Influência da impregnação contra demanda biológica em propriedades físico-mecânicas de madeiras tropicais brasileiras

Abstract

AGRADECIMENTOSPrimeiramente agradeço a Deus por tudo. À memória de minha mãe Sandra, por todo amor. À minha irmã Amanda e ao meu pai Valmir, pelo apoio e carinho.Ao meu noivo Gabriel, por todo apoio e incentivo, proporcionados sempre com muito amor, carinho e companheirismo.Aos meus sogros, Claudete e José Eduardo, pela ajuda e carinho.Alves Dias, e aos técnicos que me auxiliaram na elaboração deste trabalho.Ao Departamento de Engenharia de Materiais, pela oportunidade da realização do curso de mestrado. À Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) -Código de Financiamento 001, pela concessão da bolsa de mestrado e por todo auxílio financeiro prestado. Agradeço a todos que contribuíram para a realização deste trabalho. ABSTRACT ALMEIDA, A. S. Influence of impregnation against biological demand on physicalmechanical properties of Brazilian tropical woods. 2019. 86 p. Master's Dissertation (Master in Science and Engineering of Materials) -School of Engineering of São Carlos, University of São Paulo, São Carlos, 2019. The chemical preservation aims to protect the wood against any deteriorating actions, be they consequences of physical-chemical phenomena, such as weathering, or biological phenomena, such as xylophagous organisms. In Brazil, the most used preservatives in the preservation plants are Chromated Copper Arsenate (CCA) and Chromated Copper Borate (CCB). Both are applied to the wood through the vacuum-pressure process, which in theory could increase the amount of surface defects and decrease the values of the physicalmechanical properties of the wood. Currently, due to the availability in the market (due to the implantation of certified areas in Brazil) of medium to low density wood species, the question of the need for preservation against biological demand is an aspect of fundamental importance to ensure the alternatives of supply of this material for the construction of structures, whose durability is equivalent to the wood of species of consecrated use, such as Jatobá, Sucupira, Garapa and Itaúba, for example In this context, the present work had as objective to investigate the influence of the treatments with the preservatives CCA and CCB on physicalmechanical properties of the following species of Brazilian tropical woods: Simarouba amara (C20), Cedrelinga catenaeformis (C30) e Erisma uncinatum Warm (C40), chosen in an attempt to cover the three lower resistance classes, according to what ABNT NBR 7190:1997 prescribes. The complete characterization of each species in the three types of treatments (No treatment -Ref: CCA; CCB) was performed for the subsequent application of the Tukey'smultiple comparison test, evaluated at the 5% level of significance. To evaluate the behavior of the preservatives at the cellular level, photomicrographs were generated by Scanning Electron Microscopy (SEM) and their respective EDS spectra. The results obtained showed that both chemical treatments did not affect significantly the values of the physicalmechanical properties of the studied species.