Abstract The aimed to evaluate the properties of MDP and HDP panels, produced with pure Populus deltoides or in a mixture with Pinus taeda, together with urea-formaldehyde resin. The density and chemical properties of this wood with 8 and 12 years of age were determined, which were used for the production of panels with nominal density of 0.65 and 0.90 g.cm-3. Water absorption and thickness swelling tests were performed after 2 and 24 hours of immersion, as well as static bending and perpendicular tensile. Populus deltoides wood was classified as low-density in both ages and presented chemical properties similar to Pinus taeda. Mechanical properties obtained for the panels produced reached the minimum requirements values established by the standards NBR 14810-2 and ANSI A208.1, demonstrating the potential use of wood species for the production of MDP and HDP panels, at both ages studied and used pure or mixed with Pinus taeda wood.

RESUMO Esta pesquisa teve como objetivo avaliar a qualidade de painéis aglomerados produzidos com resíduos de exploração florestal de Pinus taeda. O material na forma de galhos e ponteiras e de tocos e raízes, foram obtidas de um plantio florestal localizado no Município de Mafra - SC. Todo o material foi transformado em cavacos para biomassa e transportados até o local de estudos. As partículas industriais de Pinus foram utilizadas como testemunha e em mistura com os resíduos em diferentes proporções. O plano experimental consistiu na produção de painéis com 100% de cada tipo de material e em mistura destes com proporções de 75/25%, 50/50% e 25/75% com partículas industriais de pinus, além da mistura em partes iguais dos três tipos de materiais. Foram produzidos painéis experimentais com densidade nominal de 0,75 g/cm3, 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. Os resultados dos ensaios de tração perpendicular atenderam aos requisitos da norma E 312, sendo indicativo de que houve uma colagem adequada destas partículas provenientes de resíduos de exploração florestal. Avaliações gerais dos resultados das propriedades físicas e mecânicas dos painéis experimentais indicam a possibilidade de uso de partículas obtidas a partir de galhos e ponteiras e de tocos e raízes em mistura com as partículas industriais de pinus na proporção de até 50% para produção de painéis aglomerados.

ABSTRACT This study aimed to evaluate the quality of particleboards manufactured with forest exploitation waste from Pinus taeda. The material in the form of branches, tree tops, stumps and roots, was obtained from a forest plantation located in the Municipality of Mafra -SC. All the material was processed into wood chips for biomass and transported to the place of studies. The Pinus industrial particles were used as control and mixed with the waste in different proportions. The experimental plan consisted of the panels manufacture with 100% of each type of material and mixture of these com proportions of 75/25%, 50/50% and 25/75% with Pinus industrial particles, in addition to the mixture in equal parts, of the three types of materials. Experimental panels were manufactured with nominal density of 0.75 g/cm3, using the urea-formaldehyde resin, in the proportion of 8% of solids -dry weight basis of the particles. The panels were pressed with specific pressure of 4.0 MPa, temperature of 160ºC and pressing time of 8 minutes. The results of the internal bond tests met the requirements of the standard EN 312, is indicative that there has been a proper bonding of these particles originating forest exploitation wastes. General evaluations of the physical and mechanical properties results of the experimental panels indicate the possibility of use of particles obtained from branches, tree tops, stumps and roots, mixed com the industrial Pinus particles, in proportion of, up to, 50%, for particleboard manufacture.