Influence of atmospheric pressure plasma jet and diffuse coplanar surface barrier discharge treatments on wood surface properties: A comparative study

Beech and larch substrates were successfully treated by an atmospheric pressure plasma jet (APPJ) or a diffuse coplanar surface barrier discharge (DCSBD) system. Applying both technologies on wood, more hydrophilic properties were achieved, potentially by the degradation of hydrophobic extractives, the generation of polar functional groups and a modification of surface roughness. Comparing both plasma systems, the hydrophilization effect was stronger using the APPJ. The formation of polar groups on the surface was detected by X-Ray photoelectron spectroscopy. Investigated by scanning electron microscopy, APPJ further showed a more distinct impact on surface morphology compared to DCSBD. Following natural aging, plasma treatment effects such as hydrophilicity were partially reduced and the recovery was more pronounced for larch wood compared to beech. [GRAPHICS] .