화학공학소재연구정보센터
Journal of Materials Science, Vol.43, No.22, 7210-7218, 2008
Wet fiber shear flexibility and its contribution to the overall transverse deformation of fibers
A new method has been developed for measuring not only bending but also shear flexibility of pulp fibers by using confocal laser scanning microscopy. Based on the Steadman and Luner method, a two-stage wet pressing process was used which enabled both bending and shear flexibility and both bending and shear modulii of fibers to be determined with a single test. Three types of fibers, i.e., bleached spruce Kraft Pulp (BKP), aspen bleached chemi-themomechanical pulp (BCTMP), and aspen themomechanical pulp (CTMP), were tested. Results show that the longitudinal elastic modulii of the fibers are in a range of 3-37 GPa, and the transverse shear modulii of them are in a range of 27-103 MPa. It was also found that the shear contribution to the overall fiber deformation ranged from 60% to 90% for the fibers measured. This substantiates the concept of shear contribution to measured fiber flexibility as proposed by Waterhouse and Page.