Journal of Wood Science

, Volume 62, Issue 1, pp 12–19 | Cite as

Difference in reduction properties between longitudinal dimension and elastic modulus of wood induced with aqueous NaOH treatment: modeling and analysis

Original article

Abstract

The dependence of the elastic modulus and the longitudinal contraction on the NaOH fractional concentration [NaOH], which differs from each other, was discussed based on a quantitative model analysis using the rule of mixtures, a cell wall model, and a dual-phase model consisting of crystal and amorphous phases. The elastic modulus was formulated as a function of the degree of crystallinity of the decrystallized microfibrils. The [NaOH] dependence of the calculated elastic modulus shows good agreement with the experimental results in that the [NaOH] dependence differs before and after at [NaOH] = 0.12. The model analysis illustrates that the reduction property of the elastic modulus is dependent on whether the amorphous region created with the treatment transverses the originally crystalline region of the microfibrils or not: the concentration is [NaOH] = 0.12. This is attributed to the difference in the reduction property between the elastic modulus and the dimensional changes along the longitudinal axis of a wood sample at [NaOH] < 0.12.

Keywords

Mercerization Elastic modulus Contraction Modeling Simulation 

References

  1. 1.
    Jeffries R, Warwicker JO (1969) The function of swelling in the finishing of cotton. Text Res J 1:548–559Google Scholar
  2. 2.
    Schniewind AP (1972) Elastic behaviour of the wood fiber. In: Jayne BA (ed) Theory and design of wood and fiber composites materials. Syracuse University Press, New York, pp 83–96Google Scholar
  3. 3.
    Stöckmann VE (1971) Effect of pulping on cellulose structure Part I. Tappi 54:2033–2037Google Scholar
  4. 4.
    Stöckmann VE (1971) Effect of pulping on cellulose structure Part II. Tappi 54:2038–2045Google Scholar
  5. 5.
    Nakano T, Sugiyama J, Norimoto M (2000) Contraction force and transformation of microfibril with aqueous sodium hydroxide solution. Holzforschung 54:315–320CrossRefGoogle Scholar
  6. 6.
    Ishikura Y, Nakano T (2007) Contraction of the microfibrils of wood treated with aqueous NaOH. J Wood Sci 53:175–177CrossRefGoogle Scholar
  7. 7.
    Nakano T (2010) Mechanism of microfibril contraction and anisotropic dimensional changes for cells in wood treated with aqueous NaOH solution. Cellulose 17:711–719CrossRefGoogle Scholar
  8. 8.
    Nakano T, Tanimoto T, Hashimoto T (2013) Morphological change induced with NaOH-water solution for ramie fiber: change mechanism and effects of concentration and temperature. J Mater Sci 48:7510–7517CrossRefGoogle Scholar
  9. 9.
    Nakano S, Nakano T (2015) Morphological changes induced in wood samples by aqueous NaOH treatment and their effects on the conversion of cellulose I to cellulose II. Holzforschung 69:483–491CrossRefGoogle Scholar
  10. 10.
    Tanimoto T, Nakano T (2013) Side-chain motion of components for wood samples partially non-crystallized with NaOH aqueous solution. Mater Sci Eng C 33:1236–1241CrossRefGoogle Scholar
  11. 11.
    Fengel D, Jakob H, Strobel C (1995) Influence of the alkali concentration on the formation of cellulose II. Holzforschung 49:505–511CrossRefGoogle Scholar
  12. 12.
    Nakano T (1989) Plasticization of wood by alkali treatment. Relationship between plasticization and the ultra-structure. Mokuzai Gakkaishi 35:431–437Google Scholar
  13. 13.
    Fujimoto T, Nakano T (2000) The effect of mercerization on wood structure features (in Japanese). Mokuzai Gakkaishi 46:238–241Google Scholar
  14. 14.
    Watanabe U, Norimoto M (2000) Three dimensional analysis of elastic constants of the wood cell wall. Wood Res 87:1–7Google Scholar
  15. 15.
    Hill R (1964) Theory of mechanical properties of fiber-strengthened materials. 1. Elastic behavior. J Mech Phys Solids 12:199–212CrossRefGoogle Scholar
  16. 16.
    Habip LM (1965) A review of recent work on multilayered structures. Int J Mech Sci 7:589–593CrossRefGoogle Scholar
  17. 17.
    Tang RC, Hsu NN (1973) Analysis of the relationship between microstructure and elastic properties of the cell wall. Wood Fiber 5:139–151Google Scholar
  18. 18.
    Ohgama T, Yamada T (1974) Elastic modulus of porous materials (in Japanese). Mokuzai Gakkaishi 20:166–171Google Scholar
  19. 19.
    Lekhnitskii SG (1963) Theory of elasticity of an anisotropic elastic body. Holden-Day, San Francisco, pp 1–73Google Scholar
  20. 20.
    Cousins WJ (1978) Young’s modulus of hemicellulose as related to moisture content. Wood Sci Technol 2:161–167CrossRefGoogle Scholar
  21. 21.
    Gindl W, Martinschitz KJ, Boesecke P, Keckes J (2006) Changes in the molecular orientation and tensile properties of uniaxially drawn cellulose films. Biomacromolecules 7:3146–3150CrossRefPubMedGoogle Scholar
  22. 22.
    Sakurada I, Nukushina Y (1962) Experimental determinations of the elastic modulus of crystalline regions in oriented polymers. J Polym Sci 57:651–660CrossRefGoogle Scholar
  23. 23.
    Abe K, Yano H (2009) Comparison of the characteristics of cellulose microfibril aggregates of wood, rice straw and potato tuber. Cellulose 16:1017–1023CrossRefGoogle Scholar
  24. 24.
    Crank J (1975) The mathematics of diffusion, 2nd edn. Oxford Sci Publication, New York, pp 44–68Google Scholar
  25. 25.
    Norimoto M, Takabe K (1985) On noncrystalline structure of wood. Wood Res Tech Notes 21:96–101Google Scholar

Copyright information

© The Japan Wood Research Society 2015

Authors and Affiliations

  1. 1.Asahi Woodtech CompanyOsakaJapan
  2. 2.Professor EmeritusKyoto UniversityKyotoJapan

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