The main objective of this work was to produce particleboards with hydrolysed "angico-vermelho" bark (Anadenanthera peregrina) tannins as partial or total substitute of urea-formaldehyde. Particleboards with the dimensions of 15.75" x 15.75" x 0.39" were manufactured with Pinus elliottii particles and 8% of adhesive solids in relation to the dry mass of particles. Adhesives employed either 100% urea-formaldehyde or 12.5, 25 and 37.5% of tannin adhesive. Boards were also manufactured with pure tannin adhesives. The experimental design was constituted of five treatments and three repetitions. The particleboards average density was 0.7 g/cm³ (0.0618 oz/in³). Board properties were determined according to the ASTM D-1037 (1993) standards. The mechanical propertiy values were compared to the minimum values established by the ANSI/A 208.1 standards. Water absorption and thickness swelling values were compared to the maximum values established by the DIN 68m761 (1) standards. The mechanical properties of boards produced with the adhesives containing tannins of "angico-vermelho", except for the elasticity module, exceeded the minimum values requested by the ANSI/A1-280/93 standards. The water absorption and thickness swelling of all the boards exceeded the established maximum value after 2 and 24 h of immersion. It is ended that the adhesives of tannins of angico-vermelho can substitute partially or totally the commercial urea-formaldehyde adhesive and also that their mixtures are suitable for interior use, where resistance to humidity is not requested.
Tannins; particleboard; adhesives
