Effects of different naturally occurring defects on the some technological properties of plywood and particleboard

In this study, physical (density, moisture amount, thickness and increasing ratio) and mechanical (modulus of rupture, modulus of elasticity, internal band strength and shear tensile strength) properties of plywood and particleboard obtained from normal logs and logs having reaction wood defects, knots defect and double heart defect were examined. Also anatomic properties of normal and defective logs were determined.As a result of study; it was determined that usage of defective log in production of particleboard has no effect on density and moisture amount, but it is effective in thickness increasing values. Moreover, least values were found in board produced from logs having double heart defect and highest values were found in board produced from log with reaction wood. Normal log usage made a positive effect on modulus of rupture, modulus of elasticity and internal band strength values.It was determined that usage of defective log in plywood production has no efffect on physical properties. Usage of normal log has positive effect on modulus of rupture, modulus of elasticity and shear tensile strength.