Evaluation of Cellulose Nanofi bers by Using Sedimentation Method

Abstract

The practicality of sedimentation method for evaluating the diameter and morphology of cellulose nanofi ? bers （CNFs） in CNF dispersions was studied using CNFs with diff erent degrees of fi brillation prepared by the mechanical fi brillation of softwood bleached kraft pulp. Evaluations of the CNF dispersions were per? formed using a stability analyzer and centrifuge particle size analyzer based on the gravitational sedimenta? tion method and diff erential centrifugal sedimentation （DCS） method, respectively. The sedimentation behav? ior of CNFs provided by the stability analyzer refl ected the fi ber morphologies, and good correlation was found between the Stokes’ diameter obtained by the DCS method and the fi ber diameters estimated from fi eld–emission scanning electron microscopy observations. These results show the possibility of using analysis based on the sedimentation method for evaluating the diameter and morphology of cellulose fi bers in CNF dispersions, including the cellulose fi bers obtained by fi brillation.