Summary
The effects of temperature and sulfonation on the deformation of spruce wood at conditions comparable to those during screw press impregnation prior to mechanical pulping were studied using a dynamic testing method. In addition to the physical properties of wood, shear fracture surfaces obtained at different deformation temperatures and at different sulfonation levels were studied using scanning electron microscopy (SEM).
The results showed that the failure energy of wood decreased gradually with increased deformation temperature in the tested range of 20–95 °C, due to thermal softening of the material. In addition to thermal treatment, the failure energy could also be reduced by sulfite treatment of the wood before deformation, and decreased with increasing sulfonation degree.
The SEM analysis showed that increasing the deformation temperature causes the fracture plane to travel around the fiber walls instead of through them, thus exposing a smoother wood surface with less fiber damage. At a given deformation temperature, particularly at the lower temperatures, sulfonation improves fiber separation.
Similar content being viewed by others
References
Axelson, P.;Simonson, R. 1982: Thermomechanical pulping with low addition of sulfite Part 1: Effects of mild sulfite treatment of spruce chips prior to defibration. Svensk Papperstidn. 85: R132-R139
Axelson, P.;Simonson, R. 1982: Thermomechanical pulping with low addition of sulphite. Paperi ja Puu-Paperr och Trä. 64: 729–733
Barbe, M. C.; Janknecht, S.; Sauriol, J. F. 1993: The importance of chip impregnation on refiner pulp quality. 18th Int. Mech. Pulp. Conf, Oslo, June 15–17, 17–37
Borgin, K. 1974: How wood fails under stress. New Scientist 64: 556–559
Fengel, D.;Wegener, G. 1989: Wood - chemistry, ultrastructure, reactions. pp 228. Walter de Gruyter, Berlin, New York
Goring, D. A. I. 1963: Thermal softening of lignin, hemicellulose and cellulose. Pulp Paper Mag. Can. 64: T517-T527
Höglund, H.;Sohlin, U.;Tistad, G. 1976: Physical properties of wood in relation to chip refining. Tappi 59: 144–147
Iwamida, T.;Yuichiro, S. 1980: Mechanisms of softening and refining in high yield sulfite pulping processes. Cellulose Chem. Technol. 14: 253–268
Johansson, L. 1993: The effect of temperature and sulfonation on the deformation of wood under torsional stress. pp. 11–20. Diploma thesis, Dept. Forest. Prod. Chem. Eng., CTH
Kojima, Y.;Kayama, T. 1983: 2nd Int. Symp. Wood Pulp. Chem., 23–27 May, Tsukuba science city, Japan, 11–17
Kojima, Y.;Kayama, T. 1985: Production of high-yield pulp and its properties II. Morphological changes of TMP and alkaline sulfite CTMP during the refining stages. Mokuzai Gakkaishi 31: 20–27
Kollman, F. F. P.;Coté, W. A. 1968: Principles of wood science and technology. Vol. 1 Solid wood. p 311. Springer-Verlag Berlin, Heidelberg, New York
Koran, Z. 1967: Electron microscopy of radial tracheid surfaces of black spruce separated by tensile failure at various temperatures. Tappi 50: 60–67
Koran, Z. 1968: Electron microscopy of tangential tracheid surfaces of black spruce produced by tensile failure at various temperatures. Svensk Papperstidn. 71: 567–576
Koran, Z. 1970: Surface structure of thermomechanical pulp fibers studied by electron microscopy. Wood and Fiber 2: 247–258
Koran, Z. 1979: Tensile properties of spruce under different conditions. Wood and Fiber. 11: 38–49
Koran, Z. 1984: Wood failure under torsional loading as a function of temperature. Wood Fiber Sci. 16: 12–19
Koran, Z.;Salmén, L. 1985: Shear strength analysis of spruce in a controlled environment. Svensk Papperstidn. 89: R90-R95
Peng, F.;Simonson, R.;Westermark, U. 1992: Cell wall sulfur distribution in chemithermomechanical pulping of spruce. Nord. Pulp Pap. Res. J. 6: 140–143
Salmén, N. L.;Fellers, C. 1982: The fundamentals of energy consumption during viscoelastic and plastic deformation of wood. Pulp Pap. Mag. Can. Trans. Tech. Sec. 83: TR93-TR99
Westermark, U.;Samuelsson, B.;Simonson, R.;Pihl, R. 1987: Investigation of a selective sulfonation of wood chips. Part 5. Thermomechanical pulping with low addition of sulfite. Nord. Pulp Paper Res. J. 2: 146–151
Westermark, U.;Samuelsson, B. 1993: A spectrophotometric method for the determination of sulfonic acids in wood material. Nordic Pulp Pap. Res. J. 8: 358–359, 398
Woodward, C. 1980: Fractured surfaces as indicators of cell wall behavior at elevated temperatures. Wood Science. 13: 83–86
Author information
Authors and Affiliations
Additional information
Financial support from the Swedish National Board for Industrial and Technical Development (NUTEK) is gratefully acknowledged
Rights and permissions
About this article
Cite this article
Johansson, L., Peng, F. & Simonson, R. Effects of temperature and sulfonation on shear deformation of spruce wood. Wood Sci.Technol. 31, 105–117 (1997). https://doi.org/10.1007/BF00705926
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00705926