira utilizadas na produção de pisos engenheirados: jatobá (Hymenaea courbari L.), muiracatiara (Astronium lecointei), amendoim (Pterogyne nitens) e sucupira (Bowdichia nitida). Foram estudadas as distribuições das espessuras das lamelas com relação à velocidade de avanço, considerando-se o tipo de madeira, a especificação do controle de qualidade e a existência de marcas na superfície. Os resultados mostraram que o amendoim apresentou maior aproveitamento na produção de lamelas, enquanto que o jatobá foi a espécie que sofreu maior perda no processo de produção. A velocidade de avanço que apresentou os menores índices de desclassificação de lamelas foi de 8 m/min, sendo a mais indicada para produção de lamelas.

In this research, we aimed to study the forward speed rate (feed rate) of a horizontal band saw model in the final quality of the lamellae from four wood species used in the production of engineered flooring, Jatoba (Hymenaea courbaril L.) Muiracatiara (Astronium lecointei), Amendoim (Pterogyne nitens ) and Sucupira (Bowdichia nitida). The distributions of the lamellae thicknesses were studied with respect to forward speed, considering the type of wood, specification of quality control, and existence of surface markings. Results showed that the Amendoim presented greater benefits to the production of lamellae, whereas the Jatoba was the species that showed the greatest loss during the production process. The feed rate of 8 m/min presented the lowest declassification of lamellae, being the most suitable for engineered wood flooring production.