Surface Energy Modification by Radiofrequency Inductive and Capacitive Plasmas at Low Pressures on Sugar Maple: An Exploratory Study


  • Vincent Blanchard
  • Pierre Blanchet
  • Bernard Riedl


Surface energy surface properties, plasma, adhesion, sugar maple, wettability, ICP, CCP, mechanical properties, wood, confocal Raman spectroscopy, XPS


The wood products industry is going through hard times in both Canada and the US. It is faced with competition from emerging economies and substitution products. The North American economy is slowing down with decreasing demand for wood products. Under these conditions, the industry should be innovative and develop the next generation of wood products. Plasma technology could be used to improve wood surface properties and compensate for the variations to be expected from an organic living material, which is sensitive to its environment (moisture, water, temperature, ultraviolet light). In recent years, the plastic and textile industries have begun experimenting with plasma technology to activate surfaces, mainly to improve coating/substrate adhesion. The literature on potential applications of plasma treatment to wood surfaces is very limited. This report describes the results of an exploratory study on the effect of plasma treatments on sugar maple wood using different gases and mixtures (N2, H2, O2, and Ar) at different pressures (13.3-665 Pa). Water wettability and adhesion between surface and waterborne polyurethane acrylate coatings were also studied. The results show that it was possible, under certain conditions, to significantly increase wood/coating adhesion by 30-100%. This improvement is correlated with improvements in wood surface energy and coating penetration depth. In addition, chemical analyses showed that, with some plasma types, the treatment led to new atoms being grafted.


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