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Official Journal of the Japan Wood Research Society

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Contribution of lignin to the reactivity of wood in chemical modifications II: influence of delignification on reaction with vaporous formaldehyde

Abstract

Participation of lignin in the reaction between vapor-phase formaldehyde and wood was examined by using gradually delignified wood meal. A fi rst-order rate equation was successfully applied to the weight gain data. From the estimated reaction parameters such as rate constant, k, and ultimate weight gain, a, the reactivity toward formaldehyde was discussed among wood components, and compared with that for acetylation. k decreased monotonously with progress of the elimination of lignin, suggesting that the reaction rate of lignin is dominant over that of whole wood, and the decrease in the ratio of lignin retarded the reaction of wood as a whole. On the other hand, a increased with decreasing lignin content. This may be attributable to the enhanced reactivity of the remaining lignin due to some structural changes and to the increase in the number of reactive sites in polysaccharides as a result of their exposure accompanying the elimination of lignin. The dependencies of k and a on the lignin content were not similar to the case for acetylation, probably because of the difference in the reaction phase. In vapor-phase formaldehyde treatment, the remaining lignin reacts as it is, whereas in liquid-phase acetylation it would undergo rearrangement or swelling of the structure in the reaction solution.

References

  1. Minato K, Shimizu R, Kawaguchi S (2007) Contribution of lignin to the reactivity of wood in chemical modifications I: influence of delignification on acetylation. J Wood Sci DOI 10.1007/s10086-006-0847-7

  2. Minato K, Okamura K, Okamoto H (1971) A simplified model for the reaction mechanism of cellulose with formaldehyde vapor. Mokuzai Gakkaishi 17:449–455

    CAS  Google Scholar 

  3. Minato K (1984) The HCl-catalyzed reaction of cotton cellulose with vaporous formaldehyde. Mokuzai Gakkaishi 30:546–552

    CAS  Google Scholar 

  4. Norimoto M (1988) Acetylated wood (in Japanese). Wood Res Tech Note Wood Res Inst Kyoto Univ 24:13–30

    CAS  Google Scholar 

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Correspondence to Kazuya Minato.

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Minato, K., Hosoo, H. & Kawaguchi, S. Contribution of lignin to the reactivity of wood in chemical modifications II: influence of delignification on reaction with vaporous formaldehyde. J Wood Sci 53, 255–257 (2007). https://doi.org/10.1007/s10086-006-0845-9

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  • DOI: https://doi.org/10.1007/s10086-006-0845-9

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