VENEER AND PLYWOOD PRODUCTION OF GUAPURUVU WOOD (Schizolobium parayba Blake.) COMING FROM A MIXED PLANTATION OF BRAZILIAN TREE SPECIES

Abstract

The objective of this study was to evaluate the potential of the guapuruvu wood (Schizolobium parayba), coming a mixed plantings of Brazilian native species, for veneer and plywood production. The peeling yield was 61%, linking green veneer and peeling wood. The obtained veneers, after clipped and dried, they were graded according to Brazilian Standards (NBR 9531/1986). The following grades o veneer were obtained: 2% of grade A, 24% of grade B, 48% of grade C and 26% of grade D. After, it was manufactured plywood of grade B/C/B, glued with urea-formaldehyde adhesive, and their properties of static bending (MOR and MOE) and bonding line strength in shear test (dry and wet) were appraised. Treatments (1, 2 and 3) varied according to the formulation of the glue (35, 50 and 65% of wheat flour in relation to the pure adhesive). The results indicated that the guapuruvu wood has potential for veneer and plywood production. The plywood showed significant difference between treatments in the static bending (perpendicular MOR) and shear (dry and wet). The plywood presents possibility of interior and intermediate use for the formulations 1 and 2, and interior use for the formulation 3. The plywood has potential for use in furniture, packing and box factory.