Induced Shrinkage and Structural Reorganisation in Ammonia-Treated Wood of Corsican Pine
Keywords:Pinus nigra var. calabrica, ammonia treatments, cell-wall crimping, internal swelling, collapse, plasticization, ray parenchyma, shrinkage, anatomy
AbstractThe ammonia-induced shrinkage of Corsican pine wood (Pinus nigra var. calabrica) was determined over a wide range of temperature, from the melting point (-78 C) to above the critical temperature (132 C) of liquid anhydrous ammonia. The swelling of wood was also measured but over a slightly more limited temperature range. The observed swelling and induced shrinkage of wood are explained in terms of two principal mechanisms: crimping and internal swelling of latewood and collapse of earlywood fibres. Confirmation of these mechanisms was provided by electron microscopy studies. Wood is most effectively plasticized between -5 and -33 C and this would seem to be the optimum temperature range for treating wood.
Bailey, N. T. J. 1959. Statistical methods in biology. English Universities Press.nBersinsh, G. V. 1971. U.S.S.R. studies compressed wood production. World Wood 12(2): 12-15.nBolton, A. J., P. Jardine, M. H. Vine, and J. C. F. Walker. 1974. The swelling of wood under mechanical restraint. Holzforschung 28(4): 138-145.nBrunauer, S., P. H. Emmett, and E. Teller. 1938. Adsorption of gases in multimolecular layers. J. Am. Chem. Soc. 60(2):309-319.nColes, R. W. 1973. Ultrastructural changes in ammonia-plasticized Corsican pine. Bull. Int. Assoc. Wood Anat. 1973(4):3-10.nColes, R. W. 1974. The effect of liquid ammonia on the density and structure of conifer wood. Ph.D. thesis, University of Wales. 151 pp.nDavidson, R. W. 1969. "Plasticising," a new process for wood bending. Furn. Meth. Mater. 15(2):26-29.nDinwoodie, J. M. 1968. Failure in timber, Part 1. Microscopic changes in cell-wall structures associated with compression failure. J. Inst. Wood Sci. 4(3):37-53.nGoring, D. A. I. 1963. Thermal softening of lignin, hemicellulose, and cellulose. Pulp Paper Mag. Can. 64(12):T517-T527.nGreen, D., and C. Koch. 1971. Creep of wood after soaking in liquid ammonia. For. Prod. J. 21(11):50-51.nHess, K., and J. Gundermann. 1937. Concerning the influence of liquid ammonia on cellulose fibres (the formation of ammonia-cellulose I, ammonia-cellulose II and cellulose III). Chemische Berichte 70B: 1788-1799.nJolly, W. J., and C. J. Hallada. 1965. Liquid ammonia. Pages 1-45 in T. C. Waddington, ed. Non-aqueous solvent systems. Academic Press, London.nKerr, A. J., R. P. Kibblewhite, and I. A. Andrew. 1978. Effects of gaseous ammonia pulp-treatment variables on paper properties. Paper presented at 32nd APPITA General Conference. Sydney. April 1978.nKibblewhite, R. P., and A. J. Kerr. 1978. Fibre, wet web and paper properties of bisulphite pulps treated with gaseous ammonia. Paper presented at 32nd APPITA General Conference. Sydney. April 1978.nLewin, M., and L. G. Roldan. 1971. The effect of liquid anhydrous ammonia in the structure and morphology of cotton cellulose. J. Polym. Sci. 36C: 213-229.nO'Connor, J. J. 1972. Ammonia explosion pulping, a new fibre separation process. Tappi 55(3):353-358.nParham, R. A. 1971a. Crystallinity and ultrastructure of ammoniated wood. Part 1. X-ray crystallinity. Wood and Fiber 2(4):311-320.nParham, R. A. 1971b. Crystallinity and ultrastructure of ammoniated wood. Part 2. Ultrastructure. Wood and Fiber 3(1):22-34.nParham, R. A. R. W. Davidson, and C. H. de Zeeuw. 1972. Radial-tangential shrinkage of ammonia-treated loblolly pine wood. Wood Sci. 4(3): 129-136.nPentoney, R. E. 1966. Liquid ammonia-solvent combinations in wood plasticization. Properties of treated wood. Ind. Eng. Chem. Prod. Res. Develop. 5(2): 105-110.nPimental, G. C., and A. L. Mcclellan. 1960. The hydrogen bond. W. H. Freeman & Co.nPollisco, F. S., C. Skaar, and R. W. Davidson. 1971. Some physical properties of maple wood treated with ammonia vapor. Wood Sci. 4(2):65-70.nSchuerch, C. 1964. Wood plasticization. For. Prod. J. 14(9):377-381.nSchuerch, C., and R. W. Davidson. 1971. Status of ammonia-treated wood and wood products. 7th Cellulose Conference. S.U.N.Y. Col. of Envir. Sci. and For. Syracuse. NY 13210.nSkaar, C. 1972. Water in wood. Syracuse University Press, Syracuse.nStamm, A. J., and H. Tarkow. 1950. Penetration of cellulose fibres. J. Phys. Colloid Chem. 54(6):745-753.nStamm, A. J., and H. Tarkow. 1955. Swelling of wood and fiberboards in liquid ammonia. For. Prod. J. 5(6):413-416.nStamm, A. J., and H. Tarkow. 1964. Wood and cellulose science. Ronald Press Co., New York.nYan, M. M., and C. B. Purves. 1956. Attempted delignifications with sodium bicarbonate, carbon dioxide, and with anhydrous liquid ammonia under pressure. Can. J. Chem. 34(2): 1582-1590.n
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