Artificial weathering of tropical woods. Part 1: Changes in wettability
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Abstract
Changes in the wettability of eight species of tropical woods during artificial weathering up to 600 h are discussed from the aspect of chemical and structural changes in their surfaces: Amnurana acreana, Acacia auriculiformis, Dipterocarpus spp., Eucalyptus marginata, Eucalyptus robusta, Shorea spp., and Tabebuia spp. with relatively high and low specific gravity. On the whole, the wettability of specimens decreased upon irradiation up to 20 h; above that they increased. Changes in wettability during artificial weathering differed according to wood species. The IR spectra suggest that the specimen surfaces after irradiation for 600 h result in a cellulose-rich layer, and therefore the increase in wettability during artificial weathering can be explained in terms of the increase in hydroxyl groups originating from both the exposed cellulose and adsorbed water. However, the difference in wettability exists between species even after the surface develops a cellulose-rich layer. The stereoscopic micrographs showed the development of cracks for all of the specimens after irradiation for 600 h, and differences in their magnitudes according to species. From these results, the differences in wettability between species were estimated to be due to the structural changes on the surface during artificial weathering, whereas the increase in wettability was due to the chemical changes.
References
Bouchard, J., Douek, M. (1993) Structural and concentration effects on the diffuse reflectance FTIR spectra of cellulose, lignin and pulp. J. Wood Chem. Technol.13(4):481–499.10.1080/02773819308020530Search in Google Scholar
Evans, P.D. (1989) Structural changes in Pinus radiata during weathering. J. Inst. Wood Sci.11(5):172–181.Search in Google Scholar
Feist, W.C., Hon, D.N.-S. (1984) Chemistry of weathering and protection. In: The Chemistry of Solid Wood. Ed. Rowell, R.M. Advances in Chemistry Series, No. 207. American Chemical Society, Washington, DC. Chapter 11, pp. 401–451.10.1021/ba-1984-0207.ch011Search in Google Scholar
Hon, D.N.-S. (1991) Photochemistry of wood. In: Wood and Cellulosic Chemistry. Eds. Hon, D.N.-S., Shiraishi, N. Marcel Dekker, New York. pp. 525–555.Search in Google Scholar
Hon, D.N.-S., Minemura, S. (1991) Color and discoloration. In: Wood and Cellulosic Chemistry. Eds. Hon, D.N.-S., Shiraishi, N. Marcel Dekker, New York. pp. 395–454.Search in Google Scholar
Kalnins, M.A., Feist, W.C. (1993) Increase in wettability with weathering. Forest Prod. J.43(2):55–57.Search in Google Scholar
Patton, T.C. (1970) A simplified review of adhesion theory based on surface energetics. Tappi53(3):421–429.Search in Google Scholar
Tolvaj, L., Faix, O. (1995) Artificial ageing of wood monitored by DRIFT spectroscopy and CIE L*a*b* color measurements. Holzforschung, 49:397–404.10.1515/hfsg.1995.49.5.397Search in Google Scholar
Williams, R.S., Knaebe, M.T., Sotos, P.G., Feist, W.C. (2001a) Erosion rates of wood during natural weathering. Part I. Effects of grain angle and surface texture. Wood Fiber Sci.33(1):31–42.Search in Google Scholar
Williams, R.S., Knaebe, M.T., Sotos, P.G., Feist, W.C. (2001b) Erosion rates of wood during natural weathering. Part II. Earlywood and latewood erosion rate. Wood Fiber Sci.33(1):43–49.Search in Google Scholar
Williams, R.S., Knaebe, M.T., Sotos, P.G., Feist, W.C. (2001c) Erosion rates of wood during natural weathering. Part III. Effect of exposure angle on erosion rate. Wood Fiber Sci.33(1):50–57.Search in Google Scholar
© Walter de Gruyter
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Articles in the same Issue
- The effects of initial spacing on wood density, fibre and pulp properties in jack pine (Pinus banksiana Lamb.)
- An improved procedure for isolation of residual lignins from hardwood kraft pulps
- Small angle scattering in the Porod region from hydrated paper sheets at varying humidities
- Application of confocal Raman spectroscopy for the topochemical distribution of lignin and cellulose in plant cell walls of beech wood (Fagus sylvatica L.) compared to UV microspectrophotometry
- UV-microscopic analysis of acetylated spruce and birch cell walls
- On-line study of lignin behaviour in dilute alkaline solution by the SEC-UV method
- Extracellular diffusion pathway for heartwood substances in Albizia julibrissin Durazz.
- New glucosides from Eucalyptus globulus wood, bark and kraft pulps
- Nondestructive characterization of wood by monitoring of local elastic anisotropy and dynamic nonlinearity
- Chemical reaction of maritime pine sapwood (Pinus pinaster Soland) with alkoxysilane molecules: A study of chemical pathways
- Thermal forming of chemically modified wood to make high-performance plastic-like wood composites
- Eco-composite from poly(lactic acid) and bamboo fiber
- Bamboo fiber (BF)-filled poly(butylenes succinate) bio-composite – Effect of BF-e-MA on the properties and crystallization kinetics
- Dimensional changes in Corsican pine (Pinus nigra Arnold) modified with acetic anhydride measured using a helium pycnometer
- Microwave-enhanced release of formaldehyde from plywood
- Artificial weathering of tropical woods. Part 1: Changes in wettability
- Artificial weathering of tropical woods. Part 2: Color change
- Inhibition of fungal degradation of wood by 2-hydroxypyridine-N-oxide
- Microwave treatment to accelerate fixation of copper-ethanolamine (Cu-EA) treated wood
