TSubstantiation of the Interaction Mechanism of Wood Components and Water

Complete text of the article:

Download article (pdf, 1.1MB )

UDС

UDС 621.3.029.6:674.8

DOI:

10.17238/issn0536-1036.2017.3.152

Abstract

The physical and mechanical properties of wood depend on the amount of moisture in the cell walls, associated with its components. However, we still have no clear idea of the location of bound moisture in the wood substance of the cell walls. The goal of research is to substantiate theoretically the sorption ability of wood components and to simulate this process at the nanoscale, taking into account the size of molecules and atoms. We consider cellulose as the main and most studied component of wood for modeling. The developed spatial
spherical model of the cellulose macromolecule and the arrangement of its building blocks in the unit cell make it possible to explain the mechanism of moisture absorption by the cell wall of wood at the molecular level. The hydroxyl groups of cellulose macromolecules and water molecules are of one nature, since the electronegativity of their constituent
atoms is the same, which allows them to form easily the intermolecular hydrogen bonds in one layer and between adjacent layers in the crystal. The hydrogen bond is electrostatic in nature. Its energy is about 10 times less than the energy of interatomic covalent bonds. The electronegativity of OH-groups of cellulose and water molecules coincide in importance;
therefore, under certain energy conditions of the environment, the water molecule, breaking the intermolecular hydrogen bond of the cellulose molecule, immediately closes it on itself. Similarly, the water molecule leaves the hydrogen bond, if it has sufficient kinetic energy to move. The penetration of water molecules into a cellulose crystal occurs by moving them from one hydrogen bond to another. Water molecules are retained in these bonds only due to their electronegativity. Thus, the interaction mechanism of cellulose microcrystalline with moisture is determined by the fact that water molecules are retained in the hydrogen bonds of the hydroxyl groups of the glucopyranose units of the cellulose macromolecule and are
able to move between them. When the water molecule is introduced into the hydrogen bond, the distance between the OH-groups of cellulose is increased by its size; and at a moisture
absorption the swelling of the cellulose crystalline structure is about 12 %. Water molecules form hydrogen bonds with lignin and hemicellulose in the same way as with cellulose. The
calculation, made through the molecular masses of building blocks of macromolecules,
demonstrates, that the maximum quantitative content of physically bound moisture in wood is about 30 %, which corresponds to numerous experimental data of other researchers.

Authors

V.I. Vrublevskaya, Doctor of Engineering Sciences, Professor V.O. Matusevich, Candidate of Engineering Sciences V.V. Kuznetsova, Assistant

Affiliation

Belarusian State University of Transport, ul. Kirova, 34, Gomel, 246653, Republic of Belarus; e-mail: vmatusevich@yandex.ru

Keywords

wood, cellulose, lignin, absorption, bound moisture, hydrogen bond, microcrystallite, electronegativity.

For citation

Vrublevskaya V.I., Matusevich V.O., Kuznetsova V.V. Substantiation of the Interaction Mechanism of Wood Components and Water. Lesnoy zhurnal [Forestry journal], 2017, no. 3, pp. 152–163. 10.17238/issn0536-1036.2017.3.152

References

1. Borovikov A.M., Ugolev B.N. Spravochnik po drevesine [Wood Reference]. Moscow, 1989. 296 p. 2. Sommer K., W?nsch K.-H., Zettler M. Wissensspeicher Chemie. Berlin, 1998. 384 p.
3. Levitina T.P. Spravochnik po organicheskoy khimii [Handbook of Organic Chemistry]. Saint Petersburg, 2002. 448 p.
4. Sarkanen K.V., Ludwig C.H., eds. Lignins: Occurrence, Formation, Structure and Reactions. New York, 1971. 916 p. 5. Matusevich V.O. Strukturnye izmeneniya kletochnykh stenok drevesiny i ikh rol' v intensifikatsii SVCh-sushki drevesnykh vkladyshey podshipnikov skol'zheniya: dis. … kand. tekhn. nauk [Structural Changes in the Cell Walls of Wood and Their Role in the Intensification of Microwave Drying of Wood Plain Bearing Liners: Cand. Eng. Sci. Diss.]. Gomel, 2011. 130 p.
6. Nevzorova A.B., Vrublevskiy V.B., Matusevich V.O., Vrublevskaya V.I. Podshipniki skol'zheniya samosmazyvayushchiesya na osnove modifitsirovannoy drevesiny (teoriya, tekhnologiya i praktika) [Self-Lubricating Plain Bearings on the Basis of Modified Wood (Theory, Technology and Practice)]. Gomel, 2011. 254 p. 7. Nikitin V.M., Obolenskaya A.V., Shchegolev V.P. Khimiya drevesiny i tsellyulozy
[Chemistry of Wood and Cellulose]. Moscow, 1978. 368 p. 8. Perelygin L.M., Ugolev B.N. Drevesinovedenie [Wood Science]. Moscow, 1971. 286 p. 9. Rabinovich V.A., Khavin Z.Ya. Kratkiy khimicheskiy spravochnik [Brief Chemical Handbook]. Leningrad, 1977. 376 p. 10. Rogovin Z.A., Shorygina N.N. Khimiya tsellyulozy i ee sputnikov [Chemistry of Cellulose and Its Satellites]. Moscow; Leningrad, 1953. 679 p. 11. Sergovskiy P.S., Rassev A.I. Gidrotermicheskaya obrabotka i konservirovanie
drevesiny [Hydrothermal Processing and Preserving of Wood]. Moscow, 1987. 360 p. 12. Ugolev B.N. Drevesinovedenie i lesnoe tovarovedenie [Wood Science and Forest Commodity Science]. Moscow, 2006. 270 p. 13. Browning B.L., ed. The Chemistry of Wood. New York, 1963. 689 p. 14. Chudinov B.S. Voda v drevesine [Water in Wood]. Novosibirsk, 1984. 272 p.
15. Baker A.A., Helbert W., Sugiyama J., Miles M.J. Surface Structure of Native Cellulose Microcrystals by AFM. Applied Physics. A: Materials Science and Processing,
1998, vol. 66, iss. 7, pp. 559–563.
16. Horikawa Y., Itoh T., Sugiyama J. Preferential Uniplanar Orientation of Cellulose Microfibrils Reinvestigated by the FTIR Technique. Cellulose, 2006, vol. 13, iss. 3, pp. 309–316. 17. O'Sullivan A.C. Cellulose: the Structure Slowly Unravels. Cellulose, 1997, no. 4, pp. 173–207.
18. Zugenmaier P. Crystalline Cellulose and Cellulose Derivatives: Characterization and Structures. Berlin, 2008. 285 p. Received on January 26, 2017