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Agglomerated cork composites production has been arising as an alternative eco-friendly to cork stoppers use and attracts interest to create sustainable products and materials. A cork-bamboo-latex composite was developed by compression-molding and the interaction between three composite interfaces as well as their mechanical properties were evaluated by density measure, immersion test, FTIR, compression test, and microbial analysis aiming to produce an alternative material to wine closures. The results obtained were compared between the composite produced and the commercial agglomerated cork stoppers. It was possible to observe that the cork-bamboo-latex composite produced exhibited a good adhesion of all components and similar characteristics. However, it presented a slight increase in the density (from 0.37 g/cm3 to 0.65 g/cm3) and Young's modulus (from 0.033 MPa to 0.037 MPa) producing a stiffer material mainly due to bamboo presence. The migration of the stopper components (cork, bamboo, or latex) for the wine was not detected, as well as there was no visible interaction between wine and composite. In this work, the cork-bamboo-latex stopper fabricated presents a potential application as an alternative material to wine stoppers and stimulates the production of a sustainable material.

Se identificó la influencia del tratamiento térmico en la obtención de compuestos tánicos condensables a partir de residuos de corteza de Pinus spp para la producción de adhesivo. Los tratamientos térmicos fueron: (a) corteza sin tratamiento térmico (testigo); (b) corteza expuesta a 60 °C durante 50 h en seco; (c) corteza expuesta a 120 °C durante 10 h en vapor; (d) corteza adherida al tronco expuesta a 120 °C durante 10 h en vapor. Para su caracterización química, la corteza fue molida y clasificada. Se extrajeron los compuestos tánicos mediante reflujo con agua destilada durante 2 h; se adicionaron sales de carbonato de sodio y sulfito de sodio, ambos a 5% en relación con la masa seca. Para el testigo fueron evaluadas las propiedades del tanino comercial de Acacia mearnsii (acacia negra). El proceso de extracción de taninos fue realizado en autoclave y se evaluaron las siguientes propiedades: viscosidad, pH, tiempo de formación de gel, contenido de sólidos y densidad. Tanto la corteza expuesta a 120 °C durante 10 horas en vapor como la adherida al tronco sometida a 120 °C a vapor durante 10 h, para ambas sales, exhibieron los mayores rendimientos de taninos. Los extractos tánicos obtenidos a partir de carbonato de sodio presentaron una estructura alcalina, alta viscosidad y menor tiempo de formación de gel. Sin embargo, los extractos obtenidos a partir de sulfito de sodio proporcionaron un carácter ácido y contenido de sólidos próximos a los encontrados en los extractos tánicos acuosos obtenido de la acacia negra.

This study aimed to analyze the glue line thickness effect and its relation with the density and anatomical characteristics of eucalyptus wood. Thus, the thickness of main and secondary glue lines was measured as well as their interaction with the apparent density of elements glued with resorcinol-formaldehyde (RF) and castor oil polyurethane (CP) adhesives. Anatomical wood characterization of Eucalyptus grandis × Eucalyptus urophylla was performed by correlating glue line thickness. According to normative instruction, specimens were produced for delamination tests. The experiment was conducted in a completely random 2 × 2 design factorial scheme (two classes of wood apparent density and two adhesives). Pearson correlation (t < 0,01) was performed among variables. It was found that there was adhesive penetration into vessels and rays of wood. Glue line thickness was higher in woods with density higher than to 580 kg/m3 glued with RF adhesive. There was a low correlation between wood density and vessel diameter to main and secondary glue lines (t < 0,01)

The main goal of this study was to analyze glue line on eucalyptus wood. In order to do that, thickness of main and secondary glue lines were measured as well their interaction with apparent density of elements glued with resorcinol-formaldehyde (RF) and castor polyurethane (CP) adhesives. Anatomical wood characterization of Eucalyptus grandis × Eucalyptus urophylla was performed by correlating glue line thickness. According to normative instruction, specimens were produced for delamination tests. The experiment was conducted in a completely random 2 × 2 design factorial scheme (two classes of apparent density and two adhesives). Pearson correlation (t < 0.01) was performed among variables. It was found that there was adhesive penetration into wood pots and rays. Glue line thickness was higher in woods with density higher than 0.58 g cm−3 glued with RF adhesive. There was low correlation among density, vessel diameter, main and secondary glue lines (t < 0.01).

The objective of this work was to evaluate the influence of different useful areas provided by the planting spacings (3 × 1, 3 × 2, 3 × 3, 3 × 4 m) on the production and permeability of heartwood and sapwood of Eucalyptus grandis and Eucalyptus grandis × Eucalyptus urophylla clones at 4 years old. Regardless of the clone, there was no effect of planting spacing on the heartwood/sapwood relation and wood permeability. All clones showed a heartwood decrease with increased height, regardless of planting spacing, and E. grandis (B) was the only one that had its heartwood percentage positively and significantly correlated with the dendrometric variables (DBH and commercial height). The use of the dymethil yellow compound was indispensable in defining the heartwood and sapwood regions in the samples from 50% of the stem height. The heartwood permeability was low in all evaluated clones, suggesting vessel obstruction by tyloses or other deposits, while sapwood permeability reached 405.4 cm3/cm.atm.s. RESUMO O objetivo deste trabalho foi avaliar a influência de diferentes áreas úteis proporcionadas pelos espaçamentos de plantio (3 × 1, 3 × 2, 3 × 3, 3 × 4 m) na produção e na permeabilidade do cerne e do alburno da madeira de clones de Eucalyptus grandis e Eucalyptus grandis × Eucalyptus urophylla, aos 4 anos de idade. Independente do clone, não houve efeito do espaçamento de plantio na relação cerne/alburno e na permeabilidade da madeira. Todos os clones apresentaram um decréscimo na quantidade de cerne com o aumento da altura do fuste, independentemente do espaçamento de plantio, e o E. grandis (B) foi o único que a percentagem de cerne correlacionou-se positiva e significativamente com as variáveis dendrométricas (DAP e altura comercial). O uso do composto dymethil yellow foi indispensável na demarcação das regiões do cerne e do alburno nas amostras a partir de 50% da altura do fuste. A permeabilidade do cerne foi baixa em todos os clones avaliados, sugerindo obstrução dos vasos por tilas ou outras substâncias, enquanto a permeabilidade do alburno atingiu 405,4 cm3/cm.atm.s.

This study aimed to evaluate the resistance of medium density particleboard (MDP) made with ligno-cellulosic agro-industrial wastes to Brunneoporus malicola (≈Gleophyllum trabeum) and Trametes versicolor fungi and Cryptotermes brevis and Nasutitermes corniger termites. The panels were produced by compression, with different proportions of eucalypt sawdust, macadamia nut carpel, papaya stalk and coffee husks (10%, 20% and 30% each one and the control - 100% eucalypt sawdust) and bonded with urea-formaldehyde (UF) and tannin-urea-formaldehyde (TUF). The fungi and termite tests were performed in conformity the specific standards of wood and wood-based materials biological resistance. The resistance of each treatment was evaluated in terms of the composite mass loss and mortality for termite. All treatments submitted to the attack of Brunneoporus malicola and Tramites versicolor fungi were classified as moderately resistant or no resistant, no statistical difference. Highlight for 30% macadamia nut carpel with less mass loss, 42.28% and 43.58% in the UF and TUF panels, respectively. There were no statistical differences for mass loss and mortality between treatments and adhesives to dry-wood termites; treatment with 10% and 30% macadamia nut carpel showed greater mass loss (0.681 g) and mortality (56.50%), respectively. In general, all treatments showed low resistance to fungi and for dry-wood termite attack good resistance, indicating these case biological properties of the panels. The panels produced did not allow resistance to attack of Nasutitermes corniger termite.