Abstract: This study aimed to evaluate the chemical composition of wood particles (control and treated), and the effects of thermal modification and adhesive levels on the wettability and biological resistance of particleboards made of sugarcane residue and bamboo (Dendrocalamus asper). Therefore, 75% bamboo particles and 25% sugarcane residue (bagasse) were used for producing the particleboards. The particles were treated at 220 °C for 3h35min. Urea formaldehyde (UF) adhesive was used in three solid contents (10%, 12% and 14%) based on the dry mass of the particles. The mat was cold pre-consolidated (pressure of 0,5 MPa for 5 min) and after hot consolidated (3,45 MPa, 180 ºC, 10 min). Water and ethylene glycol and two measurement times were used to measure the contact angle. Gloeophyllum trabeum and Rhodonia placenta (brown rot) and Trametes versicolor (white rot) fungi were used for the biological resistance test. There was a change in the chemical composition of the treated particles such as a reduction in the levels of lignin (bagasse and bamboo), total extracts and holocellulose (bagasse). The thermal treatment increased the final contact angles obtained with water. The particleboard surfaces were classified as non-wettable and partially wettable to the tested solvents. The thermal treatment provided biological resistance improvements in the particleboards to the tested fungi, being classified as very resistant to Rhodonia placenta, resistant to very resistant to Gloeophyllum trabeum, and moderate to resistant to Trametes versicolor.

Abstract: This evaluated the natural resistance of wood from seven Eucalyptus trees in field decay and soil bed tests. Two 12-year-old trees were randomly sampled per species, with 2,2 m logs being obtained from the basal section of each tree. The samples were taken in two positions in the radial direction of the stem (middle heartwood and transition zone; containing heartwood and sapwood). The field decay tests were installed in three municipalities in the southern state of Espírito Santo, and the soil utilized soil from the three field decay test areas. The field decay tests were evaluated after six, 12 and 18 months after installation and the soil bed tests after six months. The Scott-Knott test (p ≤ 0,05) was used in the analysis and evaluation of the tests. The sapwood-heartwood (transition region) exhibited the greatest mass losses for the field decay and soil bed tests. On average, for the soil bed test the lowest mass losses were observed for the soil of Vargem Alta (5,00 %), with greater mass losses observed for São José do Calçado (7,05 %) and Jerônimo Monteiro (9,90 %). In the field decay test the organisms present in the soil of São José do Calçado and related to the organic matter content Eucalyptus grandis and Eucalyptus saligna more intensely.

RESUMO Os produtos químicos não renováveis ainda são os mais utilizados para proteção da madeira, porém possuem aspectos negativos. Diversos problemas associados ao uso extensivo dessas substâncias são relatados, como a intoxicação de animais e plantas e contaminação ambiental. Isto tem levado à procura por métodos alternativos de controle que ocasionem menor impacto ao ambiente. Neste contexto, o uso de produtos naturais extraídos de diferentes plantas pode ser alternativa a esta atividade industrial. O objetivo desse trabalho foi avaliar a eficiência dos óleos de andiroba, copaíba e pinhão manso, puros ou enriquecidos com iodo (I2) para melhorar a resistência biológica da madeira de Pinus elliottii a fungos apodrecedores, causadores das podridões parda, branca e mole. Os óleos de andiroba e copaíba foram oriundos do estado do Pará e o de pinhão-manso da Paraíba. Foram realizados os ensaios de resistência ao apodrecimento acelerado em laboratório (fungos de podridão parda e branca) e ensaio de podridão mole. Na avaliação da eficiência, os óleos naturais foram empregados puros e enriquecidos com iodo sublimado. Foram avaliados os efeitos da volatilização e lixiviação na eficiência das soluções contra os fungos aprodrecedores. No ensaio biológico de apodrecimento acelerado, os óleos de andiroba e pinhão manso puros foram os menos eficientes no controle do fungo Trametes versicolor. No controle do fungo Postia placenta, a madeira tratada com o óleo de copaíba puro (situação normal) foi classificada como não resistente. No ensaio de podridão mole observou-se que com o aumento da concentração de iodo (I2) houve tendência de melhoria da resistência da madeira (situação normal).

ABSTRACT Non-renewable chemical products are still the most used for wood protection, however, they have negative aspects. Several problems associated with the extensive use of these substances have been reported, such as intoxication of animals and plants, and environmental contamination. This has led to a search for alternative methods of control that cause less impact on the environment. In this context, the use of natural products extracted from different plants can be an alternative to this industrial activity. The objective of this work was to evaluate the efficiency of andiroba, copaiba and jatropha oils, either pure or enriched with iodine (I2), to improve the biological resistance of Pinus elliottii wood to wood-decay fungi causing brown, white and soft rot. The andiroba and copaiba oils came from the state of Pará and the jatropha oil came from Paraíba. Thus, we performed resistance tests to accelerated decay (brown and white rot fungi) and soft rot tests in the laboratory. We used pure natural oils and those enriched with sublimated iodine in assessing efficiency. In turn, we evaluated the effects of volatilization and leaching on the efficiency of solutions against decaying fungi. Pure andiroba and jatropha oils were the least efficient in controlling the Trametes versicolor fungus in the accelerated decay biological assay. Moreover, the wood treated with pure copaiba oil (normal situation) was classified as non-resistant for controlling Postia placenta fungus. In the soft rot test, we observed that there was a tendency to improve the wood resistance (normal situation) with an increase in the iodine concentration (I2).

Abstract This research aims to evaluate the physico-mechanical properties of wood-plastic composites produced with recycled polyethylene terephthalate, high-density polyethylene, low-density polyethylene and polypropylene, and sawdust from the following species: Pinus caribaea, Pinus cubensis, Cedrela odorata, Talipariti elatum and Eucalyptus sp. Composites were obtained by extrusion with dimension of 1,000 × 250 × 16 mm (length × width × thickness), through six treatments. The following physico-mechanical properties were evaluated: density, moisture content, water absorption and thickness swelling, compression, static bending and traction. Treatment 6 obtained the best results, with 1,060 kg m-3 density, 5.23% moisture content, 0.32% water absorption, and 0.18% thickness swelling. Compressive strength was 138.10 MPa, static bending 18.53 MPa, and traction 29.4 MPa. The technology developed has prospects for large-scale production.

Resumo Resíduos de bambu (Bambusa vulgaris) foram utilizados como matéria-prima para a produção de carvão ativado (CA). Os materiais foram coletados e transformados em CA mediante processos de carbonização (500°C, 1,67°C min-1, 60 min) e ativação (800°C, 10°C min-1, 60 min) com CO2 (100 mL min-1). O material obtido (CA CO2) foi caracterizado pelo seu rendimento, análise elementar, teor de cinzas, área superficial (SBET), método titulométrico de Boehm, microscopia eletrônica de varredura e utilizado como adsorvente para remoção dos contaminantes azul de metileno e fenol. Os modelos de isotermas de Langmuir e de Freundlich foram selecionados para entender o processo de adsorção. O CA CO2 produzido apresentou rendimento de 21,6%, teor de carbono de 82,13% e SBET de 856,78 m2 g-1, apresentando uma remoção rápida e elevada capacidade de adsorção para o azul de metileno (298,82 mg g-1) e fenol (558,29 mg g-1).

Abstract Bamboo (Bambusa vulgaris) wastes were used as raw material for producing activated carbon. The materials were collected and turned into activated carbons by carbonization (500 °C, 1.67 °C.min-1, 60 min) and activation (800 °C, 10 °C.min-1, 60 min) processes with CO2 (100 mL.min-1). The obtained material (CO2 AC) was characterized by its yield, elemental analysis, ash content, surface area (SBET), Boehm titration method, scanning electron microscopy and used as adsorbent for removing the methylene blue and phenol contaminants. The Langmuir and Freundlich isotherm models were selected for understanding the adsorption process. CO2 AC produced showed yield of 21.6%, carbon content of 82.13% and SBET of 856.78 m2.g-1, presenting rapid removal and high adsorption capacity for methylene blue (298.82 mg.g-1) and phenol (558.29 mg.g-1).

ABSTRACT This work aimed to evaluate the biological resistance of Australian red cedar (Toona ciliata) and Eucalyptus woods to the Cryptotermes brevis (Kalotermitidae) dry wood termite species. The species used to evaluate natural resistance to insect attacks were Australian red cedar from 6 and 12-year-old plantations installed in the mountainous region of the Espírito Santo state, and commercial adult Eucalyptus sp. wood provided by a sawmill located in the South of Bahia state. Fitting and evaluation of the experiment followed the recommendations of the Institute for Technological Research of the State of São Paulo. The three woods differed as to their susceptibility to attack by dry wood termites when the damage caused in the samples was considered, with the most consumed species being the 12-year old Australian red cedar, while the Eucalyptus wood was less susceptible to damage.

ABSTRACT Natural products have been studied in order to ensure environmental sustainability, human health, and diminish the use of traditional products. The objective of this study was to evaluate the efficiency of pure andiroba (Carapa guianensis), copaiba (Copaifera langsdorffii) and jatropha (Jatropha curcas) oils and enriched with iodine (I2) on the biological resistance of Pinus elliottii wood to dry-wood termites (Cryptotermes brevis). The oils were enriched with 1%, 3%, and 5% of I2 and impregnated into the wood by cold immersion. The treated samples were subjected to volatilization and leaching. Volatilization and leaching did not affect the loss of mass caused by termites, except for treatments with pure and enriched with 1% iodine copaiba oil. Leached samples were more damaged. The addition of iodine to the oils resulted in a greater efficiency against termites. Andiroba (3% and 5% I2) and jatropha oils (5%) were the most efficient, providing total termite mortality.

ABSTRACT The objective of this work was to evaluate environmental effect on growth, wood basic density and anatomical characteristics of Eucalyptus grandis × Eucalyptus urophylla clones for pulp production. The studied clones were from 6.5-year-old plantations of Fibria Celulose company, located in two places: Nova Almeida (ES) and Posto da Mata (BA). The total and commercial heights, diameter at breast height (DBH), wood and bark volume (dendrometric characteristics), heartwood and sapwood percentages, wood basic density and wood fibers and vessels were evaluated. The heartwood and sapwood percentage and vessel frequency were the only characteristics not influenced by the growth site among the studied parameters. On the other hand, tree height (total and commercial) was considered the most influenced by the environment.

ABSTRACT The manufacture of forest products with high physical and mechanical properties contribute to the development of the forest industry in obtaining more resistant products with potential in the construction sector. In this context, to contribute to the study of reconstituted panels this article discusses the manufacture of panels reinforced with recycled thermoplastics (WPC), which had as raw material sawdust of Pinus caribaea and as recycled thermoplastics polyethylene terephthalate, low-density polyethylene and polypropylene. The panels were obtained by extrusion and developed in four treatments with different proportions of raw material. Thickness swelling rates of the manufactured WPC were evaluated by immersing them in water at room temperature and monitoring thickness changes for several weeks. A swelling model developed by Saeed Kazemi Najafi was used to study the thickness swelling process of WPC. The WPC were characterized by thickness swelling, apparent density, static blending, longitudinal compression and tensile strength. The treatment with 50% sawdust and blend of all thermoplastics (T5) showed a tendency to reduce the thickness swelling because it absorbs 0.28% of water and maintains the balance of water absorption in 16.2% the apparent density was 1206 kgm-3. For the mechanical properties, the static blending, longitudinal compression and tensile strength are around 24.6, 142.4 and 32.8 MPa, respectively. These characteristics make a treatment the best response. Hence, is suggested this board be used for structural applications, such as interior or exterior walls, since the water absorption index is low and high mechanical properties allow being more resistant.

RESUMO Neste estudo, avaliaram-se a penetração e a retenção do preservativo borato de cobre cromatado (CCB) em peças roliças de algaroba (Prosopis juliflora (Sw.) DC.) quando submetidas ao método de substituição da seiva. Foram aleatoriamente selecionados 16 fustes, os quais foram divididos em quatro grupos. O primeiro grupo foi submetido à solução preservante duas horas após o abate (situação denominada “normal”); o segundo grupo foi submetido à solução preservante 24 horas após o abate (situação denominada “posterior”); o terceiro grupo foi mantido imerso em água durante 15 dias antes de ser submetido à solução preservante (situação denominada “imersa”); o quarto grupo não foi submetido à preservação. Após o término do processo de imunização, foram retirados discos em três distintas posições de cada tronco (base, meio, topo) para a avaliação dos parâmetros de penetração e retenção. Para análise da penetração, utilizaram-se reações colorimétricas, sendo avaliados os elementos boro e cobre. As análises de retenção para os elementos cromo, cobre e boro foram realizadas por espectrofotometria. Utilizou-se o delineamento inteiramente casualizado em arranjo fatorial, com quatro repetições (peças roliças), considerando-se dois fatores: Situação e Posição. O fator Situação foi composto por três níveis (normal, posterior, imersa), assim como o fator Posição (base, meio, topo). O efeito dos fatores principais e suas interações, assim como a comparação de médias, foram analisados considerando-se 5% de probabilidade. Os resultados obtidos permitem concluir que peças mantidas imersas antes de serem submetidas ao tratamento preservativo apresentaram significativa melhoria de sua tratabilidade, mantendo uma distribuição uniforme dos elementos químicos ao longo do seu comprimento.

ABSTRACT In this study, penetration and retention of the preservative chromated copper borate (CCB) in round pieces of algaroba (Prosopis juliflora (Sw.) DC) were evaluated when subjected to the sap substitution method. Sixteen trunks were randomly selected and divided into four groups. The first group underwent preservative solution 2 hours after felling (called “normal”); the second group underwent preservative solution 24 hours after the cutting down (called “posterior”); the third group was kept immersed in water for 15 days before being subjected to the preservative solution (called “immersed”); the fourth group was not subjected to preservation. After the end of the preservation process, disks were obtained at three different positions of each trunk (base, middle and top) for the evaluation of the parameters of penetration and retention. For analysis of the penetration, colorimetric reactions were used as well as the reviews of the boron and copper elements. Analyses for retaining the elements chromium, copper, and boron were carried out by spectrophotometry. It used a completely randomized factorial design with four replications (round wood) considering two design factors: Situation and Position. The situation factor consisted of three levels (immediate, posterior, immersed), and the position factor (base, middle, top). The effect of the main factors and their interactions, along with the comparison of means, were analyzed considering 5% of probability. The results indicated that pieces that were kept submerged before being submitted to the preservative treatment showed significant improvement in their treatability, maintaining an even distribution of the chemical elements along its length.

Abstract: This study is a continuation of a previous study published in this journal, with the aim of evaluating the effect of the Brazilian industrial thermal modification process on some physical properties of Eucalyptus grandis juvenile wood. Flatsawn boards of juvenile wood were tested for four treatment levels: untreated and thermally modified wood at final cycle temperatures of 140 °C, 160 °C and 180 °C. Physical properties were assessed according to a standard of the Comisión Panamericana de Normas Técnicas and a method proposed by the specialized literature encompassing equilibrium moisture content (a measure of wood’s hygroscopicity), density (oven-dried and air-dried) and radial, tangential and volumetric swelling (from oven-dried to green moisture content). Thermally modified Eucalyptus grandis wood became less hygroscopic, more dimensionally stable (tangential and volumetric swelling) and less dense, even at the lowest temperature tested (140 °C), except for radial swelling, which did not differ from untreated wood.

RESUMO O carvão ativado (CA) é um produto essencial para remoção de contaminantes ambientais, entretanto os altos custos de produção limitam seu uso. Neste trabalho, foi produzido CA a partir de bambu mediante ativação físico-química simultânea direta (utilizando ácido fosfórico e vapor d’água), a 500 °C por 1 hora, para avaliar sua eficácia na adsorção do corante azul de metileno (AM). Estudos cinéticos e de equilíbrio de adsorção em sistema batelada foram realizados em temperatura ambiente (para avaliar a influência da adsorção do corante AM sobre o CA produzido) e os modelos de isotermas de Langmuir e de Freundlich foram selecionados para entender o processo de adsorção. O CA produzido apresentou um valor relativamente alto de área superficial igual a 1354,42 m² g-1. O tempo de contato preciso para o AM atingir o equilíbrio foi de 12 horas. O desempenho da adsorção foi melhor delineado pelo modelo dado pela isoterma de Langmuir, cuja capacidade máxima de adsorção foi de 374,75 mg g-1. E o fator adimensional RL revelou a natureza favorável do processo de adsorção nas condições realizadas. Os resultados obtidos neste estudo recomendam o uso do CA produzido a partir de bambu no tratamento de água contaminada pelo corante AM, mormente em concentrações maiores que os limites permitidos pela legislação. Finalmente, pesquisas complementares devem ser realizadas para aprimorar, ainda mais, a qualidade do material produzido.

ABSTRACT Activated carbon (AC) is an essential product for the removal of environmental contaminants, but the high production costs limit its use. In this work, AC was produced from bamboo through simultaneous direct physical-chemical activation (by using phosphoric acid and water steam), at 500 ºC for 1 hour, to evaluate its adsorption effectiveness for methylene blue dye (MB). Adsorption kinetic and equilibrium studies at batch system were realized at room temperature (to evaluate the adsorption influence of the MB dye over the produced AC) and the Langmuir and Freundlich isotherms systems were selected for understanding the adsorption process. The produced AC showed a relatively high value of surface area equal to 1354.42 m².g-1. The required contact time for the MB to reach equilibrium was 12 hours. The adsorption performance was better delineated by the Langmuir isotherm, which maximum adsorption capacity was of 374.75 mg.g-1. In addition, the RL dimensionless factor reveled the favorable nature of the adsorption process in the used conditions. The results obtained in this study recommend the use of the produced AC from bamboo in the treatment of the water contaminated by the MB dye, foremost in higher concentrations than limits admitted by the legislation. Finally, complementary researches must be conducted to improve, even more, the quality of the produced material.

Abstract Wood and thermoplastic waste can be used to produce new forest products with better properties and higher benefit. The objective of the research was to evaluate the fire retardant properties of wood plastic boards made from wood waste (sawdust) from different forest species (Pinus caribaea, Pinus cubensis, Cedrela odorata, Talipariti elatus and Eucalyptus sp.), recycled thermoplastics (polyethylene of low and high density, polyethylene terephthalate and polypropylene), chemical additives (calcium carbonate, stearic acid, calcium stearate, zinc stearate and coupling agent) and tetrabrik as flame retardant. The boards were produced on a laboratory scale and processed by extrusion. The flame retardant properties were evaluated by reaction and fire resistance tests according to the European Standard (UNE EN) 13823. The developed treatments showed good response to the reaction and resistance to fire; treatment 6 showed the best results. The extraction of the resin from pine wood allowed the boards to improve their fire retardant properties. The highest levels in terms of the effects of fire can be obtain by mixing all the raw materials in equitable proportions, which provide the boards with better properties. The proposed methodology for the production of wood plastic boards can be developed on a large scale by the board industry, given its low cost-quality-benefit. In this way, sustainable use of industrial waste and its conversion into useful materials for society can be achieved.

Resumen Los residuos de madera y termoplásticos pueden ser usados para producir nuevos productos forestales con mejores propiedades y mayor valor agregado. El objetivo de la investigación fue evaluar las propiedades ignífugas de tableros de madera plástica elaborados a partir de residuos madereros (aserrín) de diferentes especies forestales (Pinus caribaea, Pinus cubensis, Cedrela odorata, Talipariti elatus y Eucalyptus sp.), termoplásticos reciclados (polietileno de baja y alta densidad, tereftalato de polietileno y polipropileno), aditivos químicos (carbonato de calcio, ácido esteárico, estearato de calcio, estearato de zinc y agente de liga) y tetrabrik como retardante de llama. Los tableros fueron producidos a escala de laboratorio y procesados mediante extrusión. Las propiedades ignífugas fueron evaluadas mediante los ensayos de reacción y resistencia al fuego según indicaciones de la Norma Europea (UNE EN) 13823. Los tratamientos desarrollados mostraron buena respuesta en cuanto a reacción y resistencia al fuego; el tratamiento 6 mostró los mejores resultados. La extracción de la resina a la madera de las especies de pino permitió que los tableros mejoraran sus propiedades ignífugas. Los niveles más altos en cuanto a los efectos del fuego se pueden alcanzar mediante la mezcla de todas las materias primas en proporciones equitativas, las cuales aportan a los tableros mejores propiedades. La metodología propuesta para la producción de tableros de madera plástica puede ser desarrollada a gran escala por la industria de tableros, dado su bajo costo-calidad-beneficio. De esa forma se puede dar un uso sustentable a residuos industriales, propiciando su reconversión en materiales útiles para la sociedad.

Abstract The objective of this study was to evaluate the mechanical resistance and resistance to degrading agents in particleboard with eucalyptus wood residue and Urea-Formaldehyde, Phenol-Formaldehyde and Tannin-Formaldehyde adhesives at two temperatures (120 ºC and 140 ºC). The panels were produced in the dimensions of 40 cm × 40 cm × 1.25 cm (width, length and thickness, respectively); 10% and 20% of tannin (50% solution) was added to the pure adhesives. The following parameters were evaluated: Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) in static bending, internal bonding, screw withdrawal, resistance to rotting fungi and dry wood termite. MOR showed better results at 120 °C. None of the treatments reached the minimum standard for the MOE, contrary to the internal bonding. The Trametes versicolor fungus caused greater mass loss to the tested panels when compared to Postia placenta. The proportion of tannin (90:10) in the phenolic adhesive contributed to a decrease in the resistance of the panel to the dry wood termite.

Resumen El objetivo de este estudio fue evaluar la resistencia mecánica y la resistencia a agentes degradadores en tableros de partículas con madera de eucalipto con adhesivos a base de urea-formaldehído, phenol-formaldehído y tanino-formaldehído a dos temperaturas (120 °C y 140 °C). Las dimensiones de los tableros fueron 40 cm × 40 cm × 1.25 cm (ancho, largo y grosor, respectivamente); se agregó 10% y 20% de taninos (solución al 50%) a los adhesivos puros. Los parámetros evaluados fueron: módulo de ruptura (MOR), módulo de elasticidad en flexión estática (MOE), cohesión interna, extracción de clavos, resistencia a descomposición por hongos y a termitas de madera seca. El hongo Trametes versicolor causó mayor pérdida de masa a los tableros ensayados en comparación con la causada por Postia placenta. La proporción de taninos (90:10) en el adhesivo fenólico contribuyó a disminuir la resistencia del tablero al ataque de termitas de madera seca.

RESUMO Taninos da casca de eucaliptos foram obtidos por meio da extração com água sob adição de 8 % de Na2CO3 e a 4% de Na2SO4, com posterior formulação de adesivos. As propriedades adesivas foram avaliadas quanto a viscosidade, densidade, teor de sólidos, tempo de formação de gel e pH dos adesivos da acácia negra a 50%, ureia 100%, de tanino da casca de eucalipto extraído com Na2CO3 a 30% e de Na2SO4 a 50%, e ureia com taninos extraídos das cascas de eucalipto na relação de 90:10 e 80:20. Resíduos madeireiros de eucalipto (classificados em três classes de densidade: baixa, média e alta) foram colados a quente com adesivos tânicos e sintético. A resistência das juntas coladas foi determinada por meio de resistência ao cisalhamento e falha na madeira. Pode-se concluir que os adesivos compostos pelo tanino extraído com sulfato de sódio e com carbonato de sódio puros (100%) apresentaram características desejáveis para a produção de taninos, mas não o suficiente para sua utilização como adesivo em madeira em sua totalidade, podendo ser utilizado no enriquecimento de ureia-formaldeído na colagem da madeira. A maior resistência ao cisalhamento na madeira ocorreu na classe de densidade alta, para todos os adesivos empregados, enquanto que as maiores falhas na madeira na maioria dos adesivos testados ocorreram em madeira de baixa densidades.

ABSTRACT Tannins of eucalyptus bark were obtained by extracting with water under addition of 8% Na2CO3 and 4% Na2SO4. To determine the adhesive properties was evaluated the viscosity, density, solids, gel time, and pH of adhesive of black wattle 50%, urea 100%, tannin extracted from the eucalyptus bark with Na2CO3 30% and Na2SO4 50%, and urea with tannin extracted from the eucalyptus bark of ratio of 90:10 and 80:20. Waste eucalypts wood (density classified into three classes: low, medium and high) were glued to the hot tannic and synthetic adhesives. The resistance was determined by the glued joints shear strength and wood failure. It can be concluded that the adhesive compounds by tannin extracted with sodium sulphate and pure sodium carbonate (100%) had desirable characteristics for the production of tannins, but not enough for its use as adhesive wood in its entirety and it may be used in the urea-formaldehyde glue gem enrichment in the timber. The higher shear strength on wood occurred in the high density class for all adhesives used, while larger gaps in wood adhesives in most tests it occurred in the wooden low densities.