Summary
The variation of the longitudinal Young's modulus with mean cellulose microfibril angle of the wood substance of the earlywood of a softwood has been determined from small clear samples.
The longitudinal Young's modulus falls steeply as the angle between the longitudinal axis and the mean microfibril direction in the cell walls increases. The variation has been explained in both form and magnitude by applying the elastic theory of a fibre composite material with distributed fibre directions to a model of the experimental material. It confirms the two phase concepts of the plant cell wall, as far as the elastic properties are concerned, of rigid crystalline microfibrils embedded in an isotropic matrix of amorphous and paracrystalline materials.
Zusammenfassung
Die Änderung des Young-Moduls in longitudinaler Richtung mit dem mittleren Winkel der Cellulose-Mikrofibrillen in der Frühholzsubstanz von Nadelholz wurde an kleinen, fehlerfreien Proben bestimmt.
Der longitudinale Young-Modul fällt mit zunehmendem Winkel zwischen Längsachse und mittlerer Mikrofibrillen-Richtung in der Zellwand steil ab.
Die Änderung wurde nach Form und Größe durch Anwendung der Elastizitätstheorie für ein faseriges Material mit wechselnden Faserrichtungen auf ein Modell aus dem Versuchsmaterial erklärt. Das Zwei-Phasen-Modell der Pflanzenzellwand wird damit bestätigt, soweit es sich um die elastischen Eigenschaften von starren, kristallinen Cellulose-Mikrofibrillen handelt, die in einer isotropen Matrix aus amorphem, parakristallinen Material eingebettet sind.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Barber, N. F., and B. A. Meylan: The Anisotropic Shrinkage of Wood. Holzforschung Bd. 18 (1964) p. 146/156.
Cave, I. D.: The Anisotropic Elasticity of the Plant Cell Wall. Wood Science and Technology Vol. 2 (1968) No. 4, p. 268/278.
Cowdrey, D. R., and R. D. Preston: Elasticity and Microfibrillar Angle in the Wood of Sitka Spruce. Proc. Roy. Soc. B. Vol. 166 (1966) p. 245/272.
Hearle, J. W. S.: The Fine Structure of Fibres and Crystalline Polymers. I. Fringed Fibril Structure. J. Appl. Polymer Vol. 7 (1963) p. 1175/1192.
Kelsey, K. E.: A Critical Review of the Relationship between the Shrinkage and Structure of Wood. Division of Forest Products Technological Paper No. 28 (1963) C.S.I.R.O., Australia.
Mark, R. E. in: Côté, W. A. (Ed.): Cellular Ultrastructure of Woody Plants. Syracuse 1965: Syracuse Univ. Press.
—: Cell Wall Mechanics of Tracheids. New Haven and London 1967: Yale Univ. Press.
Meredith, R.: Molecular Orientation and the Tensile Properties of Cotton Fibres. J. Text. Vol. 37 (1946) p. 469/480.
Meylan, B. A.: Measurement of Microfibril Angle by X-ray Diffraction. For. Prod. J. Vol. 17 (1967) p. 51/58.
Probine, M. C.: Spiral Growth and Cell Wall Structure of Nitella opaca. J. Expt. Bot. Vol. 14 (1963) p. 101/113.
Sadoh, T., and G. N. Christensen: Longitudinal Shrinkage of Thin Sections. Wood Science and Technology Vol. 1 (1967) p. 26/44.
Sakurada, I., Y. Nukushina and T. Ito: Experimental Determination of the Elastic Modulus of Crystalline Regions in Oriented Polymers. J. Polymer Sci. Vol. 57 (1962) p. 651/660.
Stamm, A. J.: Wood and Cellulose Science. New York 1964: Ronald Press.
Srinivasan, P. S.: The Elastic and Thermal Properties of Timber. Quart. J. Indian Vol. 4 (1941) p. 224/314.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cave, I.D. The longitudinal Young's modulus of Pinus radiata . Wood Science and Technology 3, 40–48 (1969). https://doi.org/10.1007/BF00349983
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00349983