Open AccessPhotodegradation Properties of Earlywood and Latewood Spruce Timber Surfaces
Author(s) -
Edina Preklet,
László Tolvaj,
Satoru Tsuchikawa,
Dénes Varga
Publication year - 2021
Publication title -
acta silvatica and lignaria hungarica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.202
H-Index - 11
eISSN - 1787-064X
pISSN - 1786-691X
DOI - 10.37045/aslh-2021-0001
Subject(s) - photodegradation , lignin , picea abies , irradiation , degradation (telecommunications) , fourier transform infrared spectroscopy , chemistry , infrared spectroscopy , infrared , materials science , botany , chemical engineering , organic chemistry , optics , catalysis , photocatalysis , biology , telecommunications , physics , computer science , nuclear physics , engineering
Spruce (Picea abies Karst.) samples were irradiated using an ultraviolet light emitter mercury vapour lamp. The examined specimen surfaces contained earlywood or latewood to determine the photodegradation properties of these two tissue types. The generated chemical changes were monitored by diffuse reflectance Fourier transformed infrared spectroscopy. The difference spectrum method was used to present absorption changes. The earlywood suffered considerably greater degradation than the latewood during the UV irradiation. Most of the lignin molecules in the examined surface layer degraded during the first 11 days of UV irradiation for both earlywood and latewood. Results demonstrated that two types of unconjugated carbonyls absorbing at 1705 and 1764 cm–1 wavenumbers were created during the photodegradation. Time dependence of the absorption changes showed correlation between the guaiacyl lignin degradation and the generation of unconjugated carbonyl group absorbing at 1764 cm–1 wavenumber.