Official Journal of the Japan Wood Research Society
Table 3 FT-IR characteristic bands assignments for SPF precipitated lignin compared to hardwood
Absorption band location (cm−1)* | Type of vibration in different absorption bands | SPF wavenumber (cm−1) | E. pellita’s wavenumber (cm−1) | Birch’s wavenumber (cm−1) [68] |
|---|---|---|---|---|
3500–3100 | Stretching vibrations of alcoholic and phenolic OH groups involved in hydrogen bonds | 3341–3131 | 3433–3107 | 3273–3393 |
2937 and 2850 | Stretching vibrations of C–H bonds of the methyl and methylene groups | 2943 and 2841 | 2939 and 2842 | 2937 and 2928 |
1715–1710 | Non-conjugated carbonyl | 1713 | – | 1712–1715 |
1665–1655 | Conjugated carbonyl | – | – | – |
1605–1595, 1515–1500 and 1430–1425 | Aromatic ring vibrations | 1607, 1514, and 1425 | 1605, 1518, and 1426 | 1590–1607, 1515–1420 |
1340–1330 | Vibrations of syringyl rings and stretching vibrations of C–O bonds | 1327 | 1327 | 1328 |
1272–1220 | Vibrations of guaiacyl rings and stretching vibrations of C–O bonds | 1269–1217 | 1217 | – |
1150–1140 | Deformation vibrations of C–H bonds in guaiacyl rings | – | 1151 | – |
1125 | Deformation vibrations of C–H bonds in syringyl rings | – | – | – |
1085 | Deformation vibrations of C–O bonds in secondary alcohols and aliphatic ethers | – | – | – |
1130–1035 | Deformation vibrations of C–H bonds in the aromatic rings and deformation vibrations of C–O bonds in primary alcohols | 1115–1040 | 1116–1032 | – |
945 and 870–850 | Deformation vibrations of C–H bonds in associated with aromatic rings | 829 | 828 | 890–830 |
430–600 | Stretching vibrations of C–S bonds | – | – | 600–430 |