Research Article
Mixture Design Approach on the Physical Properties of Lignin-Resorcinol-Formaldehyde Xerogels
Table 7
Position and attribution of the IR absorption bands for lignin and xerogels.
| Wavenumber (cm1) | Band attribution |
| 3412–3012 | (OH) | 2850–3006 | (CH2) | 2850 | (CH2) in aromatic methoxy groups | 1710 | (C=O) not conjugated | 1670 | (C=O) conjugated ketones | 1594–1613 | (C=C) aromatic rings | 1510 | (C=C) aromatic rings | 1460 | (CH2) and (CH3) | 1420 | (scissors) (CH2) and (CH3) | 1375 | (CH3) | 1330 | (CH2) and (O–H) | 1262 | (C–O) | 1220 | (C–O) | 1080 | (C–O) in secondary alcohols and aliphatic ethers | 1034 | (C–O–C) | 810–902 | (C–H) out of plane of aromatic rings and (C–C) in rings |
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: stretch; : deformation; : rocking; sy: symmetrical; as: asymmetrical; s: shoulder; l: exclusive peak for lignin; x: exclusive peak for xerogels.
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