Previous studies showed that the fiber morphology/structure can not only impact the hemicelluloses removal from pulp fibers (Li et al., 2015), but also affect the accessibility of cellulose to chemicals, such as carbon disulfide during the cellulose xanthation process (Tian et al., 2013), or enzymes during the cellulose enzy- matic viscosity control (Duan et al., 2015). Moreover, the fiber morphologies can be positively changed by the mechanical refining (Tian et al., 2014; Grönqvist et al., 2014).