セルロースおよびリグニン溶剤を用いた木材のセット

抄録

Wood was plasticized with several solvents for cellulose and lignin, i. e. dimethylsulphoxide (DMSO), and DMSO solutions of SO₂ (SO₂-DMSO), of SO₂-diethylamine complex (SO₂-DEA-DMSO), and of N₂O₄ (N₂O₄-DMSO), and the plasticized wood specimens were set under a constant deformation condition by displacing the solvents with water followed by drying. The residual stress in the plasticized wood specimens under torsional deformation and the elastic modulus of torsion were measured during the displacement and drying process. Furthermore, the residual deformation in bending after successive steps of the process and the springback of the set specimens in water were determined.
The most effective setting was obtained by the treatment with N₂O₄-DMSO. A highly effective setting, compared with the drying-set of untreated wood, was also obtained by the treatment with other solvents. The viscosity measurement of cellulose and lignin solutions in these solvents and X-ray study of the treated wood suggest that the decrystallization of wood with N₂O₄-DMSO and the swelling of lignin in wood with the solvents promote the flow of the network constituting wood substances and that the successive rearrangement of the network during the removal of solvents with water and subsequent drying fixes the deformation of the specimens.