Painéis de madeira de eucalipto: estudo de caso de espécies e precedências

Abstract

This work aimed at the evaluation of fifteen provenances coming from species of Eucalyptus cloeziana, Eucalyptus grandis and Eucalyptus saligna; in the manufacture of plywoods and particle boards. The basic density and chemical composition of the trees were measured initially. Six boards per modality of plate for each provenance were manufactured. In the veneers, phenol- formaldehyde resin with grammage of 320g/m2 with a pressing cycle of 15kfg/cm2, 150 C per ten minutes was utilized. In the particle boards, urea-formaldehyde with 8% weight of the board and pressing cycle of 40kgf/cm², 160C for 8 minutes utilized. In the physical tests of the plywoods, distinction for the species of Eucalyptus cloeziana e Eucalyptus saligna. For the mechanical tests, what parallel MOR is concerned, only some provenances managed to reach the demands of the norm; while in the comparative test between shear stress and wood failure, provenances 10634, 48 and 9753 did not meet any of the values established. The physical tests, in the particleboards, presented as a distinction the species of Eucalyptus cloeziana with decreased water absorption. In the thickness swelling, the precedence of Eucalyptus grandis with best performance was the 43 one. In the mechanical properties, distinction for Eucalyputs cloeziana as far as both compression and MOE are concerned, and for Eucalyptus grandis in the properties of MOE and MOR, standing out its origin of number 10695.