Production of particleboard using tannin-based phenol formaldehyde adhesive

Tannins are the most desirable natural, and renewable phenol compound obtained from plan. The phenolic nature of tannins causes this material to react with formaldehyde and form tannin-formaldehyde resins. Wheat straw and forest residues were used for the manufacture of particleboard (with a ratio of about 50 to 50 percent) using tannin formaldehyde based resin. Either 10 or 20% (based on the dry weight of the phenol formaldehyde resin was added to 35% formaldehyde solution to make the glue. Particleboards were prepared at two thicknesses of 10 and 16 mm and then the properties of the boards including bending strength, modulus of elasticity, internal bonding, thickness swelling and water absorption were measured. The results showed that the strength properties of the fabricated boards from combined particles were lower than those from wood particles only. Also, increasing the tannin dosage to phenol formaldehyde resin led to the increased internal bonding, swelling and water absorption (2 and 24 hours) of the boards