Surface characterization of chromated copper arsenate (CCA)-treated red maple

Red maple wood blocks were treated with chromated copper arsenate (CCA) preservative. The surface quality of both treated and untreated wood was characterized by various analytical techniques. Environmental scanning electron microscopy (ESEM) showed deposits of metal oxides on the cell wall of CCA-treated wood. X-ray photoelectron spectroscopy (XPS) indicated a higher oxygen/carbon ratio on the surface for CCA-treated wood than for untreated controls or water-treated samples. The surface of CCA-treated wood was rougher than that of untreated and water-treated wood. Higher contact angles for CCA-treated wood with water, glycerol, and phenol-formaldehyde adhesive compared with untreated wood indicated poor wettability and a hydrophobic surface, which may partially explain why composites made of CCA-treated wood exhibit low performance, particularly in exterior applications.