Reduction of weathering degradation of wood through plasma-polymer coating

A novel plasma-enhanced coating for wood substrates has been developed which diminishes the degradation of wood under simulated harsh environmental conditions. Reflective (zinc oxide) and electromagnetic radiation (EMR)-absorbent (benzotriazole, 2-hydroxybenzophenone, phtalocyanine, and graphite) substances were incorporated into a liquid phase, high-molecular-weight polydimethylsiloxane and deposited as thin layers on wood surfaces. The macromolecular films, containing the dispersed materials, were then converted into a three-dimensional solid state network by exposure to a 30 kHz-oxygen-RF-plasma. The discharge induced chemistry and altered surface topographies in the surface layers were monitored by survey and high resolution Electron Spectroscopy for Chemical Analysis, Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscopy. The surface characteristics and the resistance to weathering of the plasma treated substrates were evaluated and compared to the properties of un-modified samples.