Wood in outdoor application undergoes various degradation processes such as degradation throughout biological processes as well as weathering processes. In outdoor use wood is exposed to natural weathering and undergoes different structural and chemical changes. These lead in a decomposition of wood. Wood modification approaches could overcome these drawbacks, wood properties could be improved and the opportunities for utilization are enlarged. This study deals with the approach to protect wood surfaces by pyrolysis, because the decomposition of charcoal required a higher intensity of radiation as native wood. Therefore, the behavior of Spruce wood (Picea abies) with carbonized covering layer under artificial weathering was determined. The pyrolysis layers were generated on the wood surfaces through a targeted heat treatment by use of a special wood pyrolysis machine. Spruce samples were pyrolized to receive carbonized covering layer of varying thickness and subsequently they were exposed to artificial weathering for eight weeks. In order to investigate color and chemical changes, color measurements were carried out stepwise during weathering and FTIR measurements were done before and after the weathering test. The results indicate that the carbonized surfaces undergo a lower decomposition under weathering than the native wood surface. In addition, the study shows that the thickness of the carbonized covering layer plays an important role for protecting wood for decomposition by weathering.
Keywords: artificial weathering, color changes, pyrolysis, ATR FTIR
Authors
Kampe, A.
Eberswalde University for Sustainable Development – University of Applied Sciences, Eberswalde, Germany
Murr, J.
Eberswalde University for Sustainable Development – University of Applied Sciences, Eberswalde, Germany
Peters, T.
Eberswalde University for Sustainable Development – University of Applied Sciences, Eberswalde, Germany
Günther, M.T.
Eberswalde University for Sustainable Development – University of Applied Sciences, Eberswalde, Germany
Pfriem, A.
Eberswalde University for Sustainable Development – University of Applied Sciences, Eberswalde, Germany
Login to download the PDF