摘要
以I-214杨木单板为试材、氙光作为辐射光源,考察I-214杨木单板在100h光照过程中试材表面材色的变化规律;依据红外光谱图的谱峰位置和谱峰相对吸收强度,分析和确定光变色过程中杨木木材的化学组分。结果表明:杨木木材受光辐射易发生变色,主要表现为明度指数L*降低,色度指数a*、b*上升;若以波数1510cm-1为基准,非共轭羰基C?O振动的吸收峰(1738cm-1)吸收强度显著增强;共轭羰基C?O伸缩振动的吸收峰(1650cm-1)有所增强;芳香环骨架C—C振动的吸收峰(1510cm-1)吸收强度明显减弱;C—O—H振动的吸收峰(1160~1052cm-1)吸收强度有所减弱。
In this study,veneers of I-214 poplar (Populus euramericana cv. I-214) were irradiated by Xenon fade meter,and the photo-discoloration mechanism was explored. Based on the peak positions of FTIR spectra and relative changes in absorbance intensity,the changes in chemical compositions of wood veneer during photo-discoloration were analyzed and determined. Results indicated that poplar wood was susceptible to photo-discoloration by light irradiation,which was indicated by the decrease in lightness index(L~) and increase in chromaticity indexes(a and b~). By comparison of the FTIR spectra of veneers subjected to irradiation for 100 hours and untreated samples,the relative intensity of peak at 1 738 cm -1 characterized by non-conjugated carbonyl group(C═O) increased remarkably,and the conjugated carbonyl group (1 650 cm -1 ) showed little increase in absorbance. Simultaneously,the absorbance peak at 1 510 cm -1 characterized by C—C stretching vibration of aromatic rings was weakened remarkably,the absorbance at 1 160-1 052 cm -1 corresponding to C—O—H vibration also decreased slightly.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2010年第1期89-91,共3页
Journal of Beijing Forestry University
基金
“十一五”国家科技支撑计划项目(2006BAD18B06)
“948”国家林业局引进项目(2006-4-C04)
关键词
I-214杨木
光变色
红外光谱
光变色机理
I-214 poplar veneer
photochrimism
FTIR spectra
photo-discoloration mechanism