University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Johannes Tieben
(2018):
In situ Chemosynthese von ZnO-Nanopartikeln in Buchen- und Pappelholz.
Master / Diploma Thesis - Institut für Holztechnologie und Nachwachsende Rohstoffe,
BOKU-Universität für Bodenkultur,
pp 42.
UB BOKU
obvsg
FullText
- Abstract:
- In recent years numerous publications have demonstrated positive influence of inorganic nanoparticles (ZnO, TiO2) on the UV-stability of wood. In this thesis beech wood (Fagus sylvatica) was modified by using Zn(NO3)2*6H2O and NaOH, to provoke in-situ synthesis of ZnO-particles. The weight percent gain (WPG) in dependence of the concentration of Zn2+-ions in the impregnation solution, and the influence of ZnO on UV as well as moisture-resistance were investigated. In addition, an electron microscope analysis and an infrared (IR) analysis were both carried out. The microscopic analysis showed ZnO-particles precipitated in vessels and fibres. The number of observed particles increased with higher concentrations of Zn2+ in the impregnation solution. WPG measurements showed that the sample weights increased with higher Zn2+-concentrations. Equilibrium moisture content (EMC) measurements indicated no improvement of the moisture-resistance. EMC for ZnO-impregnated specimens were higher than for untreated specimens. Infrared-spectroscopy as well as gravimetric measurements indicated severe wood degradations due to the alkaline treatment. Significant UV-stability improvement of impregnated specimens was not shown. Due to the severe wood degradation the applied process turned out to be unsuitable to achieve better UV- and moisture-resistance for beechwood.
- Beurteilende(r): Wimmer Rupert