Dislocations in Norway spruce fibres and their effect on properties of pulp and paper
-
Nasko Terziev
Abstract
Wood “cell-wall deformation” is a comprehensive term describing any physical dislocation in the wall caused by mechanical forces. The development and effect of fibre dislocations on wood fibres, and their ultimate impact on the mechanical properties of paper remain rather obscure and controversial. Dislocations are difficult to quantify through a lack of defined measurable features, and research is aggravated by the inherent difficulties of applying statistical tools. A direct approach for studying the effect of dislocations on the mechanical properties of paper was used in this study. Dislocations in fibre cell walls were introduced by exposing whole wood fibres in mature and juvenile wood samples to compression stress. Sapwood samples of Norway spruce (Picea abies Karst.) were loaded by compression to their ultimate strength using an Alwetron-50 universal testing machine. Failure of samples conditioned to a moisture content of 9–15% always occurred in an oblique (relative to the fibre axis) plane and all fibres in the plane were deformed. When samples were loaded in a wet condition (i.e., moisture content close to the fibre saturation point), failure occurred at one end of the samples, resulting in highly disorganised fibres. Pulp and paper from the compressed fibres were produced and the mechanical properties of the paper were tested. Results of the mechanical tests were compared statistically to results derived from paper made from matched non-compressed control samples. Morphological features of fibres and dislocations after compression failure were characterised using microscopy (scanning electron microscopy, polarised light) on the whole wood and macerated fibres before and after paper testing. The above experimental approach showed that paper made from control samples had significantly better mechanical properties than paper made from samples loaded by compression under dry or wet conditions. At a tensile index of 90 N m/g, the tear index was measured as 23.6 mN m2/g for controls, while the corresponding values for compressed wet wood samples was 12.6 and 16.3 mN m2/g for samples at 9–15% moisture content. Paper made from juvenile wood also showed lower mechanical properties compared to controls. The results prove the negative effect of dislocations on the mechanical properties of paper in the worst case scenario and are of practical importance.
References
Dinwoodie, J.M. 1968. Failure in timber, Part I. Microscopic changes in cell wall structure associated with compression failure. J. Inst. Wood Sci.4, 35–37.Search in Google Scholar
Gindl, W. 2002. Comparing mechanical properties of normal and compression wood of Norway spruce: the role of lignin in compression parallel to the grain. Holzforschung56(4), 395–401.10.1515/HF.2002.062Search in Google Scholar
Hudson, W.M. 1961. The effect of pre-compression on the static and impact bending strength of wood. WoodJan. 1961, 18–20.Search in Google Scholar
Keith, C.T. 1971. The anatomy of compression failure in relation to creep-inducing stresses. Wood Sci.4(2), 71–82.Search in Google Scholar
Ito, Y., M. Tanahashi, M. Shigematsu and Y. Shinoda. 1998. Compressive molding of wood by high pressure steam treatment. Parts 1 and 2. Holzforschung52(2), 211–221.Search in Google Scholar
Kitahara, R., J. Tsutsumi and T. Matsumoto. 1984. Effect of static bending load on the mechanical behaviour of wood. J. Jpn. Wood Res. Soc.30(7), 522–529.Search in Google Scholar
Kucera, B. 1992. Scandinavian Standards for Testing of Small Wooden Specimens (in Norwegian). Norwegian Forest Research Institute.Search in Google Scholar
Monties, B. 2003. Biological variability of lignification and mechanical behaviour of woody plants. In: ESWM Conference, Stockholm, May 25–28. STFI. pp. 1–15.Search in Google Scholar
Navi, P. and F. Girardet. 2000. Effect of thermo-hydro-mechanical treatment on the surface and properties of wood. Holzforschung54(3), 287–293.Search in Google Scholar
Nyholm, K., A. Ander, S. Bardage and G. Daniel. 2001. Dislocations in pulp fibres – their origin, characteristics and importance – a review. Nord. Pulp Pap. Res. J.16(4), 376–384.Search in Google Scholar
Yang, J.L. 1998. An attempt to reduce collapse through introducing cell wall deformations. Wood Fibre Sci.30(1), 81–90.Search in Google Scholar
©2005 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Obituary
- The role of non-phenolic lignin in chlorate-forming reactions during chlorine dioxide bleaching of softwood kraft pulp
- Study of the oxygen effect on mechanical pulp lignin using an improved lignin isolation method
- Quantitative 1H NMR analysis of alkaline polysulfide solutions
- A comparative study on the degradation of cotton linters induced by carbonate and hydroxyl radicals generated from peroxynitrite
- The carbonate radical as one-electron oxidant of carbohydrates in alkaline media
- Leaf-fiber lignins of Phormium varieties compared bysolid-state 13C NMR spectroscopy
- Antifungal activity of iridoid glycosides from the heartwood of Gmelina arborea
- Antioxidant activity of different components of pine species
- Dislocations in Norway spruce fibres and their effect on properties of pulp and paper
- Isolation and identification of antifungal compounds from Amboyna wood
- Biomechanical pulping of spruce wood chips with Streptomyces cyaneus CECT 3335 and handsheet characterization
- Three-dimensional visualisation of bacterial decay in individual tracheids of Pinus sylvestris
- Mass loss and moisture dynamics of Scots pine (Pinus sylvestris L.) exposed outdoors above ground in Sweden
- The influence of cation and anion structure of new quaternary ammonium salts on adsorption and leaching
- Speciation of arsenic and chromium in the leachate from chromated copper arsenate (CCA) type C treated southern pine (Pinus spp.)
- Metal chelation studies relevant to wood preservation.1. Complexation of propyl gallate with Fe2+
- Comparison of UV and confocal Raman microscopy to measure the melamine–formaldehyde resin content within cell walls of impregnated spruce wood
- Comparison of Pinus taeda L. wood property calibrations based on NIR spectra from the radial-longitudinal and radial-transverse faces of wooden strips
- Detection of failures of adhesively bonded joints using the acoustic emission method
- Effect of cross-sectional change of a board specimen on stress wave velocity determination
- Comments on the experimental methodology for determination of the hygro-mechanical properties of wood
- Properties of chemically and mechanically isolated fibres of spruce (Picea abies [L.] Karst.). Part 1: Structural and chemical characterisation
- Properties of chemically and mechanically isolated fibres of spruce (Picea abies[L.] Karst.). Part 2: Twisting phenomena
Articles in the same Issue
- Obituary
- The role of non-phenolic lignin in chlorate-forming reactions during chlorine dioxide bleaching of softwood kraft pulp
- Study of the oxygen effect on mechanical pulp lignin using an improved lignin isolation method
- Quantitative 1H NMR analysis of alkaline polysulfide solutions
- A comparative study on the degradation of cotton linters induced by carbonate and hydroxyl radicals generated from peroxynitrite
- The carbonate radical as one-electron oxidant of carbohydrates in alkaline media
- Leaf-fiber lignins of Phormium varieties compared bysolid-state 13C NMR spectroscopy
- Antifungal activity of iridoid glycosides from the heartwood of Gmelina arborea
- Antioxidant activity of different components of pine species
- Dislocations in Norway spruce fibres and their effect on properties of pulp and paper
- Isolation and identification of antifungal compounds from Amboyna wood
- Biomechanical pulping of spruce wood chips with Streptomyces cyaneus CECT 3335 and handsheet characterization
- Three-dimensional visualisation of bacterial decay in individual tracheids of Pinus sylvestris
- Mass loss and moisture dynamics of Scots pine (Pinus sylvestris L.) exposed outdoors above ground in Sweden
- The influence of cation and anion structure of new quaternary ammonium salts on adsorption and leaching
- Speciation of arsenic and chromium in the leachate from chromated copper arsenate (CCA) type C treated southern pine (Pinus spp.)
- Metal chelation studies relevant to wood preservation.1. Complexation of propyl gallate with Fe2+
- Comparison of UV and confocal Raman microscopy to measure the melamine–formaldehyde resin content within cell walls of impregnated spruce wood
- Comparison of Pinus taeda L. wood property calibrations based on NIR spectra from the radial-longitudinal and radial-transverse faces of wooden strips
- Detection of failures of adhesively bonded joints using the acoustic emission method
- Effect of cross-sectional change of a board specimen on stress wave velocity determination
- Comments on the experimental methodology for determination of the hygro-mechanical properties of wood
- Properties of chemically and mechanically isolated fibres of spruce (Picea abies [L.] Karst.). Part 1: Structural and chemical characterisation
- Properties of chemically and mechanically isolated fibres of spruce (Picea abies[L.] Karst.). Part 2: Twisting phenomena
