Chemical reactivity of heat-treated wood
2007
Pétrissans, Mathieu | Nguila Inari, G. | Gérardin, Philippe | Laboratoire d’Etude et de Recherche sur le Matériau Bois (LERMAB) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université Henri Poincaré - Nancy 1 (UHP)
International audience
显示更多 [+] 显示较少 [-]英语. Chemical reactivity of heat-treated wood was compared with that of untreated wood. For this purpose, heat-treated pine or beech sawdust was reacted with different carboxylic acid anhydrides in pyridine or with phenyl isocyanate in dimethyl formamide. Compared to controls, weight gains obtained with heat-treated sawdust are smaller showing a lower chemical reactivity. FTIR analyses of lignin and holocellulose fractions, isolated after acidic hydrolysis of polysaccharides or delignification with sodium chlorite, indicate that both components are involved in the reactions. Compared to lignin, holocellulose exhibits important infrared absorptions of about 1,730 cm–1, characteristic of ester or urethane linkages formed. Lower reactivity of heattreated sawdust is explained by the decrease in free reactive hydroxyl groups in holocellulose due to the thermal degradation of hemicelluloses, considered more reactive than cellulose.
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