Orientador: Sérgio Augusto Mello da Silva / Resumo: O desenvolvimento de estudos para produção de derivados de madeira tem representado uma real alternativa para contribuir as políticas de sustentabilidade, principalmente de espécies arbóreas nativas. Nesse contexto, o reaproveitamento de resíduos lignocelulósicos tem contribuído como uma alternativa para a produção industrial de painéis de madeira. Dentro desse contexto este trabalho se constitui do estudo para produção e avaliação de painéis aglomerados, empregando-se partículas de bagaço de cana-de-açúcar (Saccharum officinarum) e partículas de madeira de pinus (Pinus taeda; Pinus elliottii) e utilizando-se dois tipos de aglutinantes, o Poliuretano derivado do óleo de mamona (PU-M) e a Resina Ureia-formaldeído (UF). Para produção dos painéis foram propostos diferentes tratamentos com variações entre as proporções de massas das partículas, densidade nominal dos painéis de 0,80 g/cm3 e pressão de prensagem de 50 kgf/cm2 durante 10 min. As misturas de partículas foram utilizadas com 10% de umidade para o adesivo PU-M e 3% de umidade para a resina UF ambos com um conteúdo de 10% em relação à massa seca das partículas. Para prensagem dos painéis com PU-M empregou-se 100 ºC e para os painéis com UF 130 ºC. Os painéis foram submetidos a ensaios para avaliação das propriedades físicas (densidade, umidade e inchamento) e mecânicas (módulo de elasticidade, módulo de ruptura à flexão e tração perpendicular) de acordo com a ABNT NBR 14810-1 e 2 (2013). Os resultados obtidos evidenciara... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The development of studies for the production of wood derivatives has represented a real alternative to improve sustainability policies, mainly of native tree species. In this context, the reuse of lignocellulosic waste has contributed as an alternative to the industrial production of wood panels. This way, this work aims to produce and evaluate chipboards using particles of sugarcane bagasse (Saccharum officinarum) and particles of pine wood (Pinus taeda; Pinus elliottii) and using two types of binders, the Polyurethane derived from castor oil (PU-Castor) and Urea formaldehyde resin (UF). Different treatments were proposed for the production of boards with variations between the particle mass ratios, panels’ nominal density of 0.80 g/cm3 and pressing pressure of 50 kgf/cm2 for 10 minutes. Particle mixtures were used at 10% moisture for the PU-Castor adhesive and 3% moisture for the UF resin both with a content of 10% relative to the dry mass of the particles. For the pressing of panels with PU-Castor was used 100 °C and of panels with UF was used 130 °C. The boards were submitted to tests to evaluate the physical properties (density, moisture and swelling after 24 hours) and mechanical (modulus of elasticity, modulus of resistance to bending and perpendicular traction) according to the ABNT NBR 14810-1 and 2 (2013). The results showed that it is possible to use particles from sugarcane bagasse and pine wood for high density chipboards production. It was found that the boards... (Complete abstract click electronic access below) / Mestre

Interest in the use of mass timber in building and construction is growing worldwide, this is due to the structural integrity and reduced environmental footprint of timber-based structures. Concerns associated with the biological and environmental degradation of mass timber necessitate the development of adequate protection strategies to ensure the durability of these products. Preservative treatment is a proven technique that increases the durability and performance of wood in-service and can also be applied to large-sized timber panels such as cross-laminated timber (CLT). Therefore, this study focused on investigating the feasibility of treating prefabricated 3- and 5-layer CLT panels with Copper-azole type C (CA-C) and micronized copper azole (MCA) preservatives. Further, we studied the effects of panel layup and thickness on the preservative impregnation in CLT. Based on the experimental results, we found adequate preservative penetration and retention in the treated 3- and 5-layer CLT panels, particularly in CA-C treated panels. Also, the lengthwise layup shows better treatment results in both CA-C and MCA-treated panels. In addition to the preservative-treatment of CLT panels, this dissertation covers the development of lignin-reinforced polyurethane adhesive (PUR) for bonding glue-laminated timber (Glulam). Herein, the glulam were fabricated and bonded using lignin-reinforced PUR at different wt% (1, 2, and 3) and tested for shear strength, wood failure and delamination. The lignin-treated PUR samples showed improved adhesion properties via high shear strength and reduced delamination compared to the control specimens. Thus, the lignin-reinforced PUR adhesive shows great potential as a bio-based and environment-friendly wood adhesive for producing glulam used in structural applications.