RECONSTITUTED PARTICLEBOARDS FROM CCA-TREATED RED PINE UTILITY POLES

Substantial quantities of waterborne preservative-treated wood have be en produced in the last few decades. The preservative most used has be en chromated copper arsenate (CCA). Soon large quantities of CCA-treat ed wood will come out of service and require disposal. The current dis posal options for CCA-treated wood are both ecologically unacceptable: landfill or incinerate. Manufacturing wood composites from CCA-treate d wood is a viable option to produce sheathing or flooring for risk-de cay applications. The objective of this study was to investigate the e ffect of increased CCA-treated wood content on some of the mechanical and physical properties of resulting particleboards. Furnish from CCA- treated red pine utility poles was mixed with untreated furnish at fiv e percentage levels: 100, 75, 50, 25, and 0. Eighty boards were produc ed with phenol-formaldehyde resin at 4 and a percent solids resin cont ent. Modulus of elasticity, modulus of rupture, and internal bond of t he boards decreased as the content of CCA-treated furnish increased. T hickness swelling and water absorption tests showed that there were no significant differences among boards made with various proportions of CCA-treated furnish. A leaching test removed low amounts of chromium, copper, or arsenic metals. An addition of 50 percent CCA-treated furn ish can be used without significantly affecting the board properties.