Band Assignment and Classification of Lignin IR Spectra

The band wavenumbers in Table 4.1.1 were obtained at 4 cm-1 resolution. The intensity values shown in the parentheses were obtained from baseline-corrected and standardized spectra (Figs. 4.1.6 and 4.1.7). As shown in Fig. 4.1.7, most IR bands are common to the three main lignin types although their intensities may differ. In the wavenumber range 2700-3700cm-1, the band intensities of all lignin types are similar (Table 4.1.1, Fig. 4.1.6). 

A semi-quantitative comparison of band intensities can be used for lignin classification as first described by Kawamura and Higuchi (1964a,b). 

Wavenumbers (cm ) No in Band origin, short comments Maxima at cm, % absorbance (% A) from  

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