Abstract In search of new materials from industrial waste, aiming at cost, efficiency and reduction of environmental liabilities, this study aimed to evaluate the physical, mechanical, acoustic and thermal characteristics of sandwich panels produced with sheets of Schizolobium amazonicum (paricá) and egg carton core made of cardboard, glued with adhesive phenol formaldehyde (FF), urea formaldehyde (UF) and interleaved the sheets glued with both. The panels were evaluated through thermal, acoustic, physical and mechanical tests. The FF and UF adhesives influenced the physical-mechanical properties of the panels. For thermal conductivity and thermal resistance, it was found that all panels met the normative requirements of NBR 15220 (ABNT, 2005) with emphasis on panels produced with FF. Therefore, the use of paricá sheets 32x12x0.2 cm (length, width and thickness, respectively) and egg box as a core with adhesive, proved to be promising for some uses in civil construction, in addition to adding value to the egg crate residues as thermal and acoustic insulators, can minimize the disposal of raw material in the environment.

Resumo Em busca de novos materiais a partir de resíduos industriais, visando ao custo, à eficiência e à redução do passivo ambiental, este trabalho teve como objetivo avaliar as características físicas, mecânicas, acústicas e térmicas de painéis sanduíche produzidos com lâminas de Schizolobium amazonicum (paricá) e núcleo de caixa de ovos feitos de papelão coladas com o adesivo fenol-formaldeído (FF) e com o adesivo ureia-formaldeído (UF), intercalando-se estas com lâminas coladas com ambos (FF+UF). Os painéis foram avaliados por meio de ensaios térmicos, acústicos, físicos e mecânicos. Os adesivos FF e UF influenciaram nas propriedades físico-mecânicas dos painéis. Para a condutividade térmica e resistência térmica, verificou-se que todos os painéis atingiram as exigências normativas da NBR 15220 (ABNT, 2005), com destaque para os painéis produzidos com FF. Sendo assim, a utilização das lâminas de paricá de 32x12x0,2 cm (comprimento, largura e espessura respectivamente) e de caixa de ovo como núcleo com adesivo se mostrou promissora para algumas aplicações na construção civil, além de agregar valor aos resíduos de caixa de ovo como isolantes térmicos e acústicos, por minimizar o descarte de matéria-prima no meio ambiente.

Abstract: This work aimed to evaluate the physical-mechanical properties of Pinus oocarpa wood agglomerated panels produced with different levels (0 %, 25 %, 50 %, 75 % and 100 %) of wood replacement with bean residues. For this purpose, Pinus oocarpa wood and the agricultural residue were reduced into particles and their properties of apparent density, extractives, lignin and ash content of these raw materials were determined. Then, the particles were dried to a 3 % humidity and granulometrically selected to produce panels with a density of 0,60 g/cm3. These particles were bonded using 12 % urea-formaldehyde adhesive, pressed, following normative dimensions (250 mm x 250 mm x 15 mm (width, length, and thickness)), and kept in a climate-controlled environment (20 ºC ± 2 ºC and 65 % ± 5 % RH) until the physical and mechanical tests were carried out. The research results indicated that the particles from bean residues in comparison with Pinus oocarpa wood, presented low density, lignin and holocellulose values, and higher extractives data. Furthermore, regarding the characterization of the panels, there was a trend towards uniformity in the apparent density values, an increase in the properties of compact ratio, water absorption and thickness swelling, and a decrease in their mechanical properties associated with the increase in the by-product addition to the panels. Therefore, new studies are necessary, seeking a larger study and greater knowledge of the addition effects of bean residues in particulate panels, aiming the dissemination of this sustainable process on large scale.

ABSTRACT Despite the increasing use of plaster as a construction material, due to its numerous advantages when compared to cement, its use is still restricted, because of its low mechanical resistance and high solubility in water. In this context, research has been carried out related to the addition of nanomaterials to improve the mechanical and physical properties of plaster in civil construction. A highly available, low-cost nanomaterial with excellent properties is nanotalc. In this work, nanocomposites with dimensions of 40 × 40 × 160 mm were produced with ultrafine micronized nanotalc replacing plaster in proportions of 0%; 0.5%; 1%; 1.5% and 2%. The physical and mechanical properties of the nanocomposites were evaluated according to standards. The nanocomposites produced with 1% nanotalc showed satisfactory results for physical and mechanical properties, with an increase of 1.8% in apparent density and 24.12% in compressive strength, and a decrease in water absorption of 6.23%, compared to the composite without the incorporation of nanotalc. The production of nanocomposites with the incorporation of 1% nanotalc is viable and shown to be promising, presenting potential for application as linings and internal partitions, since they showed low water absorption due to the hydrophobicity of nanotalc.

Abstract Peanut crop waste (hulls), which have a chemical composition similar to wood, can be considered as a source of industrial raw material for the production of particleboard, provided that they are of similar quality to wooden panels. The present study aimed to produce and evaluate the physical and mechanical properties of medium density particleboards made of peanut hulls and pine wood particles bonded with urea-formaldehyde adhesive. The panels did not present satisfactory dimensional stability. The mechanical properties were significantly reduced with the addition of peanut hulls. In general, peanut hulls did not represent a good alternative to be used as a source of raw material for the production of particleboard. The inclusion of new parameters in the production process would be essential to improve the technological properties, such as: new particle geometries, use of paraffin, particle treatments and inclusion of denser species in the composition of the panels.

RESUMO Essa pesquisa objetivou avaliar o potencial do bambu Bambusa tuldoides como reforço na matriz de gesso. Foi determinada a densidade básica, dimensões de fibras e constituição química da matéria-prima. Foram produzidos compósitos com substituição em volume da pasta de gesso por 0, 5, 10, 15, 20, 25 e 30% de bambu com uma relação água/gesso de 1:1. Para a caracterização mecânica dos compósitos foram realizados ensaios de flexão estática, compressão e densidade aparente. Os valores obtidos na avaliação da fibra apresentaram valores próximos à literatura. Na caracterização dos compósitos todas as propriedades tiveram regressão quadrática significativa e foi possível verificar o comportamento similar entre propriedades mecânicas e a densidade. Na densidade ocorreu um aumento do seu valor até a porcentagem de 17,41% que pode ser justificado devido à absorção da água pela fibra decorrente da presença de pontuações, o que gera uma diminuição na relação água gesso e um aumento da densidade. Já o decréscimo da densidade a partir de 17,41% está relacionado com a grande quantidade de fibras presente que ficam emaranhadas e causam espaços vazios já que a pasta de gesso não consegue infiltrar nesses locais. Na compressão, as porcentagens entre 3,37 e 26,19% são os que atenderam as exigências normativas (maior que 2 MPa), e na flexão as porcentagens entre 0 e 27,23% são as que estão em conformidade com a norma (maior que 1 MPa). Os resultados mostraram que a utilização do bambu Bambusa tuldoides como reforço é viável entre as porcentagens 3,37 e 26,19% para atender todas as exigências normativas.

ABSTRACT This research aimed to evaluate the potential of Bambusa tuldoides as reinforcement in the plaster matrix. The basic density, fiber dimensions and chemical constitution of the raw material were determined. Composites were produced with volume replacement of gypsum paste by 0, 5, 10, 15, 20, 25 and 30% of bamboo with a water / gypsum ratio of 1: 1. For the mechanical characterization of the composites, static bending, compression and bulk density tests were performed. The values obtained in the fiber evaluation presented values close to the literature. In the characterization of composites all properties had significant quadratic regression and it was possible to verify similar behavior between mechanical properties and density. In density there was an increase of its value up to the percentage of 17.41% that can be justified due to the absorption of water by the fiber due to the presence of scores, which generates a decrease in the water plaster ratio and an increase in density. The decrease in density from 17.41% is related to the large amount of fibers present that get tangled and cause voids since the plaster paste cannot infiltrate these places. In compression, the percentages between 3.37 and 26.19% are those that met the normative requirements (greater than 2 MPa), and in flexion the percentages between 0 and 27.23% are those that comply with the standard (greater than 1 MPa). The results showed that the use of Bambusa tuldoides as reinforcement is viable between 3.37 and 26.19% to meet all regulatory requirements.

RESUMO Este trabalho teve como objetivo produzir e caracterizar compósitos à base de gesso reforçados com partículas de resíduo de cacau como forma de agregar valor a esse subproduto agrícola e criar um material inovador. Para a produção dos compósitos foram utilizados gesso fino para fundição e partículas de resíduo de cacau. As proporções de reforço inseridas foram de 0,0%; 2,5%; 5,0%; 7,5% e 10,0% em substituição a massa de gesso. Para a produção dos compósitos foram utilizadas fôrmas de madeira com dimensões de 40 x 40 x 160 mm. Foi realizada análise da composição química do resíduo de cacau para determinação dos teores de extrativos totais, cinzas, lignina e holocelulose. Os compósitos foram avaliados nos ensaios físicos, mecânicos, térmico e acústico. Constatou-se que, houve melhorias nas propriedades físicas com o acréscimo de reforço tornando o material mais leve, visto a redução da densidade (1190,69 a 1138,92 kg/m³), e proporcionando a diminuição da higroscopicidade, com teores de umidade decrescendo de 7,74 a 4,01% e de absorção de água decrescendo de 18,37 para 5,28%. Da mesma forma, a resistência térmica aumentou gradativamente ao longo dos tratamentos com valores de 1,90 a 2,41 K.m/W e o isolamento acústico foi maior nos compósitos em comparação com o gesso puro, embora não tenha havido linearidade entre os tratamentos. Já para as propriedades mecânicas, houve diminuição de resistências tanto à flexão (3,60 a 0,84 MPa) quanto à compressão (4,43 a 1,73 MPa). Foi concluído que o resíduo de cacau apresenta potencialidade para ser utilizado no compósito tendo em vista que a inclusão de até 8,15% do mesmo atendeu a normatização em todos os ensaios realizados. Isso fomenta a ideia de que os resíduos lignocelulósicos são alternativas promissoras para criação de materiais de alto valor agregado.

ABSTRACT This work aimed to produce and characterize gypsum-based composites reinforced with cocoa waste particles as a way to add value to this agricultural by-product and create an innovative material. For the production of composites, thin plaster for casting and particles of cocoa waste were used. The reinforcement proportions inserted were 0.0%; 2.5%; 5.0%; 7.5% and 10.0% replacing plaster mass. For the production of composites, wooden molds with dimensions of 40 x 40 x 160 mm were used. Analysis of the chemical composition of the cocoa waste was performed to determine the levels of total extracts, ash, lignin and holocellulose. The composites were evaluated in physical, mechanical, thermal and acoustic tests. It was found that there were improvements in physical properties with the addition of reinforcement making the material lighter, given the reduction in density (1190.69 to 1138.92 kg/m³), ??and providing a decrease in hygroscopicity, with moisture levels decreasing from 7.74 to 4.01% and water absorption decreasing from 18.37 to 5.28%. Likewise, the thermal resistance gradually increased over the treatments with values ??from 1.90 to 2.41 K.m/W and the acoustic insulation was higher in composites compared to pure plaster, although there was no linearity between treatments. As for the mechanical properties, there was a decrease in resistance both to flexion (3.60 to 0.84 MPa) and to compression (4.43 to 1.73 MPa). It was concluded that the cocoa waste has the potential to be used in the composite considering that the inclusion of up to 8.15% of the same met the standard in all tests performed. This promotes the idea that lignocellulosic waste is a promising alternative for creating materials with high added value.

ABSTRACT Efforts have been done in order to decrease the human dependence on petroleum materials. This idea can be applied for wood adhesives and wood products. This study proposes to evaluate laminated veneer lumber (LVL) panels of Hevea brasiliensis produced with castor oil-based polyurethane and resorcinol formaldehyde in different grammages. Six rubber tree (12 years old) with diameters at breast height (DBH) > 25 cm were harvested to generate veneers (500 x 500 x 2 mm; length, width, and thickness, respectively) for the panels production. The veneers were pre classified by a non-destructive impulse excitation method (Sonelastic system). Seven veneers were arranged in the same grain direction to produce each LVL. The following grammages were used for each adhesive type: 240, 280 and 320 g.m-². The volumetric swelling of the panels, glue line strength under dry, wet and post-boiling conditions, and stiffness and strength in static bending tests in flatwise and edgewise positions were evaluated. The glue line was evaluated by optical microscopy. The panels with grammages of 240 g.m-² had the highest volumetric swelling for both adhesives. As the grammage increased from 240 to 280 g.m-², the panel volumetric swelling decreased 32.53% for the resorcinol formaldehyde adhesive and 21.42% for the castor oil-based polyurethane adhesive. The panels glued with the vegetal polyurethane adhesive presented the best results for shear strength in the glue line. No significant statistical differences were found between the compositions for static bending. The results indicate that rubber wood glued with vegetal polyurethane has the potential to be used for production of LVL panels and consequently replace the petroleum based adhesives.

ABSTRACT The aim of this work was to evaluate the physical and mechanical properties of particleboards using particles from wood shaving at three urea-formaldehyde adhesive contents: 6, 9 and 12% (dry mass basis). The particleboards were produced with nominal density of 0.70 g.cm-3, pressing cycle with temperature of 160 °C, pressure of 3.92 MPa and time of 8 minutes. The properties of water absorption (WA), thickness swelling (TS), both after 2 and 24 hours, apparent density, compression ratio, perpendicular traction, modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending, Janka hardness and screw withdrawal resistance were evaluated. The results of the tests indicated that with the increase of the adhesive content from 6 to 12%, there was no significant statistical difference for the average values of apparent density and compression ratio, being 0.621 g.cm-3 and 1.234, respectively, and the WA and the TS are decreased after 2 and 24 hours. There was a gain of 93% for the MOR property and 64% for the MOE property with the increase of the adhesive content. For perpendicular traction, the highest mean value was 0.67 MPa, referring to the panels with 12% of adhesive. For Janka hardness, the treatments with contents of 9 and 12% of adhesive presented the highest average values being of 21.60 and 25.26 MPa, respectively. In general, the use of wood shavings is feasible for the production of particleboards with a 12% adhesive content.

ABSTRACT The aim of this study was to evaluate the properties of Hevea brasiliensis wood wastes for production structural pieces of glued laminated (glulam) timber. Three trees with age close to 25 years and diameter at breast height (DBH) higher than 500 mm were obtained. The basic density of the wood were quantified, as well as the stiffness and the strength in static bending, shear strength and parallel compression to grain and hygroscopic equilibrium moisture. The beams of glulam were evaluated according to the modulus of elasticity (MOE), modulus of rupture (MOR) and delamination. Due to the bending properties MOR (75.14 MPa) and MOE (8166.79 MPa), as well as the shear strength (12.29 MPa) obtained, was concluded by the suitability of the rubber wood for the production of glulam beams. The composite beams presented values of MOR (75.14 MPa) and MOE (8166.79 MPa) compatible with species traditionally used in the production of glulam beams. The adhesive bond quality was verified by the delamination test, presenting delamination of 4.95 %, indicating its use for internal and external environments.

RESUMO As embalagens multicamadas são utilizadas por um período de tempo bastante curto gerando um volume de descarte elevado. Por serem formadas por diferentes materiais devido suas diversas camadas, sua reciclagem é dificultada. Sendo assim, são importantes novas aplicações para essas embalagens pós-consumo, como por exemplo o seu reaproveitamento em compósitos. Neste contexto, o objetivo deste trabalho foi desenvolver e caracterizar compósitos à base de gesso reforçados com embalagens multicamadas trituradas. As proporções utilizadas para a incorporação dos reforços foram de 0%, 7,5%, 15%, 22,5% e 30% em substituição ao gesso. Foram produzidos corpos de prova (três repetições por tratamento) para avaliação das propriedades de absorção de água, umidade, massa específica aparente, compressão e flexão estática, os quais foram confeccionados com dimensões de 40 x 40 x 160 mm. Para o ensaio térmico, as dimensões foram de 200 x 200 x 20 mm. Os reforços adicionados levaram a um aumento em umidade e absorção de água, enquanto que, para massa específica aparente, condutividade térmica, resistência à flexão, resistência à compressão e rigidez na compressão houve decréscimo. A incorporação de embalagens multicamadas em compósitos de gesso mostrou ser uma alternativa viável, visto que, além de aplicar a logística reversa reutilizando estas embalagens que muitas vezes são descartadas no meio ambiente de maneira inadequada, gerando diversos impactos, ainda melhorou a propriedade térmica dos compósitos e diminuiu a densidade destes. Ademais, todas as porcentagens atenderam a normatização para resistência à flexão, e para a resistência à compressão, apenas a substituição de 30% não atendeu a normativa.

ABSTRACT The multilayer packages are used for a very short time generating a high discard volume. Because they are formed by different materials due to their several layers, their recycling is difficult. Therefore, new applications for these post-consumer packages are important, such as their reuse in composites. In this context, the objective of this work was to develop and characterize plaster based composites reinforced with crushed multilayer packages. The proportions used to incorporate reinforcements were 0%, 7.5%, 15%, 22.5% and 30%, replacing gypsum. Test specimens (three replicates per treatment) were produced to evaluate the properties of water absorption, moisture, apparent specific mass, compression and static bending, which were made with dimensions of 40 x 40 x 160 mm. For the thermal test, the dimensions were 200 x 200 x 20 mm. The added reinforcements led to an increase in moisture and water absorption, whereas, for apparent specific mass, flexural strength, compressive strength and stiffness in compression there was decrease. The incorporation of multilayer packages into plaster composites proved to be a viable alternative, since in addition to applying reverse logistics reusing these packages that are often discarded in the environment in an inadequate manner, generating several impacts, it also improved the thermal properties of the composites , their density decreased, all percentages complied with normalization for flexural strength, and for compression strength, only the 30% insertion did not meet the standards.

RESUMO A soldagem de aços inoxidáveis duplex é uma operação crítica, devido aos ciclos térmicos aos quais o material é submetido, que podem favorecer a precipitação de fases deletérias. Nesse contexto, objetivo dessa pesquisa é analisar a influência da energia de soldagem na susceptibilidade à formação de fase sigma no aço duplex SAF2205. As chapas de SAF2205 foram soldadas pelo processo de soldagem GMAW, variando a energia de soldagem em 0,5kJ/mm, 1,0kJ/mm, 1,5 kJ/mm. O material foi analisado por microscopia óptica, DRX e microdureza Vickers. A análise da microestrutura das chapas evidenciou que quanto maior o aporte térmico utilizado na soldagem, maior é a quantidade de austenita e maior o tamanho do grão austenítico e ferrítico. Por meio do perfil de microdureza verificou-se que ocorre a redução da dureza na ZTA. Através do DRX foi determinada a presença de fase sigma nas regiões de solda para amostras soldadas com energia de soldagem de 1,0kJ/mm e 1,5 kJ/mm. Concluiu-se que pode-se utilizar nos processos de soldagem GMAW de aços inoxidáveis duplex SAF2205 com 4 mm de espessura aporte térmico próximo de 0,5 kJ/mm quando o objetivo for evitar a formação de fase sigma e aproximadamente igual a 1,5 kJ/mm quando o objetivo for manter percentual das fases na ZTA e ZF próximo ao do metal.

ABSTRACT Welding of duplex stainless steels is a critical operation, due to the thermal cycling to which the material is subjected, which can favor the precipitation of deleterious phases. The purpose of this research is to analyze the influence of welding energy on susceptibility to sigma phase formation in SAF2205 duplex steel. The SAF2205 sheets were welded by the GMAW welding process, varying the welding energy by 0.5 kJ/mm, 1.0 kJ/mm, 1.5 kJ/mm. The material was analyzed by optical microscopy, XRD and Vickers microhardness. The analysis of the microstructure of the plates showed that the higher the thermal input used in the welding, the greater the amount of austenite and the larger the size of the austenitic and ferritic grains. By means of the microhardness profile it was verified that the reduction of the hardness in the ZTA occurs. Through the XRD, the presence of sigma phase was determined in the weld regions for samples welded with welding energy of 1.0 kJ/mm and 1.5 kJ/mm. It was concluded that in the GMAW welding processes of SAF2205 duplex stainless steels with a 4 mm thick thermal input close to 0.5 kJ/mm when the objective is to avoid the formation of sigma phase and approximately equal to 1.5 kJ/mm when the objective is to maintain percentage of the phases in the ZTA and ZF next to the metal.

RESUMO A madeira laminada colada (MLC) é um material compósito obtido a partir da colagem de lâminas de madeira dispostas com as fibras paralelas entre si. O objetivo deste trabalho foi avaliar a influência do número de lâminas no comportamento mecânico de MLC de Toona ciliata produzidas com adesivo poliuretano de base vegetal. As vigas de MLC foram produzidas com lamelas nas dimensões de 6,0 x 1,5 x 120,0 cm, sendo confeccionadas 3 vigas por tratamento, os quais foram estruturalmente compostos por 5, 7 e 9 lâminas. Foi utilizado o adesivo poliuretano à base de óleo de mamona, sendo aplicada gramatura de 350 g m-². Para a caracterização tecnológica da madeira determinou-se a umidade na base seca, densidade aparente, caracterização química, resistência a compressão paralela às fibras, cisalhamento e os módulos de elasticidade (MOE) e ruptura (MOR) no ensaio de flexão estática. Enquanto para as vigas de MLC foram determinadas as propriedades de módulo de elasticidade (MOE), módulo de ruptura (MOR), resistência ao cisalhamento, delaminação e visualização da linha de cola por meio de fotomicrografias das amostras de madeira laminada colada. Os resultados mostraram que as vigas com 5 lâminas apresentaram valores semelhantes a madeira sólida. O aumento do número de lâminas, proporcionou menores valores para rigidez e resistência das vigas. As fotomicrografias comprovaram a qualidade da colagem e os valores satisfatórios para resistência ao cisalhamento e à delaminação, indicando a viabilidade da espécie em estudo para situações com alto teor de umidade.

ABSTRACT The glued laminated timber (glulam) is a composite material obtained from the bonding of wood laminae arranged with parallel fibers put together. The purpose of this paper was to evaluate the influence of the number of laminae on the mechanical behavior of glulam of Toona ciliata produced with vegetable-based polyurethane adhesive. The glulam beams were produced with lamellae in the dimensions of 6.0 x 1.5 x 120.0 cm, with 3 beams being made per treatment, which were structurally composed by 5, 7 and 9 laminae. The polyurethane adhesive based on castor oil was used, applying a grammage of 350 g m-². For the technological characterization of the wood the moisture in the dry base, bulk density, chemical characterization, compressive strength parallel to the fibers, shear and modulus of elasticity (MOE) and rupture (MOR) in the static bending test. While the properties of modulus of elasticity (MOE), modulus of rupture (MOR), shear strength, delamination and visualization of the glue line through photomicrographs of the laminated wood samples were determined for glulam beams. The results showed that the beams with 5 laminae presented values similar to solid wood. The increase in the number of laminae provided lower values for stiffness and strength of the beams. The photomicrographs showed the quality of the bonding and the satisfactory values for shear strength and delamination, indicating the viability of the species under study for situations with high moisture content.

RESUMO Nesta pesquisa, objetivou-se avaliar o potencial da madeira de Eucalyptus grandis e partículas de borracha de pneu na produção de painéis cimento-madeira. Foram utilizadas madeiras de Eucalyptus grandis com 8 anos de idade, provenientes da Companhia Mineira de Metais, localizada no município de Paracatu -MG. Para a formação dos painéis foi utilizado cimento Portland CPV-ARI/Plus de alta resistência inicial como aglutinante mineral e cloreto de cálcio (CaCl2) como acelerador de cura do cimento. Os painéis foram produzidos com os seguintes parâmetros: dimensões de 48,0 x 48,0 x 1,5 cm, densidade nominal de 1,2 g/cm3, relação madeira:cimento (1:2,5) e relação água:cimento (1:1,5). Os painéis foram prensados com pressão específica de 4 MPa, a temperatura ambiente, tempo de prensagem/grampeamento de 24 horas e tempo de maturação de 28 dias. A análise dos resultados obtidos, em relação aos requisitos mínimos de painéis convencionais produzidos pelo processo Bison, permite afirmar que: (1) para as propriedades físicas de densidade aparente, absorção de água e inchamento em espessura todos os tratamentos atenderam as especificações; (2) para as propriedades mecânicas de ligação interna e módulo de ruptura no ensaio de flexão estática, todos os tratamentos atenderam as especificações; (3) para compressão e módulo de elasticidade no ensaio de flexão estática, nenhum dos tratamentos apresentaram valores compatíveis com o processo bison.

ABSTRACT The objective of this research was to evaluate the potential of Eucalyptus grandis wood and rubber tire particles in the production of cement-wood panels. Eucalyptus grandis wood, 8 years old, was obtained from Companhia Mineira de Metais, located in the city of Paracatu -MG. For the formation of the panels, high initial strength CPV-ARI/Plus Portland cement was used as mineral binder and calcium chloride (CaCl2) as a cement cure accelerator. The panels were produced with the following parameters: dimensions of 48,0 x 48,0 x 1,5 cm, nominal density of 1,2 g / cm3, relation wood: cement (1:2.5) and water: cement ratio (1:1.5). The panels were pressed at a specific pressure of 4 MPa, at room temperature, 24 hour pressing/stapling time, and 28 day maturation time. The analysis of the results obtained, in relation to the minimum requirements of conventional panels produced by the Bison process, allows to affirm that: (1) for the physical properties of apparent density, water absorption and swelling in thickness all the treatments met the specifications; (2) for the mechanical properties of internal bonding and modulus of rupture in the static bending test, all treatments met the specifications; (3) for compression and modulus of elasticity in the static bending test, none of the treatments presented values compatible with the bison process.

RESUMO A indústria de painéis de madeira vem em constante crescimento, sendo necessária a inovação em tecnologias e matéria-prima para melhorar a qualidade do produto final. Considerando a escassez e pressão na diminuição da dependência por madeira, existe um interesse em outros materiais renováveis, como os resíduos agrícolas. Entre esses resíduos, o pergaminho de café merece destaque. Uma alternativa para utilização do pergaminho de café poderia ser na produção de particulados, em associação com partículas de madeira. O objetivo deste trabalho foi avaliar a viabilidade de utilização do pergaminho de café para produção de aglomerados. As porcentagens de resíduo utilizadas foram: 0, 10, 20, 30, 40 e 50% em associação com madeira de eucalipto. Os painéis foram produzidos com 8% de uréia-formaldeído (base massa seca de partículas). O ciclo de prensagem consistiu de: pré-prensagem de 0,5 MPa por 10 minutos, seguido por prensagem de 4,0 MPa e temperatura de 160° C por 15 minutos. A razão de compactação dos painéis produzidos com maiores quantidades de pergaminho melhorou as propriedades físicas. As propriedades de absorção de água (2 e 24 h) e inchamento em espessura (2 h) diminuíram com o aumento da porcentagem de pergaminho de café. O inchamento em espessura (24 h) não apresentou diferenças significativas com o aumento de resíduo de café. O Módulo de Elasticidade dos painéis variou de 646,49 ± 112,65 até 402,03 ± 66,24 MPa, enquanto o Módulo de Ruptura variou de 8,18 ± 1,39 até 4,45 ± 0,75 MPa. Os resultados mostraram que até 10% de pergaminho de café poderia ser adicionados para a produção de painéis aglomerados.

ABSTRACT 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.

O trabalho teve como objetivo avaliar o potencial de clones de Eucalyptus urophylla para produção de painéis aglomerados homogêneos de baixa densidade. Foram avaliados seis clones de Eucalyptus urophylla com 94 meses de idade, plantados no municipio de Paracatu-MG, sendo utilizada como parâmetro de comparação a madeira de Pinus oocarpa. Para cada clone de Eucalyptus urophylla e também para o Pinus oocarpa foram produzidos seis painéis com o adesivo uréia-formaldeido no teor de 6%, densidade nominal de 0,60 g/cm³, pressão especifica de 40kgf/cm², temperatura de 160ºC e tempo de 8 minutos. Os clones de Eucalyptus urophylla apresentaram potencial para produção de painéis aglomerados convencionais de baixa densidade. Os clones 62 e 28 obtiveram os melhores resultados em todas as propriedades fisico-mecânicas avaliadas, apresentando propriedades iguais ou superiores as obtidas para os painéis produzidos com a madeira de Pinus oocarpa. Com relação à norma de comercialização CS 236/1966 apenas o clone 28 atendeu a todos os requisitos. Nenhum dos clones avaliados atendeu a norma EN 312/2003.

The study aimed to evaluate the potential of Eucalyptus urophylla clones to produce homogeneous particleboard of low-density. Six clones of Eucalyptus urophylla were evaluated, at 94 months of age and planted in Paracatu-MG. Pinus oocarpa wood was used as a reference. For each Eucalyptus urophylla clone and also for Pinus oocarpa, six panels were produced with urea-formaldehyde adhesive in the concentration of 6%, nominal density of 0.60 g/cm³, specific pressure of 40kgf/cm², temperature of 160ºC and a time of 8 minutes. Eucalyptus urophylla clones presented potential for production of conventional particleboard of low density. Clones 62 and 28 showed the best results for all physical and mechanical properties evaluated, presenting properties equal or superior to those obtained for the panels produced with Pinus oocarpa wood. In relation to CS 236/1966 standard, only the clone 28 met all the requirements. None of the clones meets EN 312/2003 standard.