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.

-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/cm 3 , 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 160°C 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.Keywords: Pinus particles; Panels pressing; urea-formaldehyde resin. UTILIZAÇÃO DE RESÍDUOS DE EXPLORAÇÃO FLORESTAL DE Pinus taeda PARA PRODUÇÃO DE PAINÉIS AGLOMERADOSRESUMO -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/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. 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

O objetivo desta pesquisa foi avaliar a influência do adesivo, das gramaturas e dos tempos de prensagem nas propriedades mecânicas de vigas laminadas coladas, confeccionadas com madeira de teca (Tectona grandis). As vigas foram produzidas com cinco lamelas, sendo duas da classe de módulo de elasticidade dinâmico, classe 1-MOEd C1 nas faces, e três da classe 2-MOEd C2 no miolo. Para a colagem, utilizou-se o adesivo à base de resorcina-fenolformaldeído (RFF), com gramaturas de 350 e 450 g.m-2 , e tempos de prensagem de 5 e 8 horas. Para o adesivo à base de emulsão polimérica de isocianato (EPI), a colagem foi realizada com gramaturas de 180 e 220 g.m-2 , e tempos de prensagem de 3 e 4 horas. Os resultados das propriedades mecânicas das vigas indicaram que não houve uma relação bem definida dos efeitos das variáveis de estudo nas propriedades de flexão estática. As vigas coladas com o adesivo RFF tiveram maior resistência da linha de cola em comparação às vigas coladas com o adesivo EPI.

This study aimed to evaluate the influence of the wood grading by the method of stress waves in the mechanical properties of glued laminated beams (glulam) made of Tectona grandis. A total of 87 battens with dimensions of 25 x 75 x 3.000 mm were obtained from the 5 trees and 3 logs per tree, in the axial direction (base, middle and top) and radial (pith -bark). After drying, the battens were planed to the final dimensions of 20 x 60 x 2200 mm, and then subjected to grading by application of stress waves. Were defined three classes of dynamic modulus of elasticity (DMOE) and the beams were composed with five pre-classified battens. The beams were bonded with resorcinol-phenol-formaldehyde resin, with a weight of 350 g / m² (double surface), specific pressure of 1.0 MPa and pressing time of 8 hours. The grading process of the battens using the stress wave method showed to be efficient for the composition of beams. The results of static bend and glue line shear strength tests indicated the technical feasibility of using wood of Tectona grandis for the production of glued laminated beams.

This research proposes a wall panel component molded from a wood of bracatinga (Mimosa Scabrella) and a lignin-phenol-formaldehyde adhesive. The development of a product with a simple and ecological construction technology was adopted as the approach, using low-cost wood particles. A composite made of bracatinga wood particles and alternative residual lignin (lignin-phenol-formaldehyde) adhesive was developed and characterized. The designed wall panel component was prototyped in full scale to evaluate the molding process and the final quality of the product. Preliminary results obtained with the pilot experiment demonstrated that the composite had properties and values that met the requirements of the standards EN 312:2010 and NBR 14810-2:2013, for structural boards for use in humid conditions (type P5). To prove the ecological aspect of the product, CO2 emissions resulting from its manufacture and the amounts of carbon of non-fossil origin and fixed by it (expressed as CO2 uptake) were calculated. The final balance proved to be favorable.