The deformation fixation of the compressive Populus ussuriensis and Larix gmelinii solid wood was studied in this paper. Dynamic thermo-mechanical analyzer was used to evaluate the change of the treated wood on differ...The deformation fixation of the compressive Populus ussuriensis and Larix gmelinii solid wood was studied in this paper. Dynamic thermo-mechanical analyzer was used to evaluate the change of the treated wood on different position (compare with the non-compressive control wood). The internal mechanism of compressive solid wood and compressive deformation fixation were discussed by analyzing the effect of steam treatment on dynamic thermo-mechanical parameters of the treated wood, such as loss modulus and loss tangent. The tendency of the wood components such as hemi-cellulose and lignin were also studied in this course. The results showed that with the increasing of surface distance, loss modulus and loss angle tangent decreased in glass state area, the initial glass transition temperature decreased obviously at 0.5 cm away from the surface. So the deformation fixation of the compressive wood is due to the lower molecule weight of lignin and the failure of creep recovery.展开更多
Poplar lumber (Populus ussuriensis) is impregnated with low molecular weight PF resin, then it is heated and compressed so that the resin is fixed in wood. The wood is called surface compressive wood. This paper measu...Poplar lumber (Populus ussuriensis) is impregnated with low molecular weight PF resin, then it is heated and compressed so that the resin is fixed in wood. The wood is called surface compressive wood. This paper measured the index of physical mechanical properties. The result show that the average density of untreated wood is 415kg·m -3 , with the increase of compression set, the density went up clearly. From surface to inner the density is decrease gradually. With the increase of compression set , the compression strength of parallel to grain, bending strength, modulus of elasticity and surface hardness is raised obviously. The color of wood is slightly varied to yellow.展开更多
文摘The deformation fixation of the compressive Populus ussuriensis and Larix gmelinii solid wood was studied in this paper. Dynamic thermo-mechanical analyzer was used to evaluate the change of the treated wood on different position (compare with the non-compressive control wood). The internal mechanism of compressive solid wood and compressive deformation fixation were discussed by analyzing the effect of steam treatment on dynamic thermo-mechanical parameters of the treated wood, such as loss modulus and loss tangent. The tendency of the wood components such as hemi-cellulose and lignin were also studied in this course. The results showed that with the increasing of surface distance, loss modulus and loss angle tangent decreased in glass state area, the initial glass transition temperature decreased obviously at 0.5 cm away from the surface. So the deformation fixation of the compressive wood is due to the lower molecule weight of lignin and the failure of creep recovery.
文摘Poplar lumber (Populus ussuriensis) is impregnated with low molecular weight PF resin, then it is heated and compressed so that the resin is fixed in wood. The wood is called surface compressive wood. This paper measured the index of physical mechanical properties. The result show that the average density of untreated wood is 415kg·m -3 , with the increase of compression set, the density went up clearly. From surface to inner the density is decrease gradually. With the increase of compression set , the compression strength of parallel to grain, bending strength, modulus of elasticity and surface hardness is raised obviously. The color of wood is slightly varied to yellow.
