Search

Natural resource exploration is growing, highlighting woods and joinery waste, wood industries and the like. This study presents homogeneous particleboard (PPH) roughness characterization manufactured from treated wood waste. Normative document with values of Brazilian Technical Standard Association ABNT NBR 8404 (1984), was adopted as a reference. The results show that the manufactured PPH showed roughness class N 10, with roughness values (Ra) of less than 12.5 microns.

This study aimed to evaluate the mechanical performance of laminated composite materials (fiberglass, carbon, sisal, palm fiber) in epoxy matrix as reinforcement in wood particleboards of Pinus sp. with bicomponent polyurethane resin from castor oil. Modulus of elasticity (MOE) and modulus of rupture (MOR) were investigated using a three-point bending test. Single-layered laminated plates were used to reinforce traction of specimens obtained from boards. MOE and MOR of materials developed without reinforcements exceeded limits in ABNT standards both NBR 12810-2:2002 and A208.1:199, proving therefore their feasibility. In all investigated cases, inclusion of reinforcements led to higher values for both MOE and MOR. Composites in fiberglass presented the best results. RESUMO Este trabalho objetivou avaliar o desempenho mecânico do emprego de materiais compósitos laminados (fibras de vidro; carbono; sisal; piaçava) em matriz epóxi, como reforço em painéis de partículas de madeira Pinus sp. com resina poliuretana bicomponente, derivada de óleo de mamona. Foram investigados, com o uso do ensaio de flexão estática a três pontos, o módulo de elasticidade (MOE) e o módulo de ruptura (MOR). Os compósitos laminados foram fabricados com camada única, reforçando à tração os corpos de prova obtidos dos painéis. Os resultados do MOE e do MOR dos materiais desenvolvidos sem a inclusão dos reforços superaram os limites contidos nos documentos normativos ABNT NBR 14810-2:2002 e A208.1:199, comprovando a viabilidade dos materiais elaborados. Em todos os casos investigados, a inclusão dos reforços conduziu a valores superiores, tanto para o MOE quanto para o MOR, apresentando os compósitos em fibras de vidro os melhores resultados.

Wood-based panels have been widely used around the world in various segments of timber industry. Thus, alternative raw-materials have been systematically researched in order to reduce of wood demand in particleboard production. The aim of this work was to produce and evaluate particleboards of Eucalyptus grandis and oat hulls (Avena sativa), bonded under pressure with castor oil based polyurethane resin, in the proportion of 10% relative to the dry mass of the particles. The percentages of particles used per material were: Eucalyptus grandis 100, 85, 70 e 0% and oat hulls 0, 15, 30 e 100%, respectively. Physical-mechanical performance of the panels produced was evaluated based on standards ABNT NBR 14810:2006[1] and BS EN 312:2003[2]. By analysis of variance (ANOVA), the fraction of particles of Eucalyptus grandis was significant only in the modulus of rupture (MOR) in static bending. Panels produced with 100% oat hulls presented highest value of MOR.

This paper discusses the potential use of sugarcane bagasse in two different fiber lengths (5 mm and 8 mm) of the same density as a raw material for the production of particleboards, using castor oil-based two-component polyurethane adhesive. The quality of the product that can be manufactured industrially was evaluated based on density, thickness swell (TS), absorption (WA), modulus of elasticity (MOE), modulus of rupture (MOR) in static bending and internal bond (IB), according to the Brazilian NBR 14.810:2006 standard. The results revealed a significant difference between the particleboards made with 5-mm-long fibers and those made with 8-mm-long fibers. An analysis by scanning electron microscopy (SEM) indicates that the interparticle spaces are filled with castor oil-based two-component polyurethane adhesive, contributing to improve the physicomechanical properties of the particleboards. A durability assessment based on accelerated aging tests shows that waterproofed particleboards can be used in moist environments.

No presente trabalho, considera-se o estudo do potencial de utilização de resíduos da casca de amendoim, com o intuito de agregar valor a este material, por meio da fabricação de painéis de partículas aglomeradas com resina ureia-formaldeído, prensados à temperatura de 100 ºC. A qualidade dos painéis foi avaliada com base nas prescrições do documento normativo ASTM D 1037:2006 por meio de ensaios físico-mecânicos de densidade, inchamento em espessura, absorção de água e flexão estática. Os painéis avaliados apresentaram densidade média variando de 0,69 a 0,83 g cm-3, MOR 4,37 a 5,34 MPa e MOE 590 a 700 MPa, para painéis com e sem tratamento preservativo. É possível afirmar, baseando-se no documento normativo ANSI A208.1:1993, que o material apresenta potencial para utilização em ambientes internos, como revestimento superficial de residências, construções agrícolas, setor moveleiro e decorativo. Recomenda-se a intervenção no processo de fabricação do painel, para melhorar as propriedades mecânicas e possibilitar o uso estrutural do material. In this study, the potential use of residues of peanut husks was verified, in order to add value to these materials through the manufacture of panels of particleboards. For this procedure, it was used urea-formaldehyde resin and the panels were mechanical pressed at a temperature of 100 ºC. The quality of the panels was evaluated based on the prescriptions of the normative document ASTM D 1037:2006, through physical and mechanical tests of characteristics, such as: density, swelling in thickness, water absorption and static bending. The panels evaluated showed bulk density varying between 0,69 a 0,83 g cm-3, MOR and MOE between 4,37 - 5,34 MPa and 590 - 700 MPa respectively, for panels with and without preservative treatment. It is possible to claim, based in the normative document ANSI A208.1:1993, that the material presents a potential for use in internal areas as superficial covering of residential buildings, agricultural buildings, furniture and decorative sectors. Intervention in the board production process is recommended, in order to improve the mechanical properties of the material and enable its structural use.