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ResumoEste estudo teve como objetivo avaliar a qualidade de painéis aglomerados produzidos com misturas de seis espécies de madeiras tropicais da Amazônia e Pinus taeda. As espécies estudadas foram: Eschweilera odora, Byrsonima crispa, Swartzia recurva, Eschweilera coriacea, Manilkara amazonica e Pouteria guianensis. O plano experimental consistiu em mistura de três espécies tropicais e, mistura destas na proporção de 50% com Pinus taeda. Foram produzidos painéis experimentais com densidade nominal de 0,75 g/cm 3 , utilizando a resina uréia-formaldeído na proporção de 8% de sólidos -base peso seco das partículas. Os painéis foram prensados com pressão específica de 4,0 MPa, temperatura de 160 ºC e tempo de prensagem de 8 minutos. Apesar das diferenças entre massa específica, teores de extrativos totais e pH das madeiras, além da razão de compactação dos painéis, não foram constatadas interações claras entre estas variáveis e as propriedades dos painéis aglomerados. Com base nas comparações com os requisitos normativos e resultados obtidos para a espécie referencial -Pinus taeda, pode-se afirmar que as seis espécies de madeiras tropicais estudadas apresentam potencial para produção de painéis aglomerados. Palavras-chave: Espécies tropicais; mistura de espécies; resina uréia-formaldeído. AbstractParticleboard production with mixture of six wood species of the Amazonia and Pinus taeda. This study aimed to evaluate the quality of particleboard produced from the mixture of six wood species of the Amazon and Pinus taeda taeda taeda. The Amazonia wood species studied were: Eschweilera odora, Byrsonima crispa, Swartzia recurva, Eschweilera coriacea, Manilkara amazonica and Pouteria guianensis. The experimental design consisted of a mixture of three tropical species, in a proportion of 50% and Pinus taeda. Experimental panels were produced with 0.75 g/cm³ nominal density, using urea-formaldehyde resin at 8% based on solid dry weight of the particles. The panels were pressed with the following conditions: 4.0 MPa specific pressure, 160 ºC temperature and a 8 minutes of pressing time. Despite the differences in density, extractives content and pH of the wood, besides of the board compression ratio, clear interactions between these variables and the properties of the particle boards were not found. Based on comparisons with standard requirements and results for the reference species -Pinus taeda, it can be concluded that the wood of six tropical species studied have potential for particleboard production.

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It is a well-discussed topic that Construction and Demolition Waste (CDW) can be recycled and used as aggregate in the construction sector. Generally, Brazilian construction techniques are based on hollow blocks or bricks and mortars as coating systems. This paper describes the sound insulation of a masonry wall built with hollow concrete blocks and CDW as aggregates. The measurements were performed according to the reverberant chamber method. Keeping sustainability in mind instead of applying cement mortar as coating system, Oriented Strand Boards (OSB) and Wood-Wool Cement Boards (WWCB) were used and also tested as acoustical linings. The panels were directly attached on the wall with nails in the receiving room. All types of panels increased the weighted sound reduction index ([Formula: see text]). Wood-based composites can also improve the air quality because of their hygroscopic properties. In summary, sustainable wall systems were characterized according to their sound insulation properties, presented as possible substitutes for traditional masonry walls.