Abstract The objective of this research was to develop a more sustainable composite and still keep its characteristics. Fibers treated with NaOH at 5% w/w for 2 hours were incorporated into natural rubber in different proportions (0 phr, 24 phr, 36 phr, 48 phr and 60 phr). The mechanical properties of the composites suffered changes, increasing the hardness, young’s modulus and decreasing its tensile strength. All the physical properties were not statistically different. The coloration became less dark in the WF60/CB0 treatment, and the electrical properties presented better resistivity with the increase in the concentration of fibers in the composite. This presents a possibility of using WF for the production of wood-rubber composites for the production of rubber artifacts which do not require high rolling resistance. Based on the results from this research, we recommended the WF24/CB36 mix to produce antistatic floors.

Abstract Juvenile wood (JW) can influence the performance of structural boards since it presents lower physical and mechanical properties. This study aimed evaluate the influence of JW proportion on density and modulus of elasticity (MOE) on boards for structural use. Pinus taeda logs 30 years old, had growth rings manually counted (on the pith to bark direction), and the first six rings were painted with color red (0-6), followed by blue (6.1-12), orange (12.1-18), green (18.1-24), and yellow (over 24.1), successively, and cut into boards. The proportion of each color was obtained by analysis of the transversal areas of boards with software. MOE was obtained by a nondestructive test. Multiple linear regression models were applied with 5% of significance. The estimated MOE indicates that boards with at least 57% of orange and green colors (between 12.1 – 24 years old) can achieve the minimum MOE value for using as structural as well as boards without red color but with the presence of green and yellow can have MOE bigger than 7000 MPa. The study indicates a behavior tendency about which proportion and mixed colors can affect the MOE of the board to be classified as structural.

ABSTRACT The aim of this study was to evaluate the effect of the alkalization with different concentrations and time combination in the modification of lignin, hemicellulose and cellulose in pine fibers and determine the best combination aiming the incorporation in plant-based composites. The alkalization process was conducted with 5 concentrations (5, 10, 15, 20, and 30%) and 2 exposure times (2 and 24 hours). Chemical analysis was performed, and cellulose crystallinity, thermal stability, and surface modification were analyzed for the treated fibers. The results showed that there was a reduction in crystallinity with cellulose I – II transformation. Thereafter, the thermal stability and surface characteristics were increased with the increase of the NaOH concentration. Although all treatments altered the fiber properties, the condition that resulted in technical gain was the condition with 5% concentration and 2 hours of alkalization. Thus, we can conclude that this condition changes the macromolecular structure of the wood fibers, change the surface and the treat fiber could be used as filler to plant-base composite.

Abstract: The objective of this study was to evaluate the density, chemical properties and bonding quality of two lesser-used Mozambican wood species known as messassas (Brachystegia spiciformis and Julbernardia globiflora) aiming at edge-glued panel production. The bonding was performed using structural adhesive polyvinyl acetate D4, semi-structural adhesive emulsion polymer isocyanate and non-structural polyvinyl acetate D3 applied at 120·m-2 and 180·m-2 weights. Density, chemistry, edge shear bonding, wood failure percentage and the finger-joint tests were performed in accordance with standards. The results showed that both species have medium density, high extractives and lignin contents typical of tropical wood. The emulsion polymer isocyanate adhesive was approved with better performance compared to polyvinyl acetate D3 and D4 adhesives. It can also be affirmed that Brachystegia spiciformis and Julbernardia globiflora have similar bonding behaviour and the potential for producing edge glued panel panels, especially for indoor use.

Abstract: The objective of this research was to evaluate the physical-mechanical properties of wood-cement boards produced with waste particles of Pinus spp. and sufficient levels of pozzolans to assimilate all Ca(OH)2 produced during the hydration reactions of Portland cement. The pozzolans used were: silica fume, metakaolin, rice husk ash, and calcined ceramic waste. The values of the pozzolans were determined based on the theoretical determination of the Ca(OH)2 content produced by the hydration reactions of Portland cement. The pozzolanic activity index was determined by the modified Chapelle test. The boards were produced through cold compression, and the test specimens were produced and tested for physical and mechanical properties at 28/91 days of curing. The minimum values employed in the Bison® commercial process were used as a reference for the physical-mechanical characterization. The boards produced presented good physical-mechanical properties even with high levels of replacement of cement by pozzolans. These properties were similar to the ones presented by the reference boards, despite the significant reduction in the specific mass of the prototype boards, which demonstrates the technological possibility of the use of these materials in the production of wood-cement boards.

ABSTRACT This research aimed at evaluating the quality of bonded joints of Eucalyptus wood by using different faces and adhesives to produce EGP (Edge Glued Panels). Glue line shear specimens were obtained from bonded joints glued with PVAc (Polyvinyl Acetate) and EPI (Emulsion Polymer Isocyanate) adhesives, using pieces oriented with tangential, radial and intermediary faces, as well as the combination between them. The specimens were submitted to two pretreatments in order to simulate the use of joints in dry and wet environments. For shear tests, 12 treatments were obtained. The results indicated that the use of tangential x tangential and tangential x intermediary bonding faces and EPI adhesive presented better glue line shear strength for EGP in dry and wet pretreatments, respectively. The joints bonded in the radial x radial direction presented statistically inferior values when compared to the other treatments.

Resumo O objetivo deste trabalho foi avaliar o potencial das madeiras de Eucalyptus benthamii, Eucalyptus dunnii, Eucalyptus grandis, Eucalyptus saligna e Eucalyptus urophylla, para produção de painéis colados lateralmente (EGP) e madeira laminada colada (MLC). As propriedades físicas e químicas das madeiras foram determinadas com base nas normas COPANT 461/459:1972 e TAPPI 204/252:2002. Foram confeccionadas juntas coladas com adesivo acetato de polivinila (PVA), com gramaturas de 150 g m-2 e 200 g m-2, e resorcina-formaldeído (RF), com 200 g m-2 e 300 g m-2. A qualidade de colagem foi avaliada por meio de ensaios de cisalhamento, com base na norma EN 13354:2008. Todas as espécies apresentaram densidade básica de média a baixa e anisotropia de contração de média a alta. O teor de extrativos totais e pH estão dentro da faixa referenciada na literatura. As avaliações dos resultados com base nos requisitos da norma EN 15353:2008 para 5º percentil inferior indicaram que as espécies E. benthamii, E. dunnii, E. grandis e E. saligna, apresentam potencial para produção de painéis EGP com adesivo PVA, para o uso interno, e externo com cobertura. Para a colagem com adesivo RF, o E. dunni apresentou melhores resultados, sendo indicativo do seu bom potencial para a produção de madeira laminada colada, visando aplicações estruturais em ambientes interno úmido e externo. Para os dois tipos de adesivos o aumento na gramatura não afetou os resultados de cisalhamento das juntas coladas.

Abstract The objective of this work was to evaluate the potential of wood of Eucalyptus benthamii, Eucalyptus dunnii, Eucalyptus grandis, Eucalyptus saligna and Eucalyptus urophylla for the production of edge glued panels (EGP) and glued laminated timber (Glulam). Physical and chemical properties of the wood were determined based on the COPAN 461/459:1972 and TAPPI 204/252:2002 standards. Glued joints were manufactured in resin weights of 150 g m-2 and 200 g m-2 for polyvinyl acetate (PVA) and 200 g m-2 and 300 g m-2 for resorcinol-formaldehyde (RF). Bonding quality was evaluated by shear tests based on EN 13354-2008 standard document. All species presented medium to low basic density and medium to high contraction anisotropy. The total extractives content and pH are within the range referenced in the literature. The evaluation of the results based on the requirements of standard document EN 15353-2008 for the 5th lower percentile indicated that the E. benthamii, E. dunnii, E. grandis and E. saligna species showed high potential for the production of EGP with PVA adhesive, for indoor and outdoor use with coverage. For RF adhesive bonding, E. dunni showed better results, being indicative of its good potential for the production of glued laminated timber - GLULAM, for structural applications in the external environment. For both types of adhesives, the increase in weight did not affect the shear results of bonded joints.

Abstract This study evaluated the quality of the particleboard produced with particles generated from mobile discharges with mixture of equal parts of industrial particles of Pinus. The material was collected and processed in the form of chips by a company specialized in waste recycling. The experimental plan consisted in producing panels with nominal density 0.55, 0.70 and 0.85 g/cm3, and urea-formaldehyde resin of 8, 10 and 12%. The increased density and resin content contributed to improve the physical and mechanical properties of the panels. The panels produced with nominal density of 0.70 and 0.85 g/cm3, and 10% resin content, showed better feasibility of using mobile discharges particles in a proportion of 50% mixture with particles of Pinus industrial production of particleboards.

Resumo Este trabalho teve como objetivo avaliar o potencial de uso de três diferentes aditivos químicos (CaCl2, MgCl2 e cal hidratada) na produção de compósitos madeira-cimento manufaturados com a mistura de partículas de madeira de costaneira de piãozinho (Eschweilera coriaceae (DC.) Mart) e matá-mata-branco (Eschweilera odora (poepp.) Miers) e cimento Portland tipo CP II-Z, na razão 1:2,75, pelo método de adensamento por vibrocompactação. Teste de compatibilidade entre a madeira e cimento mostrou que essas espécies são aptas para a produção de compósitos quando pré-tratadas com o uso de aditivos químicos na mistura. Com base nos resultados, pode-se concluir que: (I) As espécies do gênero Eschweilera estudadas são aptas para produção de compósitos madeira-cimento, sendo que compósitos produzidos com a madeira de piãozinho (Eschweilera coriaceae) obtiveram melhores resultados; (II) A adição de CaCl2 teve efeito positivo nas propriedades mecânicas dos compósitos de Eschweilera coriaceae; e (III) Não é recomendável o uso de cal hidratada como aditivo químico quando o método utilizado é o de vibrocompactação.

Abstract The aim of this work was to evaluate the potential use of three different chemical additives (CaCl2, MgCl2 and hydrated lime) in the production of wood-cement composites made with particles from the slab wood of piãozinho (Eschweilera coriaceae (DC.) Mart), matá-mata branco (Eschweilera odora (poepp.) Miers) and Portland cement CP II-Z, with a wood:cement ratio of 1:2,75, by the vibro-compaction densification method. The compatibility test between wood and cement indicated that both species were suitable for the composites production when pre-treated and mixed with chemical additives. Main results: (I) The two species of the Eschweilera genus are suitable for wood-cement composite productions; Composites produced with piãozinho (Eschweilera coriaceae) particles presented better results (II) The use of CaCl2 had a positive effect on the mechanical properties of composites with Eschweilera coriaceae wood; and (III) The use of hydrated lime as chemical additives is not recommended when the method of densification by vibro-compaction is applied.

RESUMO Compósito madeira-cimento é um potencial material de construção para regiões tropicais, devido a suas propriedades físico-mecânicas e resistência ao ataque de fungos e podridão. Contudo, é importante testar métodos alternativos de produção e madeiras que sejam mais simples e baratos do que os tradicionalmente usados, para que se alcance uma maior demanda para esse produto. O objetivo deste estudo foi avaliar o uso de madeira de quatro espécies amazônicas (Eschweilera coriaceae, Swartzia recurva, Manilkara amazonica e Pouteria guianensis) na produção de compósitos de madeira-cimento (WCC) pelo processo de compactação vibro-dinâmica, um método alternativo que dispensa o uso de prensas hidráulicas. O grau de inibição à pega do cimento causado pela presença da madeira foi medido pelo fator CA e indicou que todas as quatro espécies foram compatíveis com o cimento Portland (CP II-Z). Compósitos com massa específica superior a 1.100 kg m-3 (produzidas com partículas de E. coriaceae e S. recurva) apresentaram valores de compressão axial acima de 10 MPa, requisito mínimo para classificar como blocos de concreto reforçados leves de uso estrutural.

ABSTRACT Wood-cement composite (WCC) is a potential construction material for tropical regions, due to its physico-mechanical properties and resistance to decay and fungi attack. However it is important to test alternative production methods and wood materials that are easier and cheaper than those traditionally used, in order to create a higher demand for this product. The aim of this work was to evaluate the use of wood from four Amazonian species (Eschweilera coriaceae, Swartzia recurva, Manilkara amazonica and Pouteria guianensis) in the production of wood-cement composites through a vibro-dynamic compression process, an alternative method to the use of a hydraulic press. The inhibition degree caused by the wood to the cement cure, measured by the factor CA, indicated that all species were compatible with Portland cement (CP II-Z). WCC with densities higher than 1,100 kg m-3 (produced with E. coriaceae and S. recurva particles) showed compressive strength values higher than 10 MPa, which fulfills the minimum requirement for lightweitgh reinforced concrete blocks for structural use.

RESUMO Esse trabalho teve como objetivo avaliar o potencial de uso da madeira de quatro espécies tropicais da Amazônia na produção de compósitos madeira-cimento pelo método de adensamento por vibro compactação. As partículas de madeira foram produzidas a partir de costaneiras das espécies Murici (Byrsonima crispa), Ingá vermelho (Inga paraensis), Ingá (Inga alba) e Mata-Matá (Eschweilera odora). Todas as espécies foram consideradas aptas para a produção de compósitos de acordo com o teste Fator CA . Foram testadas as propriedades físicas (densidade, absorção de água e inchamento em espessura) e mecânicas (ligação interna, flexão estática e resistência à compressão) dos compósitos. A densidade da madeira e o tamanho de suas partículas influenciaram a densidade final do compósito e suas propriedades de absorção de água e o módulo de elasticidade. A área superficial da partícula também afetou negativamente a resistência à compressão do material. Tanto o método quanto a madeira apresentaram potencial para fabricação de compósitos com possíveis aplicações como materiais de preenchimento na construção civil

ABSTRACT The aim of this work was evaluate the potential use of timbers from four tropical Amazonian species for production of wood-cement composites by vibro-compaction densification method. Wood particles were made from slab wood of Murici (Byrsonima crispa), Red Inga (Inga paraensis), Inga (Inga alba) e Mata-Mata (Eschweilera odora). All species were considered suitable for composites production according to the CA Factor test. Composites physical (density, water absorption and thickness swelling) and mechanical (internal bond, static bending and compressive strength) properties were evaluated. Wood density and particle size influenced the composites final density and their water absorption and modulus of elasticity properties. The particle surface area also affected negatively the material's axial compressive strength. Method and wood showed potential for production of composites with possible application as filling materials in civil construction.

RESUMO O objetivo desta pesquisa foi avaliar a redução da alcalinidade de compósitos cimento-madeira, produzido com cimento Portland e partículas residuais de Pinus spp., em função da substituição gradual do cimento Portland pelas pozolanas sílica ativa (SA) metacaulim (MK), cinza volante (CV), escória de alto-forno (EAF), cinza de casca de arroz (CCA) e resíduo de cerâmica calcinada (RCC). Para tanto, foram produzidos corpos de prova cilíndricos, com diâmetro de 5 cm, com compósitos com 100% de cimento Portland e partículas residuais de Pinus spp., adotados como referência e, com substituições parciais do cimento por 0%, 5%, 10%, 15% e 20% de SA, 0%, 10%, 20%, 30% e 40% de MK, CV, CCA e RCC e 0%, 30%, 40%, 50% e 60% de EAF. O resíduo de Pinus spp. inicialmente passou por pré-tratamento tipo extração em água fria por um período de 24 horas para melhorar a compatibilidade com a matriz cimentícia. Na produção dos compósitos foi utilizado um aditivo superplastificante de 1ª geração, base de lignosulfonatos, naftalenos e melaninas em teores que variaram entre 0% a 7,8% do teor de cimento e das pozolanas utilizadas e cloreto de cálcio bi-hidratado (CaCl2.2H2O) como aditivo acelerador de pega, em teores que variaram entre 0% a 4,5%, calculados em massa em relação ao teor de cimento dos compósitos. Os compósitos ficaram em cura imersa por um período de 91 dias e após esse período foram moídos e adicionados a água deionizada, sendo o pH determinado através da solução de equilíbrio. Em relação ao compósito de Referência, que apresentou pH = 12,67, foram verificadas quedas significativas da alcalinidade dos compósitos estudados, em função da utilização das substituições parciais do cimento Portland, de 10,02% (20% de SA, com 4,5% de CaCl2.2H2O e 4,4% de SP), 12,55% (40% de MK, com 4,5% de CaCl2.2H2O e 7,8% de SP), 5,13% (40% de CV com 4,5% de CaCl2.2H2O), 3,87% (60% de EAF com 4,5% de CaCl2.2H2O), 15,15% (40% de CCA, com 4,5% de CaCl2.2H2O e 4,2% de SP) e 8,29% (40% de RCC, com 4,5% de CaCl2.2H2O e 2,6% de SP).

ABSTRACT The objective of this research was to evaluate the alkalinity reduction of the wood-cement composites produced with Portland cement and residual particles of Pinus spp., as a function of the gradual replacement of the Portland cement by the pozzolans silica fume (SA) metakaolin (MK), fly ash (CV), blast slag furnace (EAF), rice husk ash (CCA) and calcined ceramic residue (RCC). For this, 5 cm diameter cylindrical specimens were produced with composites wiyh 100% Portland cement and residual Pinus spp. particles, adopted as reference and with partial cement replacements by 0%, 5%, 10%, 15% and 20% of SA, 0%, 10%, 20%, 30% e 40% de MK, CV, CCA e RCC e 0%, 30%, 40%, 50% e 60% de EAF. The Pinus spp. residue initially underwent pre-treatment type extraction in cold water for a period of 24 hours to improve compatibility with the cementitious matrix. In the production of the composites a superplasticizer additive of 1st generation was used, based on lignosulphonates, naphthalenes and melanins in contents ranging from 0.20% to 7.8% of the cement and pozzolan and content and hydrated calcium chloride (CaCl2.2H2O) was used with accelerator additive in amounts ranging from 0% to 4.5% calculated in mass in relation to the cement content of the composites. The composites were immersed for a period of 91 days and after that period were grounded and added to the deionized water, and the pH was determined through the equilibrium solution. Significant reductions in the pH of the composites were determined in relation to the pH value of the reference composite (12.67) of the order of 10.02% (20% de SA, with 4.5% of CaCl2.2H2O and 4.4% of SP), 12.55% (40% de MK, with 4.5% of CaCl2.2H2O and 7.8% of SP), 5.13% (40% of CVwith 4.5% of CaCl2.2H2O), 3.87% (60% of EAF with 4.5% of CaCl2.2H2O), 15.15% (40% of CCA, with 4.5% of CaCl2.2H2O and 4.2%of SP) and 8.29% (40% of RCC, with 4.5% of CaCl2.2H2O and 2.6% of SP).

RESUMO O objetivo do trabalho foi avaliar a viabilidade de uso da resina lignina-fenol-formaldeído na produção de painel aglomerado estrutural de Mimosa scabrella Benth (bracatinga). Os painéis foram produzidos com massa específica nominal de 750 kg.m-3 e 950 kg.m-3, 10 e 12% de resina fenol-formaldeído e lignina-fenol-formaldeído, e 10 e 12 minutos de prensagem. A qualidade dos painéis experimentais foi avaliada por meio de seguintes ensaios físico-mecânicos: massa específica, razão de compactação, absorção de água e inchamento em espessura 2 e 24 horas, tração perpendicular, flexão estática e arrancamento de parafuso. Foram constatadas interações positivas da massa específica, teor de resina e tempo de prensagem nas propriedades dos painéis produzidos. A avaliação dos resultados das propriedades com base nos requisitos da norma EN 312:2003 (tipo P5), indicaram a viabilidade de uso da resina lignina-fenol-formaldeído na produção de painel aglomerado de Mimosa scabrellla para aplicações estruturais.

ABSTRACT The objective of this work was to evaluate the feasibility of using lignin-phenol-formaldehyde resin in the production of Mimosa scabrella Benth (bracatinga) structural particleboard. The boards were produced with nominal specific mass of 0.75 and 0.95 g/cm3, 10% and 12% of phenol-formaldehyde and lignin-phenol-formaldehyde resins, with 10 and 12 min of pressing time. The boards quality was evaluated by means of the following physical-mechanical tests: specific mass, compression ratio, water absorption and thickness swelling after 2 and 24 hours soaking, perpendicular traction, static bending and screw pulling. Positive interactions of specific mass, resin content and pressing time were observed in the properties of the boards produced. The evaluation of the properties results based on the requirements of EN 312 (type P5) standard indicated the feasibility of using lignin-phenol-formaldehyde resin in the production of particleboard of Mimosa scabrellla for structural applications.

ABSTRACT The objective of this work was to study the fiber length variation, retractability and basic density, in the core-bark direction and along the heig of the red tauari wood (Cariniana micrantha Ducke). The stem was evaluated in the discs, from core to bark, corresponding to 0%, 25%, 50%, 75% and 100%. At the commercial height of the tree the evaluation was carried out in the Base, DBH, 50%, 75% and 100%. Three trees were collected and 5 discs of 12 cm of thickness were taken from each tree the heights: Base, DAP, 50%, 75% and 100%. Results indicated that the fiber length increases in the radial direction core-bark and decreases in the longitudinal direction, from base to top. The analysis of the basic density varied in the core-bark direction, with tendency to increase from the position of 50% (heartwood), then decreasing in the sapwood region. Total volumetric and linear contractions decreased in the core-bark direction.

Abstract: The objective of this study was to evaluate the feasibility of construction and demolition (C&D) waste wood to produce of particleboard. The raw material was obtained from a waste recycling company and it was divided into four types of materials: MDF (medium density fiberboard), MDP (medium density particleboard), plywood and timber. After reduction of these wood product residues to particles, particleboards were produced, in the UFPR Laboratory, with urea-formaldehyde resin and a target density of 0,75 g / cm³ and their physical and mechanical properties were determined. Particleboards made from industrial Pinus spp. particles were also produced as control samples. C&D wood waste showed potential for use as raw material for particleboard. The properties of particleboard made of recycled timber, MDP, plywood and the mixture of the four sources of material indicated that particleboard industries could use these waste resources for the production of the inner layer of MDP products.