A Percolation Model for Electrical Conduction in Wood with Implications for Wood-Water Relations
Keywords:
Ionic conduction, conductivity, percolation theory, wood—water relationsAbstract
The first models used to describe electrical conduction in cellulosic materials involved conduction pathways through free water. These models were abandoned in the middle of the 20th century. This article re-evaluates the theory of conduction in wood by using a percolation model that describes electrical conduction in terms of overlapping paths of loosely bound or capillary water (Type II water). The model contains two physical parameters: wc, the critical moisture fraction, which is the amount of water required to form a continuous path of Type II water in wood; and σc, the conductivity of the aqueous pathways. The model gives a good fit to previously published data of the DC conductivity of wood when wc is equal to 16% moisture content and σc is equal to 0.88 S m-1. This analysis indicates that electrical conduction in wood can be explained by percolation theory and that there exists a continuous path of Type II water in wood at wc, which is below the traditional fiber saturation point.References
Almeida G, Gagné S, Hernández R (2007) A NMR study of water distribution in hardwoods at several equilibrium moisture contents. Wood Sci Technol 41(4):293-307.nAnon (1999) 2520 Salinity in Standard methods for the examination of water and wastewater. American Public Health Association, Washington, DC. 8 pp.nBrown JH (1962) Some factors involved in the mechanism of electrical conduction in wood. PhD Dissertation. State University of New York College of Forestry at Syracuse. 139 pp.nBrunauer S, Emmett PH, Teller E (1938) Adsorption of gases in multimolecular layers. J Am Chem Soc 60(2): 309-319.nChristie JH, Sylvander SR, Woodhead IM, Irie K (2004) The electrical properties of humid cellulose. J Non-Cryst Solids 341(1-3):115-123.nClerc JP, Giraud G, Laugier JM, Luck JM (1990) The electrical conductivity of binary disordered systems, percolation clusters, fractals and related models. Adv Phys 39(3):191-309.nDennis JK, Zou C, Short NR (1995) Corrosion behaviour of zinc and zinc alloy coated steel in preservative treated timber. T I Met Finish 75(3):96-101.nDrude P (1900) Zur Elektronentheorie der Metalle. Ann Phys 306(3):566-613.nForest Products Laboratory (1999) Wood handbook: Wood as an engineering material. Gen Tech Rep FPL-GTR-113. USDA Forest Service, Forest Products Laboratory, Madison, WI. 463 pp.nGarboczi EJ, Snyder KA, Douglas JF (1995) Geometrical percolation threshold of overlapping ellipsoids. Phys Rev E 52(1):819-828.nHatakeyama H, Hatakeyama T (1998) Interaction between water and hydrophilic polymers. Thermochim Acta 308(1-2):3-22.nHearle JWS (1953) The electrical resistance of textile materials: IV. Theory. J Text I 44(7):T177-T198.nKärenlampi PP, Tynjälä P, Ström P (2005) Phase transformations of wood cell water. J Wood Sci 51(2):118-123.nKretschmann DE, Cramer SM (2007) The role of earlywood and latewood properties on dimensional stability of loblolly pine. The Compromised Wood Workshop. Christchurch, New Zealand. January 29-31, 2007. 24 pp.nKvålseth TO (1985) Cautionary note about R2. Am Stat 39:279-285.nLangwig JE, Meyer JA (1973) Ion migration in wood verified by neutron activation analysis. Wood Sci 6(1):39-50.nLin RT (1965) A study of electrical conduction in wood. PhD Dissertation. State University of New York College of Forestry at Syracuse. 196 pp.nLiu SH (1985) Fractal model for the AC response of a rough interface. Phys Rev Lett 55(5):529-532.nMacDonald JR, Johnson WB (1987) Fundamentals of impedance spectroscopy. Pages 1-26 in J R MacDonald, ed. Impedance spectroscopy emphasizing solid materials and systems. John Wiley & Sons, New York, NY.nMcLachlan DS, Chiteme C, Park C, Wise KE, Lowther SE, Lillehei PT, Siochi EJ, Harrison JS (2005) AC and DC percolative conductivity of single wall carbon nanotube polymer composites. J Polym SciPol Phys 43(22):3273-3287.nMcLachlan DS, Chiteme C, Park C, Wise KE, Lowther SE, Lillehei PT, Siochi EJ, Harrison JS, Heaney MB (1999) Complex AC conductivity of a carbon black composite as a function of frequency, composition, and temperature. Phys Rev B 60(18):12746-12751.nMcMillin CW (1970) Mineral content of loblolly pine wood as related to specific gravity, growth rate, and distance from pith. Holzforschung 24(5):152-157.nMurphy EJ, Walker AC (1928) Electrical conduction in textiles. I: The dependence of the resistivity of cotton, silk, and wool on relative humidity and moisture content. J Phys Chem 32(12):1761-1786.nNakamura K, Hatakeyama T, Hatakeyama H (1981) Studies on bound water of cellulose by differential scanning calorimetry. Textile Res J 51(9):607-613.nNan CW (1993) Physics of inhomogeneous inorganic materials. Prog Mater Sci 37(1):1-116.nO'Sullivan JB (1948) The conduction of electricity through cellulose. Part V. The effect of temperature. J Text I 39(11):T368-T384.nPark S, Venditti RA, Jameel H, Pawlak JJ (2006) Changes in pore size distribution during the drying of cellulose fibers as measured by differential scanning calorimetry. Carbohyd Polym 66(1):97-103.nRaistrick I D. (1987) The electrical analogs of physical and chemical processes. Pages 27-83 in JR MacDonald, ed. Impedance spectroscopy emphasizing solid materials and systems. John Wiley & Sons, New York, NY.nSimpson W (1980) Sorption theories applied to wood. Wood Fiber Sci 12(3):183-195.nSkaar C (1988) Wood-water relations. Springer-Verlag, New York, NY. 283 pp.nStamm AJ (1929) The fiber-saturation point of wood as obtained from electrical conductivity measurements. Ind Eng Chem Analyt Ed 1:94-97.nStamm A (1959) Bound-water diffusion into wood in the fiber direction. Forest Prod J 9(1):27-32.nStamm A (1964) Electrical properties. Pages 359-385 in A Stamm, ed. Wood and cellulose science. Ronald Press Company, New York, NY.nStauffer D, Aharony A (1992) Introduction to percolation theory. Taylor & Francis, London, UK. 181 pp.nTakahashi H, Mitomo H, Arai K, Takigami S (2003) Effect of cooling rate on freezing of wool—water mixtures. Textile Res J 73(7):597-605.nTomkiewicz M, Aurian-Blajeni B (1988) Impedance of composite materials. J Electrochem Soc 135(11):2743-2747.nVermaas HF (1974) A note on the mechanism of electrical conduction in wood. Holzforschung 28(4):145-148.nViitanen H (1996) Factors affecting the development of mould and brown rot decay in wooden material and wooden structures—Effect of humidity, temperature and exposure time. Swedish University of Agricultural Sciences, Department of Forest Products, Uppsala, Sweden. 58 pp.nViitanen H, Ojanen T (2007) Improved model to predict mold growth in building materials. Pages 1-8 in Proc Thermal Performance of the Exterior Envelopes of Whole Buildings X. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.nYing L, Kretschmann DE, Bendtsen BA (1994) Longitudinal shrinkage in fast-grown loblolly pine plantation wood. Forest Prod J 44(1):58-62.nZelinka SL, Rammer DR, Stone DS Impedance spectroscopy and circuit modeling of southern pine above 20% moisture content. Holzforschung (submitted).nZelinka SL, Rammer DR, Stone DS, Rammer DR (2007) Equivalent circuit modeling of wood at 12% moisture content. Wood Fiber Sci 39(4):556-565.n
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
