Effects of Wood Preservatives on Physical Properties of Wood II. Effects of Different Salt Loadings of Copper-Chrome-Arsenic Composition

Authors

  • Satish Kumar
  • V. K. Jain

Keywords:

<i>Pinus roxburghii</i>, <i>Mangifera indica</i>, salt retention, hygroscopicity, equilibrium moisture content, dimensional stability, shrinkage, swelling, preservation, copper-chrome-arsenic preservatives

Abstract

Effect of different salt loadings of copper-chrome-arsenic (CCA) preservative on shrinkage, swelling, and equilibrium moisture content at various relative humidities has been reported for Pinus roxburghii and Mangifera indica. At very low salt retentions, treated wood shows excessive shrinkage and swelling, which reaches a maximum and then falls off with increasing salt loadings. The two woods differ as to the position of these maxima. At higher retention levels, shrinkage and swelling are reduced, but the wood becomes more hygroscopic. The increased hygroscopicity is probably due to CCA salt and the additional water is held by the salt molecules deposited in the cell lumens. At low salt retentions, equilibrium moisture content is lowered at all relative humidities. The general sigmoid character of the adsorption curves is maintained at all levels of retentions.

References

Bavendamm, W., H. Willeitner, and M. Kruznev. 1963. Practical investigations on the formation of drying checks on impregnated timber. Part 1: The effect of preservatives on check formation, Holz Roh-Werkst. 21:369-79.nBendtsen, B. A. 1966. Sorption and swelling characteristics of salt-treated wood. USDA For. Serv. Res. Paper FPL-60.nBurmester, A. 1970. Long-term effect of wood preservatives on physical and mechanical wood properties. Environment Canada Trans. No. 00 ENV TR 91, from Holz Roh-Werkst. 28:478-485.nChristensen, G. N., and K. E. Kelsey. 1958. The sorption of water vapor by the constituents of wood. Determination of sorption isotherms. Aust. J. Appl. Sci. 9(3):265-282.nChudnoff, M. 1955. The effect of zinc chloride on some shrinkage properties of Eucalyptus rostrata wood. For. Prod. J. 5(2): 139-41.nDickinson, D. J. 1974. The micro-distribution of copper-chrome-arsenate in Acer pseudo-platanus and Eucalyptus maculata. Mater. Organ. 9(1):21-33.nGilfedder, J. J., W. G. Keating, and I. Robertson. 1968. Influence of certain preservatives on pole splitting. For. Prod. J. 18(1):28-30.nGreaves, H. 1974. Electron probe X-ray analysis of selected anatomical structures in copper-chrome-arsenic treated wood. Wood Sci. 7(2):164-168.nKamesam, S. 1933. Indian Patent No. 19859. (British Patent No. 404, 855, 1934)nKauman, W. G. 1960. Collapse in some eucalyptus after treatment in inorganic salt solutions. For. Prod. J. 10(9):463-467.nKeating, W. G., and J. J. Gilfedder. 1965. Distribution of moisture in treated and untreated poles. For. Prod. J. 15(6):251.nKumar, S., and V. K. Jain. 1976. The effect of wood preservatives on physical properties of wood. (1) Effect of copper-chrome-arsenic and acid-copper-chrome compositions on shrinkage-swelling behavior of wood. Holzforsch. Holzverwertung 28(2):37-40.nMackay, J. F. G. 1973. Surface checking and drying behavior of Pinus radiata sapwood boards treated with CCA preservatives. For. Prod. J. 23(9):92-97.nNicholas, D. D. 1972. Characteristics of preservative solutions which influence their penetration into wood. For. Prod. J. 22(5):31-36.nPetty, J. A., and R. D. Preston. 1968. Electron probe microanalysis of metals in cell walls of conifer wood treated with preservatives. Holzforschung 22(6):174-177.nRunkel, R. O. H., and M. Luthgens. 1956. Studies on sorption by wood fibres. 2. Investigations on the differences in water sorption of the chemical and morphological components of lignified cell walls. Holz Roh-Werkst. 14(11):424-441.nStamm, A. J. 1934. Effect of inorganic salts upon the swelling and the shrinking of wood. J. Amer. Chem. Soc. 56:1195-1204.nStamm, A. J. 1959. Dimensional stabilisation of wood by thermal reaction and formaldehyde cross linking. Tappi 42(1):38-44.nStamm, A. J. 1964. Wood and cellulose science. Ronald Press Co., N.Y.nStamm, A. J. 1974. Dimensional stabilization of wood with water soluble fire retardants. Bulking chemicals compared with polyethylene glycol-1000. Wood Sci. Tech. 8:300-306.nTarkow, H., A. J. Stamm, and E. C. O. Erickson. 1950. Acetylated wood. USDA For. Serv. Rep. 1593.n

Downloads

Published

2007-06-19

Issue

Section

Research Contributions